DESCRIPTION

The M54/74HC393 is a high speed CMOS DUAL BINARY COUNTER fabricated in silicon gate C2MOS technology. It has the same high speed performance of LSTTL combined with true COMS low power consumption.

This counter circuit contains independent ripple carry counters and two 4-bit ripple carry binary counters, which can be cascated to create a single divide by 256 counter.

Each 4-bit counter is incremented on the high to low transition (negative edge) of the clock input,and each has an independent clear input. When clear is set to low all four bits of each counter are set to a low level. This enables count truncation and allows the implementation od divide by N counter configurations.

All inputs are equipped with protection circuits against static discharge and transient excess voltage.

■ HIGH SPEED fMAX = 72 MHz (TYP.) AT VCC = 5 V

■ LOW POWER DISSIPATION ICC = 4 µA (MAX.) AT TA = 25 °C

■ 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

■ PIN AND FUNCTION COMPATIBLE WITH 54/74LS393