KR200394660Y1 - Usb connector with card detector - Google Patents

Abstract

A universal serial bus (USB) connector is provided with a card detector suitable for low power capacity systems. The USB connector includes at least a power pad, a D- signal pad, a D + signal pad, a ground pad, and a device insertion detection pad. The device insertion detection pad and the ground pad are disposed corresponding to the ground pad of the external USB interface device such that the device insertion detection pad and the ground pad are simultaneously grounded when an external USB interface device is inserted into the USB connector. Power supply to the USB connector is controlled via a short signal provided by the device insertion detection pad. The USB connector of the present invention can be used to operate the VBUS power converter in an immediate manner while the external device is not plugged into the USB connector and to drive the USB connector in standard operation with very little power loss.

Description

USB connector with card detector {USB CONNECTOR WITH CARD DETECTOR}

The present invention relates to an improved USB connector, and more particularly to an energy-efficient USB connector.

To facilitate the connection of different system terminal devices with various external peripherals, four international companies (including Compaq, Intel, Microsoft and NEC) have developed the Universal Serial Bus (USB) interface in 1998. have. These peripherals are easy to use because the Microsoft Windows 98 operating system has begun providing built-in programs to drive USB interface peripherals. As a result, the applications of USB products are gradually expanding.

In general, the USB interface uses differential serial signals to provide serial data for physical layer transmission. In addition, the USB interface suitably uses a variety of and highly flexible communication protocols to support different types of devices. The USB interface provides a small number of signal pads (power pad VBUS, ground pad GND, signal pad D +, and only four signal pads including another signal pad D-), providing power, High transfer rates (classified as low-speed of 1.5 Mbit / sec, full-speed of 12 Mbit / sec, high-speed of 480 Mbit / sec), and hot-plug means (system shutdown or machine reboot required due to expansion unit installation) And many more). With many of these advantages, USB products are gradually replacing the first generation expansion interface, which includes parallel ports and serial ports in some older computer systems. Recently, various forms of USB peripheral products have been produced for collecting data, storing data, capturing / scanning images, and printing documents.

In the past, the USB interface was considered as an additional device of a personal computer system for connecting external devices. Since the USB interface was designed primarily to facilitate the operation of personal computers, there was no way for two peripheral devices connected through the USB interface to exchange data with each other. Because of this, USB-IF (the USB Attendant Forum, an organization that implements and develops the USB standard) has been developing USB standards for peripherals in computer systems, as well as newly developed digital portable products (eg, USB OTG standards). For example, DSC, PDA, smartphones) have been provided. This new standard allows peripheral interface products to exchange data with each other according to a set of specific rules. Thus, portable devices communicate with each other via communication control without the need for arbitration through a central computer system, which is an advance in the application mode of portable devices.

In the design of the USB interface, system terminal devices must rely on electrical changes in the signal lines D + and D- to detect the presence of any externally plugged devices in the expansion interface. If no devices are plugged into the expansion interface, the D + and D- signal pads of the USB interface will have near zero potential. If the low-speed device is plugged into the expansion interface, the low-speed device will connect the D-signal pad to a 3.3V supply. Because of this, the system terminal device will detect the insertion of the low-speed device through the voltage change of the D- signal line. If a full-speed device is plugged into the expansion interface, the full-speed device will connect the D + signal pad to a 3.3V supply. Thus, the system terminal device will detect the insertion of the full-speed device through the voltage change of the D + signal line. Finally, if the high-speed device is plugged into the expansion interface, the external device will use the full-speed mode of operation to inform the system terminal device about the presence of the plugged full-speed device. Then, via the software interface protocol, it is verified whether high-speed communication is supported by both sides. Only upon verification completion will the devices enter the high-speed operating mode.

A system terminal device with a USB interface must rely on changes in electrical signals from the external device to detect the presence of plugged external devices and to determine operating attributes. Because of this, the characteristics of the electrical supply by the USB interface must be repeatedly triggered by the transfer of the operating voltage from the VBUS power pad to the external device so that the external device is ready to raise the D + / D- interface pad to a high potential. . In short, some electrical devices inside the system terminal device must operate even if the external device is not plugged into the system. This means power is always and forever consumed.

