1 Features
• Buffered inputs
• Asynchronous reset
• Typical fMAX = 60MHz at VCC = 5V, CL = 15pF,
TA = 25°C
• Fanout (overtemperature range)
– Standard Outputs: 10 LSTTL loads
– Bus driver outputs: 15 LSTTL loads
• Wide operating temp range: – 55°C to 125°C
• Balanced propagation delay and transition times
• Significant power reduction compared to LSTTL
logic ICs
• HC types
– 2V to 6V operation
– High noise immunity: NIL = 30%, NIH = 30% of
VCC at VCC = 5V
• HCT types
– 4.5V to 5.5V operation
– Direct LSTTL input logic compatibility, VIL =
0.8V (Max), VIH = 2V (Min)
– CMOS input compatibility, II ≤ 1μA at VOL, VOH

2 Description
The ’HC164 and ’HCT164 are 8-bit, serial-in, parallelout,
shift registers with asynchronous reset. Data is
shifted on the positive edge of Clock (CLK). A LOW
on the RESET (CLR) pin resets the shift register and
all outputs go to the LOW state regardless of the
input conditions. Two Serial Data inputs (A and B) are
provided, either one can be used as a data enable
control.