EP2517084A1

EP2517084A1 - Signal-level selection for electrical signal transmission between electronic devices

Info

Publication number: EP2517084A1
Application number: EP10735281A
Authority: EP
Inventors: Michael Bahr; Andrzej Trebisz
Original assignee: Cinterion Wireless Modules GmbH
Current assignee: Telit Cinterion Deutschland GmbH
Priority date: 2009-12-23
Filing date: 2010-07-21
Publication date: 2012-10-31
Also published as: WO2011076449A1

Abstract

The invention relates to an electronic signal-transmitting device, an electronic signal-processing device, an assembly of an electronic signal-transmitting device and an electronic signal-processing device, and methods of operating them. The fist electronic device provides different trial output voltages to the electronic signal-processing device. The electronic signal-processing device selects a voltage from a set comprising at least one of the trial output voltages provided by the electronic signal-transmitting device, and outputs it to the electronic signal-transmitting device as a reference voltage for a signal generation unit in the electronic signal-transmitting device, which generates signals such that the signal level of the signals is determined by the reference voltage. The generated signals are provided to the electronic signal-processing device. By selecting an appropriate one of the trial output voltages provided by the electronic signal-transmitting device, the electronic signal-processing device has the possibility to select the signal level of the signals itself. This allows for a simple and reliable adjustment of the signal level for different electronic signal-processing devices without delay and without need for external components.

Description

Signal-Level Selection for Electrical Signal Transmission Between Electronic Devices

The invention is concerned with means and methods for improved electrical signal transmission between electronic devices. Different aspects of the invention relate to an electronic signal- transmitting device, an electronic signal-processing device, an assembly comprising an electronic signal-transmitting device and an electronic signal-processing device, a method for operating an electronic signal-transmitting device, a method for operating an electronic signal-processing device and a method for operating an assembly comprising an electronic signal-transmitting device and an electronic signal-processing device. Care has to be taken that a signal exchange between electrically coupled electronic devices meets specific signal-amplitude (hereinafter: signal-level) requirements of the electronic signal-processing device. Typically, the electronic signal-processing device requires that an information or control signal received from the connected electronic signal-transmitting device has a certain signal level, which can, for example, be above a specific signal-level threshold, such as a voltage amount in an on-state or a maximum voltage level of an analogue signal.

A method for adjusting a signal level for communication between two electronic devices is known from US 2009/0271678 A1. The method includes the detection of the correct signal level, for example by transferring data with a certain signal level and detecting whether an error occurred in the transfer of data or not. Such methods need a certain amount of time before it is ensured that the correct signal level is used in the electrical signal exchange.

An alternative arrangement is known from US 5,541 ,534. This document describes a voltage converter receiving a signal from a signal-transmitting electronic device formed by circuitry implemented with a first CMOS technology. The signal has a first voltage level that is not acceptable for input into a signal-processing device formed by circuitry implemented with a second CMOS technology, which instead requires an input with a second voltage level for correct operation. The signal is converted from the first to the second voltage level and then transmitted to the circuitry implemented with the second CMOS technology.

It would be desirable to achieve the correct signal level in the electrical signal exchange between an electronic signal-transmitting device and an electronic signal-processing device fast and with reduced complexity.

A first aspect of the present invention is formed by a method for operating an assembly of an electronic signal-transmitting device and an electronic signal-processing device according to claim 17.

A second aspect of the present invention is formed by a method for operating an electronic signal-transmitting device according to claim 1 1.

A third aspect of the present invention is formed by a method for operating an electronic signal- processing device according to claim 13.

A fourth aspect of the present invention is formed by an electronic signal-transmitting device according to claim 1.

A fifth aspect of the present invention is formed by an electronic signal-processing device according to claim 5.

A sixth aspect of the present invention is formed by an assembly according to claim 16 comprising an electronic signal-transmitting device according to the fourth aspect and an electronic signal-processing device according to the fifth aspect.

A seventh aspect of the present invention is formed by an electronic device according to claim 10. Electronic devices according to the present invention each comprise an electrical interface unit by means of which they can be connected for signal exchange with another (also referred to as "external") electronic device and exchange user data, control data or both using electrical information or control signals. In a signal exchange between two such electronic devices under consideration, one electronic device forms an electronic signal-transmitting device and another device forms an electronic signal-processing device, which receives and typically processes the information and/or control signals received from the electronic signal-transmitting device. In the context of the present specification, merely forwarding a signal is considered an embodiment of signal processing. The electronic signal-transmitting device may for instance be an RF (radio frequency) communication module which has the capability to exchange electromagnetic signals with other devices over a wireless communication channel, e.g., a terrestrial wireless access network, according to for instance a GSM, UMTS, LTE, Bluetooth, WLAN, Zigbee or another known RF communication standard. However, it is mentioned for the sake of clarity that in the context of the present speci- fication RF communication using electromagnetic signals transmitted via an air interface is not considered as the electrical signal exchange or signal transmission.

The electronic signal-processing device is preferably an application device. For instance, the signal-processing device may serve to control the operation of a machine. If the electronic signal-transmitting device is an RF communication module, RF communication of the electronic signal-processing device with one or more external application devices is enabled. Examples of application devices are vending machines, teller machines, security systems, mobiles, laptops, telematic boxes, navigation systems, tracking systems or cameras. An example for an external application device in the mentioned context is a central control entity that is configured to allow a remote control and monitoring of application devices from another location. It should be noted that such external application devices may also form application devices in the sense of the present context and may contain an RF communication module.

As an assembly under operation, the two electronic devices perform the method according to the first aspect of the present invention.

According to the first aspect of the invention, a method for operating an assembly of an elec- tronic signal-transmitting device and an electronic signal-processing device, which are coupled via respective interface units, comprises:

providing at least two different trial output voltages in parallel from the electronic signal- transmitting device to the electronic signal-processing device; selecting, at the signal-processing device, from a set of voltages comprising at least one of the trial output voltages received from the electronic signal-transmitting device, one voltage as a reference voltage;

providing the reference voltage from the electronic signal-processing device to the elec- tronic signal-transmitting device;

providing, at the electronic signal-transmitting device, the received reference voltage to a signal generation unit of the electronic signal-transmitting device;

generating, at the electronic signal-transmitting device, at least one information or control signal;

- providing the at least one information or control signal from the electronic signal- transmitting device to the electronic signal-processing device with a signal level that is determined by the reference voltage.

The method according to the first aspect of the invention provides for an easy and reliable way of selecting a signal level of an information or control signal, which is to be delivered from the electronic signal-transmitting device to the electronic signal-processing device, on the side of the electronic signal-processing device itself.

As the electronic signal-processing device can plainly feed a selected one of the trial output voltages, that are provided by the electronic signal-transmitting device, back to the electronic signal-transmitting device, where it is used to generate the information or control signal, the correct signal level of the information or control signal can be achieved on the side of the electronic signal-transmitting device without delay and without need for external components. In particular, the method of the first aspect of the invention avoids voltage conversion and corresponding circuitry and thus reduces the circuit complexity required in the prior art for providing voltage conversion functionality. According to an embodiment, a step of receiving, at a voltage input port of the second interface unit, at least a selected one of the at least two trial output voltages provided by the electronic signal-transmitting device is performed, wherein the electronic signal-processing device selects the selected one of the trial output voltages from the trial output voltages received from the electronic signal-transmitting device. In this embodiment, the selected trial output voltage is output at the second interface unit as a reference voltage to the electronic signal-transmitting device.

Further advantages and embodiments of the method of the first aspect of the invention will be explained further below in the context of other method aspects of the invention, which are represented by a method for operating an electronic signal-transmitting device and by a method for operating an electronic signal-processing device. Thus, according to a second aspect of the invention, a method for operating an electronic signal-transmitting device comprises the steps of:

providing at least two different trial output voltages in parallel to an electronic signal- processing device, which is external to the electronic signal-transmitting device;

- receiving a reference voltage from the external electronic signal-processing device;

providing the received reference voltage to a signal generation unit of the electronic signal-transmitting device;

generating at least one information or control signal in the signal generation unit; and providing the at least one information or control signal to the external electronic signal- processing device with a signal level that is determined by the received reference voltage.