When the above-mentioned design is used in a desktop computer system or notebook computer system connected to a fixed power supply, the design always permits detection of changes in the D + / D- signal because an unlimited power supply is provided. However, when the aforementioned design is applied to the aforementioned USB-OTG interface of portable digital devices (e.g. PDAs or smartphones) with limited power supply due to volume and weight considerations, the power supply of the portable device may be Too much power will be required.

1 shows a circuit diagram of a portable device such as a PDA or digital camera having a CF memory card functioning as a storage device and a USB interface functioning as a signal transmission center. The portable device can always be connected to a printer having a USB interface for printing data stored internally on paper. The portable device has a USB connector CONN2 for connecting to the USB interface of the printer and a USB interface controller U2 for operating the USB connector CONN2. Voltage converter circuits (U4, US3) electrically connected to the USB interface connector (CONN2) and the USB interface controller, for supplying power to the external device in the USB connector (CONN2) and for determining the type of external device to which the portable device is plugged. ) Is installed in the portable device. In addition, to ensure proper response when the external device is plugged in and to supply power for driving the external device, the voltage converters U4 and U3 inside the portable device continue to provide corresponding operating voltages to the internal devices. In order to do this, a voltage conversion operation must be performed. On the other hand, the voltage level of the external device must be kept checked for some pull-up voltage to determine the type of connection device. In addition, since the USB interface controller U2 must always be in a standby state, power cannot be cut off for the USB interface controller U2. In other words, power supplied to the USB interface-related circuit and the controller inside the portable device should be provided even if the external device is not connected.

In sum, according to the aforementioned phenomena, the design leads to quite the opposite result for the purpose of producing a lightweight, power-efficient, low battery power portable device. Since the operating period of the battery is reduced due to constant power consumption, the standby period of the battery can be significantly shortened.

Several specific issues must be considered to counteract the reduction in battery life due to the setup of the USB interface in the portable device. For example, in the absence of an external device, the power supplied to some devices inside a portable device such as a voltage converter and a power supply can be completely shut off.

It is an object of the present invention to provide a USB connector that can counteract the reduction in battery life due to the setup of a USB system interface in a portable device.

Another object of the present invention is to provide a USB connector with an additional device insertion detection mechanism that does not provide the external device with the operating voltage or power required to drive the USB interface controller when the external device is not inserted into the USB connector.

Another object of the present invention is to provide a USB connector with an additional device insertion detection mechanism such that the power supply of the portable device is turned on after the external device is inserted into the USB connector.

In order to achieve the above objects and advantages and according to the object of the present invention as embodied and described broadly herein, the present invention provides a USB connector. USB connectors can be placed in low power capacity systems. The USB connector includes at least a power pad, a D- signal pad, a D + signal pad, a ground pad, and a device insertion detection pad. The device insertion detection pad and the ground pad are disposed corresponding to the ground pad of the external USB interface device such that the device insertion detection pad and the ground pad are simultaneously grounded when the external USB interface device is inserted into the USB connector. For this reason, the power supply to the USB connector is controlled through the device insertion detection pad.

Alternatively, the device insertion detection pad and power pad may be disposed corresponding to the power pad of the external USB interface device such that the power supply to the USB connector is controlled through the level transition of the device insertion detection pad.

The present invention also provides an application system having a USB connector. The application system includes at least a USB connector and an application circuit. The USB connector includes at least a power pad, a D- signal pad, a D + signal pad, a ground pad, and a device insertion detection pad. The device insertion detection pad determines whether or not the operating power required to drive the external device has been provided through the USB connector.

The application circuit includes at least a power supply controller and a power converter circuit respectively connected to the device insertion detection pad.

