DESCRIPTION

The M74HC393 is an high speed CMOS DUAL BINARY COUNTER fabricated with silicon gate C2MOS technology.

This counter circuit contains independent ripple carry counters and two 4-bit ripple carry binary counters, which can be cascaded 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 of divide by N counter configurations.

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

■ HIGH SPEED : fMAX = 79 MHz (TYP.) at VCC = 6V

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

■ HIGH NOISE IMMUNITY: VNIH = VNIL = 28 VCC (MIN.)

■ SYMMETRICAL OUTPUT IMPEDANCE: |IOH| = IOL = 4mA (MIN)

■ BALANCED PROPAGATION DELAYS: tPLH ≅ tPHL

■ WIDE OPERATING VOLTAGE RANGE: VCC (OPR) = 2V to 6V

■ PIN AND FUNCTION COMPATIBLE WITH 74 SERIES 393