The method according to the second aspect of the invention represents the process of operation of the electronic signal-transmitting device in performing the method of the first aspect of the invention.

By means of this method, the electronic signal-transmitting device provides an external electronic signal-processing device with the possibility of applying a voltage selection between the at least two different trial output voltages. However, an alternative voltage, that can be generated or received by the electronic signal-processing device, can also be received by the electronic signal-transmitting device, if none of the trial voltages provided by the electronic signal- transmitting device is found to be suitable.

The voltage selection or provision by the external electronic signal-processing device serves to define the voltage that in further operation will allow the electronic signal-transmitting device to generate signals with a signal level adapted for the signal-level requirements of the external electronic signal-processing device.

Thus, the method according to the second aspect of the invention contributes, on the side of the electronic signal-transmitting device, to an easy and reliable way of ensuring that information or control signals, when provided to any external electronic signal-processing device making use of the present invention, have the correct signal level according to the specific input requirements of this electronic signal-processing device. Merely by receiving back the selected trial output voltage as a reference voltage from the external electronic signal-processing device, or by receiving an alternative voltage, the method allows ensuring that the signal generation unit of the electronic signal-transmitting device generates an information or control signal with the signal level needed by the external electronic signal-processing device.

It should be noted that the term "external" is used in this specification to indicate that the electronic signal-processing device and the electronic signal-transmitting device are different entities. When considering the electronic signal-transmitting device, the electronic signal-processing device is external. When considering the electronic signal-processing device, the electronic signal-transmitting device is external. In particular, the electronic signal-transmitting device and the electronic signal-processing device are typically not integrated in the form of integrated circuitry on a single chip. Typically, the electronic signal-transmitting device and the electronic signal-processing device are fabricated independently from each other, often even by different manufacturers, and often on different printed circuit boards. A connection between the electronic signal-transmitting device and the external electronic signal-processing device for signal exchange as discussed herein can be established after the fabrication processes by suitably coupling the interface units of the devices. However, it is also possible that the electronic signal- transmitting device and the electronic signal-processing device are integrated in a single chip or on a common printed circuit.

The term "trial output voltage" in the context of this application denotes those voltages that are provided from a signal-transmitting device to a signal-processing device in order to give the latter a possibility to select one of these voltages that best suits its signal-level requirements. The term is not to be understood in a sense that the voltages are intended for a trial operation producing any unknown result. An alternative term that could be used in the context of the present application instead of "trial output voltage", but with the same described meaning, is "supply voltage".

In the following, embodiments of the method of the second aspect of the invention will be described. It should be noted that these embodiments at the same time form embodiments of the method of the first aspect of the invention. There are a number of variants of the method that allow adapting the provision of the trial output voltages to the needs of a particular application context of the electronic signal-transmitting device.

According to one embodiment, the trial output voltages are provided by a trial-voltage supply unit comprised by the electronic signal-transmitting device. In an alternative embodiment, the trial output voltages are provided to the electronic signal-transmitting device from an external voltage supply device.

The trial output voltages may be derived from one of various sources known in the art. For instance, the trial output voltages may be provided using a power management ASIC (application specific integrated circuit).

According to a preferred embodiment, the electronic signal-transmitting device, for its operation, receives electric power from an external power source. The electric power for operation should not be confused with the reference voltage received from the external electronic signal- processing device. The electric power is provided independently from the reference voltage. The reference voltage received through the interface unit is fed solely to the signal generation unit, while the electric power serves to energize the electronic signal-transmitting device for operation.

According to another embodiment, the trial output voltages are generated by the electronic signal-transmitting device independently from the reference voltage received back from the external electronic signal-processing device, i.e., the reference voltage is not used as a base voltage or reference for generating the trial output voltages. This embodiment has the advantage that the voltage that is received from the external electronic signal-processing device is only used as the reference voltage of the signal generation unit, avoiding any change of the reference voltage by electrically interfering with other components like the trial-voltage supply unit that could result in unwanted changes of the information or control signal.

As mentioned, the signal level provided by the electronic signal-transmitting device at the interface unit is determined by the reference voltage. Different electronic signal-processing devices may require different signal levels. To provide a suitably large selection of trial output voltages, at least two, but preferably three different trial output voltages are provided in parallel from the electronic signal-transmitting device to the external electronic signal-processing device. An even larger number of parallel trial output voltages to select from may be used and allows achieving signal-level compatibility with an even larger number of electronic signal-processing devices.

Suitably, the different trial output voltages have voltage amounts within a specified range of allowable voltages of the signal generation unit of the electronic signal-transmitting device. This way, malfunction or even damage of the signal generation unit is prevented. In one embodiment, the different trial output voltages all amount to less than 5 V, thus forming CMOS- compatible voltages. As mentioned, the voltage received by the electronic signal-transmitting device as the reference voltage is in one embodiment provided to the signal generation unit only, i.e., to no functional unit of the electronic signal-transmitting device other than the signal generation unit. The reference voltage can this way be provided without being disturbed by any other entity inside the electronic signal-transmitting device.

The signal level can be defined as a maximum signal level of a signal, being the maximum amount of a physical quantity, such as a voltage amount, that a signal assumes in the course of time. The signal level of the information or control signal generated by the signal generation unit preferably equals the received reference voltage. However, in an alternative embodiment, the signal level of the information or control signal is reduced, for instance by a resistor, in comparison with the received reference voltage. Alternatively, the signal level of the information or control signal is increased over the received reference voltage, for instance by a converter.

According to an embodiment, at least one of the two different trial output voltages is received back from the external electronic signal-processing device. The received trial output voltage is provided as a reference voltage to the internal signal generation unit of the electronic signal- transmitting device.

According to a third aspect of the invention, a method for operating an electronic signal- processing device comprises:

selecting, from a set of voltages comprising at least one trial output voltage received from an electronic signal-transmitting device that is external to the electronic signal-processing device, one voltage as a reference voltage;

outputting the reference voltage to the external electronic signal-transmitting device; receiving at least one information or control signal from the electronic signal-transmitting device, the information or control signal having a signal level that is determined by the selected reference voltage; and

processing the at least one information or control signal.

The method according to the third aspect of the invention is connected to the methods of the other aspects of the invention in that it comprises the steps of the method of the first aspect of the invention performed by the electronic signal-processing device in connection with an electronic signal-transmitting device that performs the method of the second aspect of the invention.

The method of the third aspect of the invention ensures that the electronic signal-transmitting device generates the information or control signal with a signal level that meets the signal-level requirements of the electronic signal-processing device. The method lets the electronic signal- processing device set a suitable signal level of the information or control signal according to its own requirements by selecting from a set of voltages, comprising at least one trial output voltage received from the electronic signal-transmitting device. It is thus ensured that the correct signal level of the information or control signal is applied without delay.

In the following, embodiments of the method of the third aspect of the invention will be described. As before, the additional features of the embodiments may be combined with each other to form further embodiments, unless such additional features mutually exclude each other and form alternative embodiments. The method according to the third aspect of the invention is preferably applied in an electronic signal-processing device that is coupled to and exchanges signals with an electronic signal- transmitting device that performs the method of the second aspect of the invention, when the electronic signal-processing device and the electronic signal-transmitting device should communicate with each other.

In an embodiment, a step of receiving at least a selected one of at least two trial output voltages provided by the external electronic signal-transmitting device, which is coupled to the electronic signal-processing device, at a voltage input port is performed. The selected trial output voltage is output as the reference voltage to the electronic signal-transmitting device.

