MXPA06009476A - Battery circuit with non-volitable memory and thermistor on a single line - Google Patents

Abstract

A system (200) includes a battery charger (278) and a battery (202). The battery (202) includes a thermistor (230), a voltage identifying element (240), a switch (244), a memory device (232), and a battery data contact (228), connected to a data port of the memory device (232) and the voltage identifying element (240). The voltage identifying element (240) determines a voltage that controls the switch (244). When the switch (244) is enabled, the thermistor (230), connected to a battery clock contact (224), is active and a microprocessor (102) on the battery charger (278) reads the value of the thermistor (230) via an analog-to-digital converter. When the switch (244) is disabled, the thermistor (230) is switched out and the battery clock contact (224) is used to clock the memory device (232). The battery charger (278) has a data contact (226) for receiving the battery data contact (228) and a clock contact (222) for receiving the battery clock contact (224). The battery charger (278) further includes at least two switches (204,206), and the microprocessor (102) is programmed to selectively operate the switches (204,206).

Description

BATTERY CIRCUIT WITH NO-VOLAT L MEMORY AND THERMISTOR ON A SINGLE LINE FIELD OF THE INVENTION The present invention relates in general to stack charging systems and very specifically, to stack charging systems that identify stack information.

BACKGROUND OF THE INVENTION Many rechargeable batteries, such as those commonly found in cell phones, include a memory device in addition to the cells in the cell, such as an erasable programmable read-only memory (EPROM) or an electronically erasable programmable read-only memory (EEPROM). . The memory device stores important information regarding the stack in which it is incorporated. For example, the memory device may include information about the battery such as the type of battery used (example: whether the battery is a nickel-cadmium battery or a lithium battery), and specifications related to the charging regime that goes to be employed. In addition, the memory device can store "fuel level" information, which can be enabled by the host device (the device to which the battery supplies power) or by the charger to accurately determine the state of charge of the battery, such as a measurement based on the measured battery voltage. In addition to a memory device, many rechargeable batteries contain a thermistor. The incorporation of a thermistor in a rechargeable battery allows a microprocessor, in the battery charger, to monitor the temperature of the battery during the charging process. Therefore, the life of these batteries "Smart" is prolonged, thus ensuring that the cells in the battery are not overloaded, which could damage them permanently. However, batteries containing a memory device and a thermistor typically include separate contacts for each of these components. The use of "smart" batteries although useful, this is not without its shortcomings. One deficiency is that the typical "smart" stack configuration increases the number of contacts that the stack, the host device and the charger require to operate properly. An increased number of contacts in turn increase the cost and physical dimensions of the stack as well as the host device and the battery charger. Accordingly, there is a need for an "intelligent" battery circuit with a non-volatile memory device and thermistor which reduces the number of contacts required.

SUMMARY OF THE INVENTION The present invention relates to a battery charging system. The battery charging system includes a battery charger and a battery. The battery includes a thermistor, an element that identifies the voltage, a switch, a memory device, and a data contact of the battery, which is connected to a data port of the memory device and the element that identifies the voltage . The element that identifies the voltage determines a voltage at the data port and, in turn, controls the switch. When the switch is enabled, the thermistor, which is connected to the battery register contact, is active and a microprocessor in the battery charger reads the thermistor value through an analog-to-digital converter. When the switch is uninhabited, the thermistor is turned off and the battery log contact is used to register the memory device. The battery charger has a data contact to receive the data contact of the battery and a record contact to receive the battery registration contact. In another embodiment, the battery charger further includes at least two switches, and the microprocessor can be programmed to selectively operate the switches. By enabling a first switch, a first voltage is applied to the data port, enabling the thermistor. When the second switch is active, a second voltage is applied to the data port, disabling the thermistor and providing a registration signal to the memory device. The Erasable Programmable Read Only Memory (EPROM) or an Electronically Erasable Programmable Read Only Memory (EEPROM) have been shown to be conveniently used with the present invention. In addition, a Zener diode, resistance network, comparator or combination thereof has been shown to be conveniently used as a voltage identifying element.

BRIEF DESCRIPTION OF THE FIGURES The accompanying figures, in which similar reference numerals refer to identical elements or of similar functionality throughout the separate views and, which, together with the detailed description below, will be incorporated in, and form part of the description , serve to further illustrate various embodiments and to explain various principles and advantages, all in accordance with the present invention. Figure 1 is a block diagram illustrating an electronic device which incorporates a battery charging system using EEPROM and thermistor multiplexing, according to a preferred embodiment of the present invention. Figure 2 is a schematic circuit diagram of the battery charging system of Figure 1, according to a preferred embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED MODALITY Although the description concludes with the claims defining the characteristics of the invention that are considered as novel, it is believed that the invention will be better understood from the study of the following description in conjunction with the figures, in which reference numbers are included Similar. A method for preventing the increase in the number of contacts of the stack with custom memory Cls has been shown in U.S. Patent Application Number 10 / 247,160, Attorney's File No. IS01024ESG, entitled "Battery Circuit with Memory Device". Tres Terminales ", filed on September 18, 2002, and commonly assigned to Motorola, the complete teachings of which are incorporated by reference in their entirety in the present invention.

