Features
• Asynchronous Master Reset
• J, K, (D) Inputs to First Stage
• Fully Synchronous Serial or Parallel Data Transfer
• Shift Right and Parallel Load Capability
• Complementary Output From Last Stage
• Buffered Inputs
• Typical fMAX = 50MHz at VCC = 5V,
CL = 15pF, TA = 25oC
• Fanout (Over Temperature Range)
- Standard Outputs . . . . . . . . . . . . . . . 10 LSTTL Loads
- Bus Driver Outputs . . . . . . . . . . . . . 15 LSTTL Loads
• Wide Operating Temperature Range . . . -55oC to 125oC
• 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

Description
The device is useful in a wide variety of shifting, counting
and storage applications. It performs serial, parallel, serial to
parallel, or parallel to serial data transfers at very high
speeds.
The two modes of operation, shift right (Q0-Q1) and parallel
load, are controlled by the state of the Parallel Enable (PE)
input. Serial data enters the first flip-flop (Q0) via the J and K
inputs when the PE input is high, and is shifted one bit in the
direction Q0-Q1-Q2-Q3 following each Low to High clock
transition. The J and K inputs provide the flexibility of the JKtype
input for special applications and by tying the two pins
together, the simple D-type input for general applications.
The device appears as four common-clocked D flip-flops
when the PE input is Low. After the Low to High clock
transition, data on the parallel inputs (D0-D3) is transferred
to the respective Q0-Q3 outputs. Shift left operation (Q3-Q2)
can be achieved by tying the Qn outputs to the Dn-1 inputs
and holding the PE input low.
All parallel and serial data transfers are synchronous, occurring
after each Low to High clock transition. The ’HC195 series
utilizes edge triggering; therefore, there is no restriction on the
activity of the J, K, Pn and PE inputs for logic operations, other
than set-up and hold time requirements. A Low on the
asynchronous Master Reset (MR) input sets all Q outputs Low,
independent of any other input condition.