
STMicroelectronics
DESCRIPTION
The M54/74HC221/221A are high speed CMOS MONOSTABLE multivibrators fabricated with silicon gate C2MOS technology. It achieves the high speed operation similar to equivalent LSTTL while maintaining the CMOS low power dissipation. There are two trigger inputs, AINPUT (negative edge) and B INPUT (positive edge). Triggering on the B input occurs at a particular voltage threshold and is not related to the rise and fall time of the applied pulse.
■ HIGH SPEED
tPD = 25 ns (TYP) at VCC = 5V
■ LOW POWER DISSIPATION
STANDBYSTATE ICC=4 µA (MAX.) AT TA=25°C
ACTIVESTATE ICC =700µA (MAX.)AT VCC=5V
■ HIGH NOISE IMMUNITY
VNIH = VNIL = 28 % VCC (MIN.)
■ OUTPUT DRIVE CAPABILITY
10 LSTTL LOADS
■ SYMMETRICAL OUTPUT IMPEDANCE
IOH = IOL = 4 mA (MIN.)
■ BALANCED PROPAGATION DELAYS
tPLH = tPHL
■ WIDE OPERATING VOLTAGE RANGE
VCC (OPR) = 2 V TO 6 V
■ WIDE OUTPUT PULSE WIDTH RANGE
tWOUT = 150 ns ∼ 60 s OVER AT VCC = 4.5 V
■ PIN AND FUNCTION COMPATIBLE WITH 54/74LS221