When an external USB interface device is inserted such that the device insertion detection pad is connected to ground to a low potential, the device insertion detection pad generates an insertion control signal to drive the power controller and the power converter circuit. Thus, the USB connector and its corresponding USB interface controller are operated to perform standard operating procedures. In contrast, in the absence of an external USB interface controller in the USB connector, neither the power controller nor the power converter circuit receives any insertion control signal and is therefore in a shutdown state. Therefore, the USB connector and its corresponding USB interface controller are not enabled.

It is to be understood that both the foregoing general description and the following detailed description are exemplary, and that additional descriptions of the claimed invention are provided.

Reference numerals are indicated in detail in preferred embodiments of the present invention, examples of which are indicated in the reference figures. In any case, like reference numerals are used in the description and the drawings to refer to the same or like parts.

In the following, a system terminal device having a CF storage interface and a USB transmission interface is used as an example for explaining the features and functions of the present invention. However, one of ordinary skill in the art will readily appreciate the other advantages and performances of the present invention in accordance with the teachings herein. The present invention may also be implemented or applied through other embodiments. In addition, the detailed description may be modified or changed according to aspects and applications without departing from the scope, technical spirit and other objects of the present invention.

2 is an application circuit diagram of a USB connector having an additional signal detection device according to an embodiment of the present invention. The USB connector of the present invention is implemented in a system terminal device. However, the "system terminal device" is not limited to a computer host system and includes an external device having a USB connector such as a PAD or a mobile phone.

The application circuit shown in FIG. 2 is a low voltage dropout (LVD) that converts the supply voltage to provide the voltages required by CF interface storage controller U1, USB interface controller U2, U1 and U2. Regulator U3, power converter circuit U4, power controller U5, CF interface storage connector CONN1 to achieve interface connectivity, and USB interface connector CONN2. Since the CF interface storage device U1 and the CF interface connector CONN2 are related to the storage device of the system terminal device and are not of major interest in the present invention, the detailed description is omitted here.

In the present invention, the power converter circuit U4 and the power controller U5 and the additional device insertion detection pad 115b in the aforementioned USB connector are electrically connected and the USB interface controller U2 and the D- and D + signals. Signal transmission is performed by electrically connecting the pads. Depending on whether or not the device insertion detection pad 115b has been operated, power required to operate the external device is provided by the USB connector CONN2. The power controller U5 is electrically connected to the USB interface controller U2, and the power converter circuit U4 is electrically connected to the power pad 110 of the USB connector CONN2. When the external device is plugged in, the device insertion detection pad 115b generates an insertion control signal to operate the power supply controller U5 and the power converter circuit U4. As a result, the corresponding USB interface controller U2 and the USB connector CONN2 are operated to perform a standard operating procedure.

In the absence of an external device plugged into the USB connector CONN2, no insertion control signal is generated. For this reason, the power supply controller U5 and the power converter circuit U4 are in their original 'shut down' state. As a result, the USB interface controller U2 corresponding to the USB connector CONN2 and the USB connector CONN2 is not activated.

3 is a USB connector with an additional signal detection device according to an embodiment of the present invention. As shown in FIG. 3, the USB connector 1 has a VBUS signal pad 110, a D- signal pad 111, a D + signal pad 112, a ground pad 115, and a device insertion detection pad 115b. It includes. The VBUS signal pad 110, D- signal pad 111, D + signal pad 112, and ground pad 115a are set up from TOP to BOTTOM according to the USB standard specification. The ground pad 115a and the insertion detection pad 115b are arranged to correspond with the ground pad of the external device so that the insertion detection pad 115b can detect any plugged external device. When an external device (not shown) is plugged in, the insertion detection pad 115b generates a signal to notify the system terminal device and operates the USB interface module and the VBUS power supply. The type of plugged external device is then determined to initiate the standard mode of operation. On the other hand, in the absence of any plugged external device, insertion detection pad 115b drives the system terminal device to close the VBUS power supply and reduce the overall power consumption of the system.

After the USB connector 1 verifies the presence of the external device via the insertion detection pad 115b, the system is immediately notified to operate the power converter circuit U4 for supplying power to the power pad 110. FIG. Thus, the power source required to perform electrical communication between the external device and the USB connector 1 is provided to the external device.

