MM74C221

MM74C221 Dual Monostable Multivibrator November 1987 Revised January 1999 MM74C221 Dual Monostable Multivibrator General Description The MM74C221 dual monostable multivibrator is a monolithic complementary MOS integrated circuit. Each multivibrator features a negative-transition-triggered input and a positive-transition-triggered input, either of which can be used as an inhibit input, and a clear input. Once fired, the output pulses are independent of further transitions of the A and B inputs and are a function of the external timing components CEXT and REXT. The pulse width is stable over a wide range of temperature and VCC. Pulse stability will be limited by the accuracy of external timing components. The pulse width is approximately defined by the relationship tW(OUT) ≈ CEXT REXT. For further information and applications, see AN-138. Features s Wide supply voltage range: s Guaranteed noise margin: s High noise immunity: 4.5V to 15V 1.0V 0.45 VCC (typ.) fan out of 2 driving 74L s Low power TTL compatibility: Ordering Code: Order Number 74MMC221N Package Number N16E Package Description 16-Lead Plastic Dual-in-Line Package (PDIP), JEDEC MS-001, 0.300” Wide Connection Diagrams Timing Component Truth Table Inputs Clear L X X H H A X H X L ↓ B X X L ↑ H Outputs Q L L Q H H Pin Assignments for DIP H = HIGH Level = One HIGH level pulse L = LOW Level = One LOW level pulse ↑ = Transition from LOW-to-HIGH X= Irrelevant ↓ = Transition from HIGH-to-LOW L H Top ...