The circuit shown above provides output signals at a pre-

scribed time interval from a time reference and automatically

resets the output when the input returns to ground. Consider

the case of V

ground. This implies that the outputs of comparators 1, 2,

and 3 are also at ground. When an input signal is applied,

the output of comparator 4 swings high and C charges expo-

nentially through R. This is indicated above. The output volt-

ages of comparators 1, 2, and 3 swtich to the high state

when V

A small amount of hysteresis has been provided to insure

fast switching when the RC time constant is chosen to give

long delay times.

Time Delay Generator

DS012347-32

FIGURE 9. Time Delay Generator

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