The electronic signal-processing device can suitably select from the trial output voltages received from the electronic signal-transmitting device according to a signal-level requirement of a signal processing unit of the electronic signal-processing device. If none of the trial output voltages is found suitable, the set of voltages may comprise an alternative voltage different from the trial output voltages provided by the electronic signal-transmitting device.

The signal processing unit, in further operation of the electronic signal-processing device, receives information or control signals from the electronic signal-transmitting device with a signal level that is determined by this selection step. Accordingly, there is no delay time in the adjustment of the signal level, and the further operation of the arrangement of the electronic signal-transmitting device and the electronic signal-processing device is not disturbed by signal- level problems in the mutual signal exchange.

According to an embodiment, the set of voltages comprises at least one trial output voltage different from the trial output voltages provided by the electronic signal-transmitting device. The provision of such an alternative voltage can be implemented either by receiving the alternative voltage from some entity external to the electronic signal-processing device, or by generating the alternative voltage inside the electronic signal-processing device. It is even possible to use one of the trial output voltages received from the electronic signal-transmitting device as a reference to generate the alternative voltage.

Usually, the specifications of the electronic signal-transmitting device are known to a designer or manufacturer of an electronic signal-processing device. In such a situation, also the different trial output voltages provided by the electronic signal-transmitting device and, in particular, the trial output voltage of the electronic signal-transmitting device to be selected, if at least one is suitable, will be known in advance. In this situation, the electronic signal-processing device hardware may be designed such that it receives only the selected one of the at least two trial output voltages provided by the external electronic signal-transmitting device and does not receive the non-selected trial output voltages. This way, only the selected trial output voltage is indeed forwarded within the electronic signal-processing device, and the circuit complexity of the electronic signal-processing device may be kept low. The receiving step may for instance be implemented by physically blocking a reception of trial output voltages other than the selected one, e.g., by using a suitable voltage input port on the side of the electronic signal-processing device. The voltage input port may be physically arranged and/or configured such that it receives only the selected one of the trial output voltages provided by the electronic signal- transmitting device.

Non-selected trial output voltages provided by the electronic signal-transmitting device may alternatively be received, but then discarded by the electronic signal-processing device.

In another embodiment, the selection from the set of voltages, i.e. between the at least two trial output voltages receivable from the electronic signal-transmitting device and possibly the alternative voltage is performed by the electronic signal-processing device using a switch. With this embodiment, application modules can be adapted to interface configurations of different electronic signal-transmitting devices providing different sets of trial output voltages. The present embodiment is also useful where an electronic signal-processing device may be fabricated using signal processing units provided by different manufacturers, such as a main manufacturer and a backup manufacturer. Sometimes, such different signal processing units have mutually different signal-level requirements regarding the signal exchange with the electronic signal- transmitting device. A single PCB or casing ready to accommodate either one of the different signal processing units may include the switch. The switch can then simply be put into the right position during manufacture of the electronic signal-processing device in order to achieve the settings that best fit to the signal-level requirements of the respective chosen signal processing unit.

Instead of a switch, setting a jumper may also be used to select the required trial output voltage.

A switch in the electronic signal-processing device, that can be used to select between the different trial output voltages provided by the electronic signal-transmitting device and possibly an alternative voltage, can also be used to change the voltage level of the reference voltage during operation, e.g. when reduced power consumption is demanded.

Preferably, the trial output voltage that best satisfies a predetermined voltage requirement of the signal processing unit of the electronic signal-processing device regarding the signal level of information or control signals delivered to the signal processing unit is selected as the reference voltage. According to a preferred embodiment, the selected trial output voltage is only output as a reference voltage to the electronic signal-transmitting device, i.e., it is not used for any other purpose and not fed to another device unit. The selected trial output voltage is not disturbed or mod- ulated by any other entity inside the electronic signal-processing device.

It is noted that the electronic signal-processing device will typically receive power for operation at a power input port that is different from the voltage input port or ports of the electronic signal- processing device, through which the different trial output voltages are received from the elec- tronic signal-transmitting device.

According to a fourth aspect of the invention, an electronic signal-transmitting device is provided, the electronic signal-transmitting device comprising:

a trial-voltage supply unit, which is configured to provide at least two different trial output voltages in parallel;

a signal generation unit, which is configured to generate and provide at its output at least one information or control signal for delivery to an electronic signal-processing device, which is external to the electronic signal-transmitting device; and

an interface unit coupled to the trial-voltage supply unit and to the signal generation unit, the interface unit having ports that are connectable to the external electronic signal-processing device, and comprising

at least two trial-voltage output ports, each trial-voltage output port being connected with the trial-voltage supply unit to provide a respective one of the different trial- output voltages to the external electronic signal-processing device,

- a reference-voltage input port, which is configured to receive a reference voltage from the external signal-processing device and to provide the reference voltage to the signal generation unit, and

at least one signal output port, which is connected to the signal generation unit; wherein the signal generation unit is adapted to generate the at least one information or control signal with a signal level that is determined by the reference voltage.

The advantages of the electronic signal-transmitting device are clear from the above explanation of the advantages achieved by the first to third aspects of the invention. In particular, the electronic signal-transmitting device according to the fourth aspect of the invention offers the possibility to select a suitable one of its trial output voltages for feedback to the reference- voltage input port of the electronic signal-transmitting device that causes the signal generation unit to generate the information or control signal according to the specific requirements of that electronic signal-processing device, without delay and without any need for additional equipment. In the following, embodiments of the electronic signal-transmitting device of the fourth aspect of the invention will be described. As before, the additional features of the embodiments may be combined with each other to form further embodiments, unless such additional features mutually exclude each other and form alternative embodiments.

To provide a suitably large selection of trial output voltages, three different trial output voltages are preferably provided in parallel from the electronic signal-transmitting device to the external electronic signal-processing device. An even larger number of parallel trial output voltages can be provided in order to achieve signal-level compatibility with a particularly large or heterogene- ous group of electronic signal-processing devices.

The interface unit can be implemented in different ways for providing a suitable connection of the electronic signal-transmitting device with the electronic signal-processing device. In one embodiment, the interface unit comprises a connector suitable for allowing a connection of the plug-and-socket type, mounted for instance on a printed circuit board. Alternatively, the interface unit comprises at least four pins or metallic stripes on a printed circuit board, which form the ports.

The interface unit should have at least four ports suitable for allowing a flow of electric current or an application of voltages between the electronic signal-transmitting device and the external electronic signal-processing device during operation.

Preferably, the electronic signal-transmitting device is configured to provide the different trial output voltages with voltage amounts within a specified range of voltages specified as allowable for forming the reference voltage of the signal generation unit. The external electronic signal- processing device can then choose a most suitable one of the trial output voltages for feedback to the electronic signal-transmitting device without risking damage or malfunction of the signal generation unit by application of unsuitable voltages. In one embodiment, the different trial output voltages are smaller than 5 V and thus CMOS-compatible.

The trial-voltage supply unit of the electronic signal-transmitting device can be implemented in different ways well known in the art in order to adapt it to different application contexts. According to one embodiment, the trial-voltage supply unit comprises two connectors adapted to receive two different voltages from some external entity outside the electronic signal- transmitting device. This way, no hardware for generating the trial output voltages is required inside the electronic signal-transmitting device.

Irrespective of its particular implementation, the trial-voltage supply unit is preferably configured to generate the different trial output voltages independently from the reference voltage received at the reference-voltage input port. In other words, the reference voltage is not used for generating the trial output voltages, for instance as a base voltage or reference, but is only used in the signal generation unit. Therefore, the at least one reference-voltage input port is preferably connected to forward the received reference voltage to the signal generation unit only.

The signal generation unit can be implemented in various ways in accordance with specific requirements. In general, the signal generation unit can be implemented in the form of any electronic component that is adapted to modulate a constant voltage, which the signal generation unit receives from the reference-voltage input port, to thus provide distinguishable signals representing user information (such as payload data) or control information (such as commands or control data).

