The TC74VHC 161 and 163 are advanced high speed CMOS
SYNCHRONOUS PRESETTABLE 4 BIT BINARY
COUNTERS fabricated with silicon gate C2MOS technology.
They achieve the high speed operation similar to equivalent.
Bipolar Schottky TTL while maintaining the CMOS low
power dissipation.
The CK input is active on the rising edge. Both LOAD and
CLR inputs are active on low logic level.
Presetting of each IC's is synchronous to the rising edge of
CK.
The clear function of the TC74VHC163 is synchronous to CK,
while the TC74VHC161 are cleared asynchronously.
Two enable inputs (ENP and ENT) and CARRY OUTPUT
are provided to enable easy cascading of counters, which
facilitates easy implementation of n bit counters without
using external gates.
An input protection circuit ensures that 0 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.

FEATURES:
• High Speed
.fMAX = 185MHz (typ.)
• Low Power Dissipation
High Noise Immunity
at Vcc=5V
Icc= 4A(Max.) at Ta = 25°C
•VNIH=VNIL = 28% Vcc (Min.)
Power Down Protection is provided on all inputs.
Balanced Propagation Delays... tpLH=tpHL
• Wide Operating Voltage Range. Vcc (opr)-2V-5.5V
Low Noise -
VOLP=0.8V (Max.)
• Pin and Function Compatible with 74ALS161/163