Pin Name Description
1 ground 0 V supply
2 trigger When the pin voltage falls below 0.33 Vcc, the timer is triggered and the output goes high. In the monostable configuration a high to low transition on the trigger pin starts the timer.
3 output The output pulses during astable operation and goes high for a set time in monostable operation.
4 reset If reset is not used, connect it to Vcc. If reset falls, a high output will be forced low.
5 control voltage For reliable operation add a 10 nF capacitor to ground on this pin.
6 threshold Detects when the voltage on the timing capacitor rises above 0.66 Vcc and resets the output when this happens.
7 discharge Provides a discharge path from the timing capacitor to ground when the output is low.
8 Vcc Positive power supply voltage.

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