Exemplary Modality of an Electronic Device An exemplary hardware platform is now described in accordance with an exemplary embodiment of the present invention. Referring to Figure 1, the electronic device 100 is any device 100 with a screen that includes a wireless telephone, radio, PDA, computer, electronic organizer, and other device for sending messages, and an electronic timer. It can be appreciated that the terms "electronic device 100", "telephone", "radio", "host device" and "wireless device" can be used interchangeably throughout this document in reference to an exemplary electronic device. The electronic device 100 includes a controller 102, a memory 110, a non-volatile memory (program) 111 containing at least one application program 117, and an energy control system 120, which includes a power source interface. 115 to provide power to the device from a power source such as a battery (not shown) and a battery charger 278 (which will be discussed in more detail below) to intelligently charge the battery. The electronic device 100, in this example, is a wireless communication device. The wireless communication device transmits and receives signals to enable a wireless communication such as for a cellular phone, in a manner well known to those skilled in the art. For example, when the wireless communication device 100 is in a "receive" mode, the controller 102 controls a radio frequency (RF) transmit / receive switch 114 which couples an RF signal from an antenna 116 through the RF switch of transmission / reception (TX / RX) 114 to an RF receiver 104, in a manner well known to those skilled in the art. The RF receiver 104 receives, converts, and demodulates the RF signal, and then provides a baseband signal, for example, to the audio output module 103 and a transducer 105, such as a loudspeaker, in the device 100 to provide audio received a user. The operational reception sequence is under control of the controller 102, in a manner well known to those skilled in the art. In a "transmission" mode, the controller 102, for example, that responds to a detection of a user input (such as a user pressing a button or switch in a user interface 107 of device 100), controls the audio circuits and a microphone interface (which is not sample), and the transmit / receive RF switch 114 for coupling audio signals received from a microphone to transmitting circuits 112 and, therefore, the audio signals are modulated on an RF signal and coupled to the antenna 116 through the RF TX / RX switch 114 for transmitting an RF modulated signal in a wireless communication system (not shown). This transmission operation allows the user of the device 100 to transmit, for example, audio communication in the wireless communication system in a manner well known to those skilled in the art. The controller 102 operates the RF transmitter 112, the RF receiver 104, the RF TX / RX switch 114, and the associated audio circuits (not shown), according to the instructions stored in the program 111 memory. controller 102 is communicatively coupled to a user input interface 107 (such as a keyboard, buttons, switches, and the like) to receive user input from a user of device 100. It is important to note that the user input interface 107 in a modality is incorporated in the screen 109 as "GUI (Graphical User Interface) Buttons" as is known in the art. The user input interface 107 couples data signals (to the controller 102) based on keys pressed by the user. The controller 102 is sensitive to the data signals thereby causing the functions and features under control of the controller 102 to operate on the device 100. The controller 102 is also communicatively coupled to a screen 109 (such as a liquid crystal display) to display information to the user of the device 100. The present invention has been shown to be conveniently used with the U.S. Patent Application number 10 / 638,621 filed on August 11, 2003, entitled "System and Method for Verification of Pile", and the U.S. Patent Application number 10 / 459,271, filed June 11, 2003, entitled "", both commonly assigned to Motorola, and whose full descriptions are incorporated herein by reference in their entirety. Referring to Figure 2, a battery charging system 200 is illustrated. The battery charging system 200 includes a battery charger 278 and a battery 202. In a preferred embodiment, the battery charger 278 is incorporated into an electronic device. 100. Alternatively, the battery charger 278 is part of an independent device. For example, a separate charger can be a charger that receives power from a power source and converts the power to an appropriate level to charge a battery; typically, a separate charger does not perform another important function. In contrast, the electronic device 100 is any component that can not only load a stack but also perform other important functions. Appropriate examples of a guest device include a computer, a cordless telephone or a radio. Because the electronic device 100, in the preferred embodiment, is a telephone, the host device will be referred to hereinafter as a "telephone". In one embodiment, the battery charger 278 is coupled separately to the battery 202 for purposes of charging the battery 202 and / or energizing the electronic device 100. Specifically, the battery charger 278 includes a telephone charging contact positive 214, adapted to be coupled to a positive battery contact 218. The battery charger 278 also includes a negative telephone charging contact 216, adapted to be coupled to a negative battery contact 220. The telephone 100 can be energize directly from the positive battery contact 218 and the negative battery contact 220. In an alternative embodiment, the battery 202 includes a separate set of battery contacts (not shown) to provide power to the telephone 100. As will be discussed with In greater detail below, the battery charger 278 includes a data contact of the battery charger 226 to receive a data contact of the battery 228, in which a data port 238 terminates. of a memory device 232 and an element identifying the voltage 240. The battery charger 278 includes a battery charger register contact 222 adapted to receive a battery register contact 224, in which a battery charger port 224 terminates. register 242 of memory device 232 and a thermistor 230. Battery 202 includes one or more cells 234, which are discharged to provide power to host device 100. Battery charger 278 reloads cells 234 when cells 234 are depleted . In addition, the cells 234 include a positive terminal 254 coupled to the positive cell contact 218 to provide the positive voltage B + to the host device through the positive cell node 260. In addition, the cells 234 include a negative terminal 256, coupled to a circuit security 252 which avoids an overload or low charge of the cells 234. In one embodiment, the security circuit 252 can be coupled to the negative battery contact 220, and in turn, provide a negative voltage (B-) or point a ground to the battery