The VHC393 is an advanced high speed CMOS 4-bit Binary Counter fabricated with silicon gate CMOS technology. It achieves the high speed operation similar to equivalent Bipolar Schottky TTL while maintaining the CMOS low power dissipation. It contains two independent counter circuits in one package, so that counting or frequency division of 8 binary bits can be achieved with one IC. This device changes state on the negative going transition of the CLOCK# pulse. The counter can be reset to "0" (Q₀-Q₃ = "L") by a HIGH at the CLEAR input regardless of other inputs.

An input protection circuit ensures that 0V to 7V can be applied to the input pins without regard to the supply voltage. This device can be used to interface 5V to 3V systems and two supply systems such as battery back up. This circuit prevents device destruction due to mismatched supply and input voltages.

• High Speed: f_MAX = 170 MHz (typ) at T_A = 25°C
• Low power dissipation: I_CC = 4 µA (max) at T_A = 25°C
• High noise immunity: V_NIH = V_NIL = 28% V_CC (min)
• Power down protection is provided on all inputs
• Pin and function compatible with 74HC393