In one embodiment, the signal generation unit comprises a microcontroller or an application specific integrated circuit (ASIC) being adapted to output a digital signal or an analogue signal, giving a high degree of flexibility in the generation of the information or control signal. However, the signal generation unit may also have a simple structure, comprising for instance a relais or a transistor, which can be used in order to either modulate on/off-signals (containing for example binary data), or an analogue signal as the information or control signal. The interface unit suitably comprises a number of signal output ports in addition to the trial-voltage output ports to output respective information or control signals delivered by the signal generation unit.

Typically, the electronic signal-transmitting device will comprise a power input that is connected with an external power source in order to receive electric power for its operation. The power input is preferably not, at least not directly connected with the trial-voltage output ports, the reference-voltage input port and the signal output port of the interface unit. Electric power for operation received at the power input will typically be used by the trial-voltage generation unit in order to generate the different trial output voltages. However, it should not be confused with the reference voltage received from the electronic signal-processing device, which is preferably fed solely to the signal generation unit.

It should be noted that the electronic signal-transmitting device can be designed to be connect- able with several electronic signal-processing devices. Typically, such an arrangement will comprise different signal generation units for the different electronic signal-processing devices which can be operated at different voltage levels. Either separate trial-voltage supply units can be present, or one trial-voltage supply unit is used to supply the trial output voltages for all electronic signal-processing devices.

According to a fifth aspect of the invention, an electronic signal-processing device is provided, the electronic signal-processing device comprising: an interface unit having ports that are connectable to an electronic signal-transmitting device that is external to the signal-processing device and that provides at least two trial output voltages in parallel;

voltage selection means connected to the interface unit and configured to select one voltage from a set of voltages comprising at least one of the trial output voltages and to feed the selected voltage as a reference voltage to a trial-voltage output port, which is connectable to the signal-transmitting device;

at least one signal input port, which is connectable to the signal-transmitting device and configured to receive an information or control signal;

- wherein a signal processing unit is connected to the signal input port and configured to process information or control signals having a signal level that is determined by the reference voltage selected by the voltage selection means.

The advantages of the electronic signal-processing device of the invention correspond to those explained above with respect to the other aspects of the invention. In particular, the electronic signal-processing device according to the fifth aspect of the invention allows selecting one of at least two trial output voltages, for instance provided by an external electronic signal-transmitting device according to the fourth aspect of the invention, and allows providing the selected trial output voltage back to the electronic signal-transmitting device. If none of the trial output voltag- es provided by the external electronic signal-transmitting device is found suitable, the set of voltages can also comprise at least one alternative voltage different from the trial output voltages of the external electronic signal-transmitting device, which can be delivered to the trial- voltage output port. This way, an adaptation of the electronic signal-transmitting device to the signal-level requirements of the individual signal-processing unit is enabled in a particularly simple manner.

In the following, different embodiments and variants of the electronic signal-processing device will be described. As before, the additional features of the embodiments may be combined with each other to form further embodiments, unless such additional features mutually exclude each other and form alternative embodiments.

The signal processing unit of the electronic signal-processing device will be adapted to specific application requirements. Depending on a given application context, a microcontroller, an application specific integrated circuit (ASIC), a relais, a transistor and other kinds of electronic circui- try are examples of devices forming the signal processing unit. However, the signal processing unit shall not be understood as necessarily being restricted to providing only an electrical output. Rather, power consuming devices like an electric motor or a light emitting device are also examples of a signal processing unit. The above examples show that basically any device that is responsive to an incoming signal may form the signal processing unit. An alternative voltage different from the trial output voltages provided by the electronic signal- transmitting device can be either generated inside the electronic signal-processing device or received by another port, which is not comprised by the interface unit. If the alternative voltage is selected to be output at the trial-voltage output port, the electronic signal-processing device can even be used if none of the trial output voltages provided by the fist electronic device is found suitable.

In an embodiment, the interface unit of the electronic signal-processing device comprises at least one voltage input port for receiving a selected one of the trial output voltages provided by the electronic signal-transmitting device and the at least one trial-voltage output port is configured to output the received trial output voltage.

If a trial output voltage provided by an electronic signal-transmitting device, connected with the electronic signal-processing device, should be provided to the trial-voltage output port, the interface unit of the electronic signal-processing device should have at least three ports, whereof one is a voltage input port receiving the trial output voltage. The ports can, for instance, have the form of suitable electrical connectors allowing a flow of electric current or the application of voltages between the electronic signal-transmitting device and the electronic signal- processing device. The interface unit is adapted such that it can be connected to an interface unit of the electronic signal-transmitting device.

The interface unit may for instance comprise a connector mounted on a printed circuit board. The voltage input ports of the electronic signal-processing device may be implemented by pins of a standard electrical connector that fits with a corresponding connector provided on the electronic signal-transmitting device. Alternatively, the interface unit comprises at least three pins or metallic stripes on a printed circuit board, which form the ports. In any of these cases, the interface unit typically comprises at least two voltage input ports for receiving trial output voltages from the signal-transmitting device, and the voltage selection means is configured to keep all of the ports for receiving trial output voltages inoperative except for the port which receives the voltage to be selected as the reference voltage. Being inoperative means being isolated from the circuitry of the electronic signal-processing device.

Suitably, the voltage selection means is configured to select from the set of voltages the voltage that best satisfies a predetermined voltage requirement of the signal processing unit regarding the maximum signal level of information or control signals delivered to the signal processing unit. Such signal-level requirements are typically known at the time of design or fabrication of the electronic signal-processing device. Thus, the electronic signal-processing device can be pre-configured during fabrication such that no further selection must take place after connecting to a suitable electronic signal-transmitting device. Compared with the prior art for adjusting the signal level, like using a microcontroller or voltage converters, there is no delay time in the adjustment of the signal level and there are no additional components needed. The voltage selection means suitably takes the form of a voltage selection unit which is configured to select one of the trial output voltages provided by the electronic signal-transmitting device or the alternative voltage for feedback to the electronic signal-transmitting device through the trial-voltage output port of the electronic signal-processing device. It may be implemented by active or passive circuit elements.

The non-selected trial output voltages provided by the electronic signal-transmitting device may be discarded already before entering the electronic signal-processing device, using passive circuit elements in the form of suitable electrical isolation means at the interface unit of the electronic signal-processing device. The voltage selection means is thus configured to block those trial output voltages offered by the electronic signal-transmitting device, which are not required by the electronic signal-processing device, from entering the electronic signal- processing device, using a suitable electrical isolation means well known in the art. This reduces the complexity and the number of components required inside the electronic signal- processing device.

In some embodiments, the voltage selection means either comprises or even consists of a fixed wiring connecting the voltage input port, at which the selected trial output voltage is received, and the trial-voltage output port. All other voltage input ports receiving non-selected trial output voltages of the electronic signal-transmitting device have suitable electrical isolation means that prevent an electrical feed-through for non-selected trial output voltages inside the electronic signal-processing device. This is a very simple and inexpensive form of implementing the voltage selection means.

As mentioned in the context of the corresponding method aspect, the voltage selection means may alternatively comprise a switch connected with at least two voltage input ports and with the trial-voltage output port, optionally also with means providing the alternative voltage, the switch being coupled to allow a switchable connection between a respective one of the voltage input ports and the trial-voltage output port. According to a preferred embodiment, the electronic signal-processing device comprises a power input that is configured for connection with an external power source for receiving electric power for operation of the electronic signal-processing device. The power input is preferably not connected with the voltage input ports or the trial-voltage output port. Thus, the electronic signal-processing device is provided with electric power in a manner that is totally independent from the trial output voltages of the electronic signal-transmitting device received at the voltage input ports.

According to a sixth aspect of the invention, an assembly of an electronic signal-transmitting device according to the fourth aspect and an electronic signal-processing device according to the fifth aspect is provided.

