| 摘要 |
<p>PURPOSE:To effectively operate a reset circuit for a microcomputer by providing a time constant circuit between a battery power source and the power detection input of a reset device and slowly raising and quickly lowering the supply voltage given to the reset device. CONSTITUTION:A time constant circuit 3 is provided between a power input terminal 1 and a reset circuit 6. When a supply voltage VD supplied from the battery power source is given to the reset circuit 6 through the time constant circuit 3, the time constant for charging is small but is large for discharging because a diode D2 connected in parallel with a resistance R2 of the time constant circuit 3 is set in the charging direction of a capacitor C2. Consequently, the input voltage of the reset circuit quickly rises at the time of power-on and slowly falls at the time of a momentary interruption of the supply voltage VD. Thus, the reset circuit for the microcomputer is effectively operated.</p> |