The provision of a signal detection device does not cause any change in the USB standard specification. That is, as long as the ground pad of the USB connector and the device insertion detection pad coincide with the positions of the ground pad GND of the corresponding external device, the power supplied to the VBUS and the USB connector is for detecting the presence of the external device in the present invention. It can be controlled through a change in electrical potential. For example, a metal that originally acts as a ground pad to form a short circuit to ground to create a low potential at the insertion detection pad 115b and the ground pad 115a after the external device is plugged into the USB connector 1. The membrane 115 is separated into two. A portion of the metal film 115 acts as the ground pad 115a for the USB connector 1, while the remaining portion of the metal film 115 acts as the insertion detector 115b. Using a similar principle of operation, the detection of the external device plugged into the USB interface 1 and the provision of a series of power supplies are based on the information provided by the high / low transition of electrical potential.

It is apparent that the mechanical structure for implementing the device insertion detection pad in the present invention is not limited to the aforementioned. Other structures or locations can also be used that can produce similar results. For example, the device insertion detection pad may be a movable foil, which is pushed when an external device is inserted into a USB connector, resulting in detection to inform the system of the insertion of the external device. The signal is generated.

It is apparent to those skilled in the art that the structure of the present invention can be variously modified or changed without departing from the scope or technical spirit of the present invention. In view of the foregoing, it is intended that the present invention cover modifications and variations of this invention provided they come within the scope of the following claims and their equivalents.

In summary, both the newly added insertion detection pad and ground pad GND are electrically connected to the ground pad of the external device. For this reason, the application circuit closes the power supply and the USB interface controller provided from the USB connector in the absence of the device plugged into the USB connector. On the other hand, after the external device is plugged into the USB connector, the application circuit immediately operates all relevant electronic devices to initiate a standard operating procedure. The USB connector of the present invention can be applied to immediately operate the VBUS power converter circuit and drive the USB connector in a standard operating process without causing energy consumption in the absence of external devices. That is, the present invention can reduce the power consumed by the electronic devices associated with the USB connector and can extend the useful life of the battery. Accordingly, the USB system with additional signal detection device and energy-saving function according to the present invention is suitable for low power capacity portable devices including mobile phones, PDAs, smart phones, digital cameras, and the like.

1 is an application circuit diagram of an adapter of a typical CF / USB interface storage device.

2 is an application circuit diagram of an adapter of a CF / USB interface storage device according to an embodiment of the present invention; And

3 is a USB connector having an additional signal detection device according to an embodiment of the present invention.

Claims (4)

A universal serial bus (USB) connector having a signal detection device disposed inside a low power capacity system terminal device, At least a power pad; D- signal pad; D + signal pads; A ground pad and a device insertion detection pad; The insertion detection pad and the ground pad, When an external device is inserted into the USB connector, the ground pad of the external device is disposed corresponding to the ground pad of the external device such that the device insertion detection pad and the ground pad of the USB connector are simultaneously shorted to ground, Therefore, the USB connector characterized in that it controls or does not control the power provided by the USB connector. The method of claim 1, And said grounding pad and said insertion detecting pad are cutouts of a metal foil which originally acts as a grounding terminal. In an application system having a USB connector and a USB interface controller, At least a power pad, a D- signal pad, a D + signal pad, a ground pad, and a device insertion detection pad, wherein the D- and D + signal pads are electrically connected to the USB interface controller to perform signal transmission, and the device insertion The detection pad includes: a USB connector actuating to determine whether the USB connector provides power for driving an external device; An application circuit having at least a power controller and a power converter circuit; The power controller is electrically connected to the device insertion detection pad and the USB interface controller, The power converter circuit is electrically connected to the device insertion detection pad and the power pad so that the device insertion detection pad generates an insertion control signal in the presence of a plugged external device to provide power to the power controller and the power converter circuit. Actuate and, as a result, the corresponding USB interface controller and the USB connector to actuate a standard operating procedure. The method of claim 3, wherein Wherein said ground pad and said insertion detection pad are essentially cutouts of a metal foil acting as a ground terminal.