In the assembly according to the sixth aspect of the invention, the electronic signal-transmitting device can be implemented according to any of the embodiments according to the fourth aspect of the invention. Similarly, the electronic signal-processing device can be implemented according to any of the embodiments according to the fifth aspect of the invention. All variations and advantages discussed there also apply in the assembly according to the sixth aspect of the invention.

In some embodiments of the assembly, the electronic signal-transmitting and the electronic signal-processing device form separate, mutually connectable entities. Such separate devices may be fabricated by different manufacturers and subsequently be coupled in a process of system integration, for instance for the fabrication of a specific, more complex application device. The assembly may thus be implemented in the form of electrically connected separate modules, such as individual chips or printed circuit boards. However, another embodiment of the assembly takes the form of different circuit blocks of a monolithically integrated circuit, one circuit block forming the electronic signal-transmitting device an another circuit block forming the electronic signal-processing device.

A group of embodiments makes use of an ability of at least one of the electronic devices in an assembly according to the present invention to assume both roles, that of the signal-transmitting device and that of the signal-processing device. For instance, the electronic signal-transmitting device is in some embodiments additionally configured to perform a signal-processing function. It may even additionally form a signal-processing device according to the present invention. Vice versa, the electronic signal-processing device is in some embodiments additionally configured to perform a signal-transmitting function. It may even additionally form an electronic signal- transmitting device according to the present invention.

In one such embodiment from this group, the electronic signal-transmitting device is configured to assume the additional function of a signal-processing device according to the present invention in a signal exchange with an additional third electronic device, to which it is connectable. In this kind of arrangement, the third electronic device thus is a further signal-transmitting device according to the present invention. Further electronic devices may be integrated in the same manner, forming further pairs of electronic signal-transmitting and signal-processing devices, respectively.

According to a seventh aspect of the invention there is provided an electronic device, comprising:

- a trial-voltage supply unit, which is configured to provide at least two different trial output voltages in parallel;

a signal generation unit, which is configured to generate and provide at its output at least one information or control signal;

a first interface unit coupled to the trial-voltage supply unit and to the signal generation unit, the first interface unit having ports that are at least partially connected to respective ports of a second interface unit, and comprising

at least two trial-voltage output ports, each trial-voltage output port being connected with the trial-voltage supply unit and being configured to provide a respective one of the different trial output voltages,

- a reference-voltage input port, which is configured to receive a reference voltage and to provide the reference voltage to the signal generation unit, and

at least one signal output port, which is connected to the signal generation unit; voltage selection means configured to select one voltage from a set of voltages comprising at least one of the trial output voltages and to feed the selected voltage as a reference voltage to a trial-voltage output port of the second interface unit, which is connected to the reference-voltage input port of the first interface unit;

the second interface unit further comprising at least one signal input port, which is connected to the signal output port of the first interface unit and configured to receive an information or control signal;

- wherein the signal generation unit is adapted to generate the at least one information or control signal with a signal level that is determined by the reference voltage,

and wherein a signal processing unit is connected to the signal input port and configured to process information or control signals having a signal level that is determined by the reference voltage selected by the voltage selection means. The electronic device according to the seventh aspect is especially preferable if features of the electronic signal-transmitting device according to the fourth aspect and features of the electronic signal-processing device according to the fifth aspect are to be combined with a high degree of integration, e.g. on one single integrated circuit. An electronic device according to the seventh aspect can even be fabricated e.g. by using one single mask set in which features of both the electronic signal-transmitting device according to the fourth aspect and features of the electronic signal-processing device according to the fifth aspect are implemented. However, it should be noted that the present invention is not limited to specific functions or realizations of the electronic signal-transmitting and signal-processing devices. In this application, the electronic signal-transmitting device represents an entity sending information to an electronic signal-processing device, representing an information receiving electronic entity, notwithstanding that the electronic signal-processing device could also send information to the electronic signal-transmitting device. Additionally, the electronic signal-transmitting device can be connected with several electronic signal-processing devices, and the electronic signal- processing device can be connected with several electronic signal-transmitting devices.

Further embodiments are defined by the enclosed dependent claims.

These and other aspects of the invention will be apparent from the embodiments described herein after with reference to the drawings, in which:

Figs. 1A to 1 C show block diagrams of an assembly 10 comprising an electronic signal- transmitting device 20 and an electronic signal-processing device 30 in three different configurations,

Fig. 2 shows an embodiment of an assembly according to the sixth aspect of the invention, incorporating an electronic signal-transmitting device according to the fourth aspect and an electronic signal-processing device according to the fifth aspect of the invention,

Fig. 3 shows a preferred version of the embodiment shown in Fig. 2, with a very simple implementation of the voltage selection means,

Fig. 4 shows a flow diagram of an embodiment of the method for operating an electronic signal- transmitting device according to the second aspect of the invention, and

Fig. 5 shows a flow diagram of an embodiment of the method for operating an electronic signal- processing device according to the third aspect of the invention.

Fig. 1A shows a simplified block diagram of an assembly 10 comprising an electronic signal- transmitting device 20 and an electronic signal-processing device 30 in a first configuration.

The following specification describes the signal transmission between two electronic devices according to the invention in an assembly as an exemplary embodiment of the present invention. However, it should be kept in mind that an assembly according to the present invention may comprise more than two electronic devices. In such an assembly, comprising for instance three electronic devices, a third electronic device may in different embodiments assume the role of either the electronic signal-transmitting or the electronic signal-processing device with respect to signal exchange with any one of the other electronic devices. In other words, the present invention does not require an assembly to comprise only one of the first and electronic signal- processing devices, respectively. The electronic signal-transmitting device 20 is intended for allowing a remote control of the electronic signal-processing device 30 via an air interface (not shown). To this end, the electronic signal-transmitting device 20 is adapted to transmit a plurality of information and/or control signals Si to S_n to the electronic signal-processing device 30. The information or control signals must match signal-level requirements of the electronic signal-processing device. Different electronic signal-processing devices have different signal-level requirements. Therefore, usage of the correct signal level of the information and/or control signals for the specific electronic signal-processing device 30 has to be ensured.

The electronic signal-transmitting device 20 is adapted to provide three different trial output voltages V-i , V₂ and V₃, at trial-voltage output ports 40.1 , 40.2 and 40.3 to respective voltage input ports 45.1 , 45.2 and 45.3 of the electronic signal-processing device 30. In other embodiments, another number of trial output voltages can be provided by the electronic signal- transmitting device 20. Of course, the number of trial output voltages must be larger than two to allow a selection of a suitable trial output voltage by the electronic signal-processing device.

In the present implementation, the trial output voltages have amounts of V-i = 1 ,6 V, V₂ = 1 ,8 V and V₃ = 2,85 V.

In the first configuration shown in Fig. 1A, the electronic signal-processing device 30 has an internal electrical connection 60 that couples only the voltage input port 45.1 , and not the other voltage input ports 45.2 and 45.3, with a trial-voltage output port 85 of the electronic signal- processing device 30. The trial-voltage output port 85 is connected with a reference-voltage input port 80 of the electronic signal-transmitting device 20. This way, the trial output voltage V-i of the electronic signal-transmitting device 20 is provided back to the electronic signal- transmitting device 20.

In the present embodiment, the electrical connection 60 is implemented by a fixed conductive path. In other embodiments, the electrical connection 60 is implemented by a switchable connection that allows a switching of the conduction path to connect the trial-voltage output port 85 with a selected one of the voltage input ports 45.1 to 45.3. The switching may be performed by a control unit (not shown in Fig. 1 A) within the electronic signal-processing device 30. The trial output voltage V-i that is provided back to the electronic signal-transmitting device from the electronic signal-processing device 30 at the reference-voltage input port 80 is used inside the electronic signal-transmitting device 20 to generate a plurality of information or control signals Si to S_n. The signal level of the information or control signals Si to S_n is determined by the amount of the trial output voltage V-| . In particular, the signal level of the present embodiment in the present first configuration equals the amount of the trial output voltage V-| .

