SN54LV221A,SN74LV221A,pdf(DUAL

The ’LV221A devices are dual mulTIvibrators designed for 2-V to 5.5-V V_CC operaTIon. Each mulTIvibrator has a negaTIve-transition-triggered (A\) input and a positive-transition-triggered (B) input, either of which can be used as an inhibit input.

These edge-triggered multivibrators feature output pulse-duration control by three methods. In the first method, the A\ input is low and the B input goes high. In the second method, the B input is high and the A\ input goes low. In the third method, the A\ input is low, the B input is high, and the clear (CLR\) input goes high.

The output pulse duration is programmable by selecting external resistance and capacitance values. The external timing capacitor must be connected between C_ext and R_ext/C_ext (positive) and an external resistor connected between R_ext/C_ext and V_CC.