| 摘要 |
<p>PURPOSE:To perform an assured reset action by triggering a monostable multivibrator at the rise of a power supply recovery mode to deliver pulses and resetting a CPU with an OR between said pulse and a delay signal of a service interruption detecting signal. CONSTITUTION:The voltage supplied from a power supply terminal 14 is divided by a resistance and supplied to a voltage comparator 15. Input terminals IN and HYS have the hysteresis between a service interruption detection level and a power recovery detection level little higher than the service interruption detection level. The output of the comparator 15 is supplied to a monostable multivibrator 17 as well as to a delay circuit 20. Therefore it is possible to obtain the satisfactory pulse width by the multivibrator 17 despite a service interruption of a short time. This obtained pulse is used as a reset signal. Furthermore it is possible to eliminate the generation of a whisker-shaped waveform to the reset signal despite a high-speed actuation of a logical circuit 21 by obtaining an OR between the circuit 20 and the multivibrator 17.</p> |