The information or control signals Si to S_n are provided to the electronic signal-processing device 30 via respective signal output ports 90.1 to 90. n of the electronic signal-transmitting device, which are connected with respective signal input ports 95.1 to 95. n of the electronic signal-processing device 30.

Fig. 1 B shows the embodiment of Fig. 1A, in a second configuration. The following description focuses on the differences between the two configurations. All structural elements shown in Fig. 1 B are identical to those shown in Fig. 1A, and the same reference labels are used for that reason. The second configuration differs from the first configuration in the electrical connection 60 in the electronic signal-processing device 30, which is a fixed conductive path. Instead of providing only the trial output voltage V-i in the first configuration, in the second configuration the conductive path provides only the trial output voltage V₂ back to the electronic signal- transmitting device 20. As explained before, V₂ is provided by the electronic signal-transmitting device 20 in parallel with the trial output voltages V-i and V₃.

Accordingly, the information or control signals Si to S_n are generated by the electronic signal- transmitting device 20 using the trial output voltage V₂, leading to a signal level of the informa- tion or control signals Si to S_n determined by V₂, and, in the present embodiment, equal to V₂. In the present example, the trial output voltage V₂ is higher than the trial output voltage V-i , such that the signal level of the information or control signals Si to S_n is higher in the embodiment of Fig. 1 B compared with the embodiment of Fig. 1A. Fig. 1 C shows the arrangement of Fig. 1A in a third configuration, which differs from the foregoing in that only the trial output voltage V₃ is provided back to the electronic signal-transmitting device 20, and not the voltages V-i and V₂.

As described with reference to Figs. 1A, 1 B and 1 C, the shown arrangement is configurable to assume one of three different signal levels of the information or control signals Si to S_n by an appropriate configuration of the electrical connection 60, i.e., by selecting a specific one of the trial output voltages V-i , V₂ or V₃. For each of the three configurations, a respective diagram in Figs. 1A, 1 B and 1 C, illustrates as an example a signal voltage V of an information or control signal versus time t of a square- shaped signal. The signals must match threshold limits. The selection of the suitable one of the trial output voltages V-i , V₂ or V₃ can be accomplished inside the electronic signal-processing device 30.

Different electronic signal-processing devices needing different signal levels of the information or control signals Si to S_n can be configured to select a respective suitable trial output voltage V-i , V₂ or V₃ of the electronic signal-transmitting device 20 in order to adapt the signal level of the information or control signals Si to S_n. Thus, the arrangement of Figs. 1A to 1 C shows that the present invention provides a possibility to use an electronic signal-transmitting device with different electronic signal-processing devices needing different signal levels without any need for microcontrollers or external components, like voltage converters, in order to ensure that the correct signal level of the information or control signals Si to S_n is applied, and without any delay in the application of the correct signal level.

Fig. 2 shows, by way of a block diagram, an assembly 100 of an electronic signal-transmitting device 200 and an electronic signal-processing device 400, in accordance with the sixth aspect of the invention mentioned earlier.

The electronic signal-transmitting device 200 comprises a trial-voltage supply unit 220, a power input 240, a signal generation unit 260 and an interface unit 300. The interface unit 300 of the electronic signal-transmitting device 200 comprises three trial- voltage output ports 310, 320 and 330 connected with the trial-voltage supply unit 220, one reference-voltage input port 340 connected with the signal generation unit 260, and three signal output ports 350, 360 and 370, which are also connected with the signal generation unit 260. The power input 240 is connected with the trial-voltage supply unit 220.

The electronic signal-processing device 400 comprises a voltage selection unit 420, an alternative voltage input port 425, a signal processing unit 440, a power input 460 and an interface unit 500. The interface unit 500 of the electronic signal-processing device 400 comprises three voltage input ports 510, 520 and 530 connected with the voltage selection unit 420, a trial-voltage output port 540, which is also connected with the voltage selection unit 420, and three signal input ports 550, 560 and 570, which are connected with the signal processing unit 440. The power input 460 is connected with the signal processing unit 440. The alternative voltage input port 425 is connected with the voltage selection unit 420.

Respective ports of the interface unit 300 of the electronic signal-transmitting device 200 on one side and of the interface unit 500 of the electronic signal-processing device 400 are suitably connected with each other, as explained in the following. The trial-voltage output ports 310, 320 and 330 of the electronic signal-transmitting device 200 are connected with the voltage input ports 510, 520 and 530 of the electronic signal-processing device 400. The reference-voltage input port 340 of the electronic signal-transmitting device 200 is connected with the trial-voltage output port 540 of the electronic signal-processing device 400, and the signal output ports 350, 360 and 370 of the electronic signal-transmitting device 200 are connected with the signal input ports 550, 560 and 570 of the electronic signal-processing device 400.

The trial-voltage supply unit 220 and the signal generation unit 260 can be implemented as separate electronic circuits of the electronic signal-transmitting device 200 on a common printed circuit board (PCB). Preferably, however, they are implemented together in a single integrated circuit. It is important that the two units are electrically separated from each other. That means that the units are arranged such that electrical interference between them is prevented. The same is true for the voltage selection unit 420 and the signal processing unit 440 of the electronic signal-processing device 400.

In the present embodiment, the trial-voltage supply unit 220 provides three different trial output voltages V-i , V₂ and V₃, in parallel to the respective trial-voltage output ports 310, 320 and 330 of the interface unit 300. To this end, the trial-voltage supply unit 220 can comprise three DC-DC- converters which perform a respective voltage conversion of a base voltage.

The power input 240 is connected with an external power source (not shown) supplying electric power for operation of the trial-voltage supply unit 220. Additionally, the power input 240 can be used to provide other components (not shown) of the electronic signal-transmitting device with electric power for operation.

Turning to the electronic signal-processing device, in operation the voltage input ports 510, 520 and 530 of the interface unit 500 of the electronic signal-processing device 400 receive the trial output voltages V-i , V₂ and V₃ from the trial-voltage output ports 310, 320 and 330 of the electronic signal-transmitting device in parallel. The voltage input ports 510, 520 and 530 are connected with the voltage selection unit 420 of the electronic signal-processing device 400. The voltage selection unit 420 operates to put out only one of the three different trial output voltages V-i , V₂ and V₃ received from the electronic signal-transmitting device to the trial-voltage output port 540 of the interface unit 500 of the electronic signal-processing device 400. In the present embodiment, pins on a printed circuit board are provided that can be connected by a jumper in order to select which one of the three trial output voltages V-i , V₂ and V₃ is provided to the trial- voltage output port 540. However, if none of the three different trial output voltages V-i , V₂ and V₃ are found to be suitable, the voltage selection unit 420 can put an alternative voltage received at the alternative voltage input port 425 to the trial-voltage output port 540. In a modification of the shown embodiment, it is even possible to omit the voltage input ports 510, 520 and 530, if it is not intended at all to use one of the three trial output voltages V-i , V₂ and V₃. Turning back to the operation of the electronic signal-transmitting device, the selected one of the trial output voltages V-i , V₂ and V₃, or the alternative voltage, that is received at the reference-voltage input port 340 of the electronic signal-transmitting device 200 from the trial-voltage output port 540 of the electronic signal-processing device 400, is delivered to the signal generation unit 260 as a reference voltage. The signal generation unit 260 modulates the reference voltage such that information or control signals S-i , S₂ and S₃ are generated, which have a signal level that corresponds to the voltage, which has been selected as the reference voltage.

It should be noted that the number of ports providing information and control signals, which are generated by the signal generation unit of the electronic signal-transmitting device using the selected reference voltage, may of course differ from the number of trial output voltages offered to the electronic signal-processing device for selection. The numbers of trial output voltages and information or control signals in the present embodiment are of exemplary nature. In the present embodiment, the signal generation unit is implemented using transistors in order to generate a signal by modulation of the reference voltage. The information or control signals S-i , S₂ and S₃ can be any kind of electric signals, e. g. binary data signals, non-return-to-zero-signals (NRZ signals), analogue signals, amplitude-modulated signals, frequency-modulated signals, phase- modulated signals, or the like.

