74LS123N DIP IC

These dc triggered multivibrators feature pulse width control by
three methods. The basic pulse width is programmed by selection of
external resistance and capacitance values. The LS122 has an internal
timing resistor that allows the circuits to be used with only an external
capacitor. Once triggered, the basic pulse width may be extended by
retriggering the gated low-level-active (A) or high-level-active (B)
inputs, or be reduced by use of the overriding clear.
? Overriding Clear Terminates Output Pulse
? Compensated for VCC and Temperature Variations
? DC Triggered from Active-High or Active-Low Gated Logic Inputs
? Retriggerable for Very Long Output Pulses, up to 100% Duty Cycle
? Internal Timing Resistors on LS122