charger 278 through the negative battery node 258. The battery charger 278 includes a microprocessor or microcontroller 102 and a pair of switches 204, 206, which will determine the function of the battery charger's record contact. battery 222. The data contact of the battery charger 226 is coupled to an input / output (I / O) port 212 on the microprocessor 102, and likewise is coupled to the switch 204 and the switch 20 6 through a pair of adjustment resistors 208, 210. Switch 204, when closed, adjusts the voltage at port 212 to the voltage level established by a first voltage source 262 having a voltage level observed as VI (5.5V in a preferred embodiment), through resistor 208. Switch 206, when closed, adjusts the voltage at port 212 to the voltage level established by a second voltage source 264, which has a voltage level. observed as V2 (2.775V in a preferred embodiment), through resistor 210. Only one of switch 204 and switch 206 can be closed at any given time. The battery charger register contact 222 is coupled to the microprocessor 102 through a 1/0 port 266. Additionally, the battery charger register contact 222 can also be coupled to the microprocessor 102 through an analog converter. -a-digital (A / D) 236. As noted above, the battery 202 includes a thermistor 230, an element identifying the voltage 240 and a memory device 232. The element identifying the voltage 240 and the thermistor 230 can be coupled by means of a switch 244. The switch 244 can be a transistor device, such as an FET, with the drain coupled to the thermistor 230, the source coupled to the negative cell node 258, and the door coupled to the element identifying the voltage 240 and a resistor 246 at the node 268. The charger of the Stack works as follows. To read or write to the memory device 232, the switch 206 would be closed and the switch 204 open, placing V2 (2.7775V) on the data contact of the battery charger 226. The element identifying the voltage 240 uses the voltage in the data contact of the stack 228 ("data line") to establish a control voltage in the node 268. The element identifying the voltage 240 may include a Zener diode, a resistance separator network, a comparator, or any other device that identifies voltage commonly known to those skilled in the art. When the voltage level is not low enough or high enough to enable the switch 244, the thermistor 230 is turned off at the battery register contact 224 ("registration line"). In this mode, host device 100 establishes communication with memory device 232 through ports 1/0212 and 266 as usual. Although the use of the registration line 224, in this mode, it is used to read the value of the thermistor 230. In another mode (not shown), the functions of the registration and data lines are inverted, wherein a The voltage is placed on the data line 228 and the value of the thermistor 230 is read from the data line as understood by those skilled in the art. To read the value of the thermistor 230, the switch 204 would be closed and the switch 206 would be open, placing VI (5.5V) on the data line 228. The element identifying the voltage 240 then enables the voltage at the node 268 sufficiently high or low to allow the 244 switch to drive. In this mode, the thermistor 230 is switched on the registration line 224, allowing the microprocessor 102 to access the value of the thermistor 230 through an analog-to-digital converter 236 as it is normally read. In this form, the radio or electronic device 100 selectively reads or writes to the memory device 232 or reads the thermistor 230 without any interaction between the memory device 232 and the thermistor 230. It is important to note that, although the switch 244 is shown as a PNP transistor, for those skilled in the art, NPN transistor types could also be substituted within the true scope and spirit of the invention. In this arrangement, the power node 249 of the memory device 232 is diverted directly from the positive stack node 260 through the resistor 250. The ground node 248 of the memory device is directly coupled to the negative stack node 248. It will be apparent to those skilled in the art that this configuration means that the memory device 232 is continuously drawing current from the cells of the stack 234. However, because the reservation current of a typical EPROM or EEPROM is located in the Single-digit microamp range, this current leak should be quite insignificant. In one arrangement, the battery charger 278 selectively reads the memory device 232 or a value from the thermistor 230. For example, this value may be the impedance of the thermistor 230, which is used by the microprocessor 102 of the battery charger. 278 to monitor the temperature of the stack 202 while it is being charged. As another example, the memory device 232 is an EPROM that stores information related to the stack 202, such as the type of battery, the charging scheme to be employed and the state of charge of the battery 202. The microprocessor 102 of the battery charger 278 reads the memory device 232 and uses this information for the purpose to ensure that stack 202 is efficiand properly charged. Of course, it will be understood that the memory device 232 is not limited to being an EPROM, since the memory device is any other suitable componcapable of storing information, such as an EEPROM, non-volatile RAM, and FLASH memory. Moreover, the memory device 232 is not, in any way, limited only to storing information related to the state of the stack 202, since the memory device 232 stores any other appropriate type of data. The actual functionality of stack 202 is increased by replacing the EPROM in use in currstack designs with an EEPROM, which increases the overall functionality of stack 202 by allowing stack information such as, but not limited to, load cycles, date of last charge, power supply used, maximum charge curr maximum charge voltage, and temperature to be written to the EEPROM. This information is used to help determine the root cause of causes of return and possible causes of safety, thereby reducing developmand warranty costs. In addition, by allowing the customized EPROM from a single source, in most currdesigns, to be replaced by an EEPROM in standard, lower cost warehouse, the presinvon reduces the overall cost of stack 202. Additionally, using the line of data 228 to selectively switch on the thermistor 230 on the registration line 224, the radius 100 is able to: 1) read the battery temperature, and 2) read / write the EEPROM without adding an additional contact to achieve this capacity. This allows the configuration of four standard battery contacts to be maintained. Although the preferred embodim of the invon have been illustrated and described, it will be apparthat the invon is not limited thereto. Those skilled in the art will appreciate that numerous modifications, changes, variations, substitutions and equival can be made without departing from the spirit and scope of the presinvon, as defined in the appended claims.

