| 摘要 |
PROBLEM TO BE SOLVED: To provide a voltage detection device capable of reducing costs without requiring a negative power supply. SOLUTION: A voltage detection circuit 12 includes operational amplifiers 120a and 121a, a battery 122, and a voltage circuit 123. Inverting input terminals and noninverting input terminals of the operational amplifiers 120a and 121a are set off by the voltage circuit 123 to the positive side with respect to the ground GND. Even when a voltage input to an input terminal becomes a negative voltage with respect to the ground GND, a voltage of the input terminal does not therefore become a negative voltage with respect to the ground GND. It is therefore possible to operate the operational amplifiers 120a and 121a only by the battery 122 which supplies a positive voltage with respect to the ground GND. The need for a negative power supply for operating the operational amplifiers 120a and 121a is thereby eliminated to reduce costs. COPYRIGHT: (C)2011,JPO&INPIT |
