HD74HC221 Datasheet PDF

Hitachi HD74HC221

The HD74HC221 can be triggered on the positive transition of teh clear while A is held low and B is held high. This device is a non-retriggerable, and therefore cannot be retriggered until the output pulse times out. The output pulse equation is simply: tW = 0.7·(Rext)·(Cext) Features • • • • • High Speed Operation High Output Current: Fanout of 10 LSTTL Loads Wide Operating Voltage: VCC = 2 to 6 V Low Input Current: 1 µA max Low Quiescent Supply Current Function Table Inputs Clear L X X H H L A X H X L H H B X X L Outputs Q L L L Q H H H HD74HC221 Pin Arrangement 1A 1B CLR1 1Q 2Q Cext 2 2 Rext/ Cext GND 1 2 3 4 5 Q CLR Q Q 16 15 14 13 12 11 10 9 (Top view) VCC 1 Rext/ Cext 1 Cext 1Q 2Q 2CLR 2B 2A Q CLR 6 7 8 Logic Diagram VCC Rext Cext Cext Rext /Cext A B Q Clear Q Q Clear 2 HD74HC221 DC Characteristics...