Battery pack

Abstract

The battery pack is provided with an analog front-end 2 that detects battery 1 voltage, and a micro-controller 3 connected to the analog front-end 2 that accepts analog voltage signals from the analog front-end 2 as input. The micro-controller 3 switches voltage signals input from the analog front-end 2 to determine failure of the analog front-end 2 or the micro-controller 3.

1 . A battery pack comprising:
 an analog front-end that detects battery voltage; and   a micro-controller connected to the analog front-end that accepts analog voltage signals input from the analog front-end;   
     wherein the micro-controller controls the analog front-end to determine failure of the analog front-end or the micro-controller. 
   
   
       2 . A battery pack as cited in  claim 1  wherein the micro-controller switches voltage signals input from the analog front-end to determine failure of the analog front-end or the micro-controller. 
   
   
       3 . A battery pack as cited in  claim 1  wherein the analog front-end is provided with input switches controlled by the micro-controller, and the micro-controller switches those input switches to determine failure. 
   
   
       4 . A battery pack as cited in  claim 3  provided with a plurality of series connected batteries; wherein the analog front-end is provided with input switches controlled by the micro-controller, and a voltage detection circuit that connects with the plurality of batteries via the input switches; and
 wherein the micro-controller switches the input switches to determine failure of the analog front-end voltage detection circuit.   
   
   
       5 . A battery pack as cited in  claim 4  wherein the micro-controller switches the input switches to detect the voltage of each battery and the total voltage of all the series connected batteries to determine failure of the analog front-end voltage detection circuit. 
   
   
       6 . A battery pack as cited in  claim 1  provided with a plurality of series connected batteries; wherein the analog front-end is provided with input switches controlled by the micro-controller, and a voltage detection circuit that connects with the plurality of batteries via the input switches; and
 wherein the micro-controller switches the input switches to short-circuit the input-side of the voltage detection circuit to determine input switch failure.   
   
   
       7 . A battery pack as cited in  claim 1  wherein the analog front-end is provided with input switches controlled by the micro-controller, and a voltage detection circuit that connects with the batteries via the input switches;
 the voltage detection circuit is provided with a difference amplifier to detect battery voltage; and the micro-controller controls the input switches to input battery voltage to the difference amplifier in a reversed polarity state, and in an un-reversed polarity state to determine voltage detection circuit failure from the output voltages.   
   
   
       8 . A battery pack as cited in  claim 7  wherein the analog front-end is provided with input switches controlled by the micro-controller, and a voltage detection circuit that connects with the batteries via the input switches;
 the voltage detection circuit is provided with a difference amplifier to detect battery voltage, and the difference amplifier has a standard voltage input to one of its input terminals;   and the micro-controller controls the input switches to input battery voltage to the difference amplifier in a reversed polarity state, and in an un-reversed polarity state to determine voltage detection circuit failure from the output voltages.   
   
   
       9 . A battery pack as cited in  claim 1  wherein the micro-controller is provided with an A/D converter to convert input analog voltage signals to digital signals, and with a first reference voltage for input to the A/D converter; a circuit is provided to input a second reference voltage, which is a different voltage than the first reference voltage, to the A/D converter; and the micro-controller switches between the first reference voltage and the second reference voltage to determine failure of the first reference voltage, the second reference voltage, or the A/D converter. 
   
   
       10 . A battery pack as cited in  claim 9  wherein the micro-controller is provided with an A/D converter to convert input analog voltage signals to digital signals, and with a first reference voltage circuit to input a first reference voltage to the A/D converter; the analog front-end is provided with a second reference voltage circuit to output a second reference voltage, which is a different voltage than the first reference voltage, to the micro-controller; and wherein the micro-controller switches between the first reference voltage and the second reference voltage to determine failure of the first reference voltage, the second reference voltage, or the A/D converter. 
   
   
       11 . A battery pack as cited in  claim 1  wherein the batteries are lithium ion rechargeable batteries.