The three information or control signals S-i , S₂ and S₃ are provided to respective signal output ports 350, 360 and 370 of the interface unit 300 of the electronic signal-transmitting device 200. Of course, if a different number of information or control signals are used, the number of signal output ports may differ accordingly.

The information or control signals S-i , S₂ and S₃ are received at the respective signal input ports 550, 560 and 570 of the electronic signal-processing device 400 and are fed to the signal processing unit 440, which performs application-specific tasks in response to the incoming information or control signals. In the present embodiment, the signal processing unit is implemented by a microcontroller or microprocessor, which interprets and processes the information or control signals.

Note that the power input 460 of the electronic signal-processing device 400 is connected with an external power source. The external power source may at the same time be used as a power supply also for the electronic signal-transmitting device.

However, the signal processing unit 440 may in other embodiments be implemented by circuit elements which are driven directly by the information or control signals S-i , S₂ and S₃. In such embodiments, a power supply to the signal processing unit may not be required.

Thus, different electronic signal-processing devices 400 are enabled to select a respective suitable signal level of the information or control signals S-i , S₂ and S₃ simply by selecting the appropriate trial output voltage V-i , V₂ or V₃ or by providing a suitable alternative voltage. The electronic signal-transmitting device is provided with flexibility for usage with different types of electronic signal-processing devices, while it is at the same time ensured that the correct signal levels of information or control signals are applied from the beginning of operation and without delay and any need for components like voltage converters on the side of the electronic signal- processing device.

Fig. 3 shows a an embodiment of the invention, which differs from Fig. 2 only in that the voltage selection unit 420 is implemented by a fixed conductive path 430 between the voltage input port 520 and the trial-voltage output port 540. The conductive path may comprise a via provided between different metallization levels of a printed circuit board. This allows for a very simple and reliable selection of the trial output voltage (in this example V₂), which is to be selected as the reference voltage for the signal generation unit 260. The other two voltage input ports 510 and 530 are electrically isolated and thus not used in operation. This way, the trial output voltages V-i and V₃, which are provided by the electronic signal-transmitting device, are discarded. Variations and advantages mentioned in the context of the embodiment shown in Fig. 2 of course apply also to the present embodiment of Fig. 3.

Fig. 4 shows a flow diagram of an embodiment of a method for operating an electronic signal- transmitting device, in accordance with the second aspect of the invention. The shown embodi- ment does not use any alternative voltage in addition to the trial output voltages provided by the electronic signal-transmitting device.

In a step S41 , an electronic signal-transmitting device provides different trial output voltages in parallel to an external electronic signal-processing device. At least two different trial output voltages are to be provided in order to allow a selection of one of the provided trial output voltages. For example, if the method is performed by the electronic signal-transmitting device shown in Fig. 2, three trial output voltages are provided to the external electronic signal- processing device in step S41.

In a step S42, the selected one of the different trial output voltages is received back from the external electronic signal-processing device. Thus, when this step is performed by the electronic signal-transmitting device, the electronic signal-processing device has already selected a specific one from the at least two different trial output voltages provided to the external electronic signal-processing device in step S41 .

In a step S43, the trial output voltage received back in step S42 is provided to an internal signal generation unit as a reference voltage. In a step S44, information or control signals are generated in the signal generation unit, using for instance transistors in the present embodiment, such that a signal level of the information or control signals is determined by the reference voltage that has been provided in step S43. Three information or control signals are generated if the method is applied by an electronic signal-transmitting device as shown in the embodiment of Fig. 2.

In a step S45, the information or control signals generated in step S44 are output to the external electronic signal-processing device.

When the method of Fig. 4 is applied, an external electronic signal-processing device can adjust the signal level of the information or control signals simply by selecting a specific one of the different trial output voltages that are provided in step S41 , and feeding it back to the electronic signal-transmitting device for reception in step S42. This allows for an easy and reliable adjustment of the information or control signals that are provided to the electronic signal-processing device in step S45 by the electronic signal-processing device itself, according to its own re- quirements. There is no delay and no need for external components.

Fig. 5 shows a flow diagram of a method for operation of an electronic signal-processing device, in accordance with the third aspect of the invention. The shown embodiment does not use any alternative voltage in addition to the trial output voltages provided by the electronic signal- transmitting device.

In a step S51 , a selected one of trial output voltages provided by an external electronic signal- transmitting device is received at a voltage input port. In a step S52, the selected one of the trial output voltages is output as a reference voltage to the electronic signal-transmitting device.

In a step S53, information or control signals are received from the electronic signal-transmitting device, which have a signal level that is determined by the reference voltage provided to the electronic signal-transmitting device. If the method is applied by an electronic signal-processing device according to the embodiment shown in Fig. 2, three information or control signals are received from the electronic signal-transmitting device. The method of Fig. 5 lets the electronic signal-processing device itself select the signal level of the information or control signals received in step S53 by selecting one of the trial output voltages provided by the electronic signal-transmitting device. This is especially advantageous if the method is used in an electronic signal-processing device that is connected with an electronic signal-transmitting device operated according to the method shown in Fig. 4. The correct signal level of the information or control signals received in step S53 can be adjusted by different electronic signal-processing devices having different signal-level requirements without delay and without need for external components.

The following is a juxtaposition of terms used in this specification and corresponding terms of the earlier application EP 09 180 690.1 The correspondence between the terms in one line of the table implies that the meaning of the terms of the earlier application EP 09 180 690.1 is either identical to that used in the present specification or is comprised by the meaning of the corresponding term of the present specification in an embodiment.

This specification Specification of EP 09 180 690.1

Electronic signal-transmitting device RF communication module

Trial-voltage supply unit Voltage supply unit

Electronic signal-processing device Application device

Reference voltage Supply voltage

Trial output voltage, supply voltage output voltage

Reference-voltage input port Voltage input port

Trial-voltage output port Voltage output port List of reference labels

10 Assembly

20 Electronic signal-transmitting device 30 Electronic signal-processing device

Si tO S_n Information and/or control signals

VL V₂, V₃ Trial output voltages

40.1 , 40.2, 40.3 Trial-voltage output ports

45.1 , 45.2, 45.3 Voltage input ports

60 Internal electrical connection

80 Reference-voltage input port

85 Trial-voltage output port

90.1 to 90.n Signal output ports

100 Assembly

200 Electronic signal-transmitting device

220 Trial-voltage supply unit

240 Power input

260 Signal generation unit

300 Interface unit

310, 320, 330 Trial-voltage output ports

340 Reference-voltage input port

350, 360, 370 Signal output ports

400 Electronic signal-processing device

420 Voltage selection unit

425 Alternative voltage input port

430 Conductive path

440 Signal processing unit

460 Power input

500 Interface unit

510, 520, 530 Voltage input ports

540 Trial-voltage output port

550, 560, 570 Signal input ports

S41 , S42, S43, S44, S45, S51 , S52, S53 Steps

Claims

1. An electronic signal-transmitting device (20, 200), comprising:

a trial-voltage supply unit (220), which is configured to provide at least two different trial output voltages in parallel;

a signal generation unit (260), which is configured to generate and provide at its output at least one information or control signal for delivery to an electronic signal-processing device (30, 400), which is external to the electronic signal-transmitting device (20, 200); and

an interface unit (300) coupled to the trial-voltage supply unit (220) and to the signal generation unit (260), the interface unit having ports (40.1 , 40.2, 40.3, 80, 90.1 , 90. n, 310, 320, 330, 340, 350, 360, 370) that are connectable to the external electronic signal-processing device (30, 400), and comprising

- at least two trial-voltage output ports (40.1 , 40.2, 40.3, 310, 320, 330), each trial- voltage output port being connected with the trial-voltage supply unit (220) to provide a respective one of the different trial output voltages to the external electronic signal- processing device (30, 400),

a reference-voltage input port (80, 340), which is configured to receive a reference voltage from the external signal-processing device (30, 400) and to provide the reference voltage to the signal generation unit (260), and

at least one signal output port (90.1 , 90. n, 350, 360, 370), which is connected to the signal generation unit (260);

wherein the signal generation unit (260) is adapted to generate the at least one informa- tion or control signal with a signal level that is determined by the reference voltage.