Claims (1)

1. NOVELTY OF THE INVENTION Having described the present invention, it is considered as a novelty and, therefore, the content of the following is claimed as a priority: CLAIMS 1. - A battery system comprising: a battery; a thermistor, with a first end and a second end; a memory device; a plurality of contacts adapted to be communicatively coupled with a stack charger including a stack data contact, a stack register contact; and wherein the battery charger selectively executes at least one of registering the memory device and reading a value of the thermistor, through a register contact of the battery charger and the data contact of the battery. 2. - The system according to claim 1, characterized in that the memory device comprises: a data port communicatively coupled to the data contact of the battery and the first end of an element that identifies the voltage; and a registration port communicatively coupled to the battery registration contact and to the first end of the thermistor. 3. - The system according to claim 2, characterized in that the element that identifies the voltage, further comprises a second end, the first end of the element that identifies the voltage is communicatively coupled to the data contact of the battery, to identify a voltage in the battery data contact; and a switch, communicatively coupled between the second end of the thermistor and the second end of the voltage identifying element, for selectively reading a thermistor value and outputting a registration signal to a recording port of the memory device. . - The system according to claim 1, characterized in that the memory device is one of an erasable programmable read-only memory (EPROM), an electronically erasable programmable read-only memory (EEPROM), a non-volatile random access memory (RAM) and a FLASH memory. 5. - The system according to claim 3, characterized in that the element that identifies the voltage is one of a Zener diode, a resistance separating network, and a comparator. 6. - A battery charging system comprising: a battery charger; a battery; a thermistor, with a first end and a second end; a memory device; a plurality of contacts adapted to be communicatively coupled with the battery charger including a battery data contact, a battery register contact; and a memory device; wherein the battery charger selectively executes at least one of registering the memory device and reading a value of the thermistor, through one of the log contact of the battery charger and the data contact of the battery. 7. - The system according to claim 6, characterized in that the memory device is one of an erasable programmable read-only memory (EPROM), an electronically erasable programmable read-only memory (EEPROM), a random access memory is not -Vagile (RAM) and a FLASH memory. 8. - The system according to claim 6, characterized in that the memory device comprises: a data port communicatively coupled to the data contact of the battery and the first end of an element that identifies the voltage; and a register port communicatively coupled to the battery register contact and the first end of the thermistor. 9. - The system according to claim 8, wherein the element that identifies the voltage further comprises a second end, the first end of the element that identifies the voltage is communicatively coupled to the data contact of the battery, to identify a voltage in a stack data contact; and a switch, communicatively coupled between the second end of the thermistor and the second end of the voltage identifying element, for selectively reading a thermistor value and outputting a registration signal to a recording port of the memory device. 10. The system according to claim 9, characterized in that the element that identifies the voltage is one of a Zener diode, a resistance separating network, and a comparator.