SOURCE VOLTAGE DROP PROTECTING DEVICE

摘要

PROBLEM TO BE SOLVED: To reduce the power consumption of a source voltage drop protecting circuit protecting an electric system which uses a battery as its power source by detecting the source voltage dropping owing to battery consumption in such a case. SOLUTION: When a power-ON signal is inputted from an input key 2, a high-level signal is sent to an ON-signal inhibiting device 3 and a voltage detecting circuit 1 detects the voltage of the battery 4. When the detected voltage is lower than a specific value, the voltage detecting device 1 sends a low- level signal to an ON-signal inhibiting device 3. The voltage detecting circuit 1 sends a high-level voltage to the ON-signal inhibiting device 3 when the detected voltage is higher than the specific value. The ON-signal inhibiting device 3 transmits a power-ON input from the input key 2 only when the power-ON signal is inputted and the voltage of the battery 4 is higher than the specific value.