2. The electronic signal-transmitting device (20, 200) according to claim 1 , wherein the trial- voltage supply unit (220) is configured to generate the trial output voltages independently from the received reference voltage.

3. The electronic signal-transmitting device (20, 200) according to one of the preceding claims, wherein the at least one reference-voltage input port (80, 340) is connected to forward the received reference voltage to the signal generation unit (260) only.

4. The electronic signal-transmitting device (20, 200) according to one of the preceding claims, wherein the different trial output voltages are within a range of voltages specified as allowable for forming the reference voltage to the signal generation unit (260).

5. An electronic signal-processing device (30, 400) comprising:

an interface unit (500) having ports (45.1 , 45.2, 45.3, 85, 95.1 , 95.n, 510, 520, 530, 540, 550, 560, 570) that are connectable to an electronic signal-transmitting device (20, 200) that is external to the signal-processing device (30, 400) and that provides at least two trial output voltages in parallel;

voltage selection means (60, 420, 430) connected to the interface unit (500) and configured to select one voltage from a set of voltages comprising at least one of the trial output voltages and to feed the selected voltage as a reference voltage to a trial-voltage output port (85, 540), which is connectable to the signal-transmitting device (20, 200);

- at least one signal input port (90.1 , 90. n, 550, 560, 570), which is connectable to the signal-transmitting device (20, 200) and configured to receive an information or control signal; wherein a signal processing unit (440) is connected to the signal input port (90.1 , 90. n, 550, 560, 570) and configured to process information or control signals having a signal level that is determined by the reference voltage selected by the voltage selection means (420).

6. The electronic signal-processing device (30, 400) according to claim 5, wherein the set of voltages comprises at least one voltage different from the trial output voltages provided by the electronic signal-transmitting device (20, 200).

7. The electronic signal-processing device (30, 400) according to claim 5 or 6, wherein the voltage selection means is configured to select from the set of voltages the voltage that best satisfies a predetermined voltage requirement of the signal processing unit (440) regarding the signal level of information or control signals delivered to the signal processing unit (440).

8. The electronic signal-processing device (30, 400) according to one of the claims 5 to 7, wherein the interface unit (500) comprises at least two ports (45.1 , 45.2, 45.3, 510, 520, 530) for receiving trial output voltages from the signal-transmitting device (20, 200), and wherein the voltage selection means (60, 420, 430) is configured to keep all of the ports (45.1 , 45.2, 45.3, 510, 520, 530) for receiving trial output voltages inoperative except for the port, which receives the voltage to be selected as the reference voltage.

9. The electronic signal-processing device (30, 400) according to one of the claims 5 to 7, wherein the voltage selection means (60, 420, 430) is configured to discard all trial output voltages received by the interface unit (500) except for the selected voltage.

10. An electronic device, comprising:

a trial-voltage supply unit (220), which is configured to provide at least two different trial output voltages in parallel; a signal generation unit (260), which is configured to generate and provide at its output at least one information or control signal;

a first interface unit (300) coupled to the trial-voltage supply unit (220) and to the signal generation unit (260), the first interface unit having ports (40.1 , 40.2, 40.3, 80, 90.1 , 90. n, 310, 320, 330, 340, 350, 360, 370) that are at least partially connected to respective ports (45.1 , 45.2, 45.3, 85, 95.1 , 95.n, 510, 520, 530, 540, 550, 560, 570) of a second interface unit (500), and comprising

at least two trial-voltage output ports (40.1 , 40.2, 40.3, 310, 320, 330), each trial- voltage output port being connected with the trial-voltage supply unit (220) and being con- figured to provide a respective one of the different trial output voltages,

a reference-voltage input port (80, 340), which is configured to receive a reference voltage and to provide the reference voltage to the signal generation unit (260), and

- voltage selection means (60, 420, 430) configured to select one voltage from a set of voltages comprising at least one of the trial output voltages and to feed the selected voltage as a reference voltage to a trial-voltage output port (85, 540) of the second interface unit (500), which is connected to the reference-voltage input port (80, 340) of the first interface unit (300); the second interface unit (500) further comprising at least one signal input port (90.1 , 90. n, 550, 560, 570), which is connected to the signal output port (90.1 , 90. n, 350, 360, 370) of the first interface unit (300) and configured to receive an information or control signal;

wherein the signal generation unit (260) is adapted to generate the at least one information or control signal with a signal level that is determined by the reference voltage,

and wherein a signal processing unit (440) is connected to the signal input port (90.1 , 90. n, 550, 560, 570) and configured to process information or control signals having a signal level that is determined by the reference voltage selected by the voltage selection means (420).

1 1. A method for operating an electronic signal-transmitting device (20, 200), the method comprising:

- providing at least two different trial output voltages in parallel to an electronic signal- processing device (30, 400), which is external to the signal-transmitting device (20, 200);

receiving a reference voltage from the external signal-processing device (30, 400);

providing the received reference voltage to a signal generation unit (260) of the electronic signal-transmitting device (20, 200);

- generating at least one information or control signal in the signal generation unit (260); and

providing the at least one information or control signal to the external electronic signal- processing device (30, 400) with a signal level that is determined by the received reference voltage.

12. The method according to claim 1 1 , wherein the reference voltage received is provided to the signal generation unit (260) only.

13. A method for operating an electronic signal-processing device (30, 400), the method comprising:

selecting, from a set of voltages comprising at least one trial output voltage received from an electronic signal-transmitting device (20, 200) that is external to the electronic signal- processing device (30, 400), one voltage as a reference voltage;

- outputting the reference voltage to the external electronic signal-transmitting device (20, 200);

receiving at least one information or control signal from the electronic signal-transmitting device (20, 200), the information or control signal having a signal level that is determined by the selected reference voltage; and

- processing the at least one information or control signal.

14. A method according to claim 13, wherein the set of voltages comprises at least one voltage different from the trial output voltages provided by the electronic signal-transmitting device (20, 200).

15. A method according to claim 13 or 14, wherein the trial voltage that best satisfies a predetermined voltage requirement of a signal processing unit of the electronic signal-processing device (30, 400) regarding the signal level of information or control signals delivered to the signal processing unit (440) is selected as the reference voltage.

16. An assembly comprising an electronic signal-transmitting device (20, 200) according to one of claims 1 to 4 and an electronic signal-processing device (30, 400) according to one of claims 5 to 9.

17. A method for operating an assembly of an electronic signal-transmitting device (20, 200) and an electronic signal-processing device (30, 400), which are coupled via respective interface units (300, 500), the method comprising:

providing at least two different trial output voltages in parallel from the electronic signal- transmitting device (20, 200) to the electronic signal-processing device (30, 400);

- selecting, at the signal-processing device (30, 400), from a set of voltages comprising at least one of the trial output voltages received from the electronic signal-transmitting device (20, 200), one voltage as a reference voltage;

providing the reference voltage from the electronic signal-processing device (30, 400) to the electronic signal-transmitting device (20, 200); providing, at the electronic signal-transmitting device (20, 200), the received reference voltage to a signal generation unit (260) of the electronic signal-transmitting device (20, 200); generating, at the electronic signal-transmitting device (20, 200), at least one information or control signal;

- providing the at least one information or control signal from the electronic signal- transmitting device (20, 200) to the electronic signal-processing device (30, 400) with a signal level that is determined by the reference voltage.