Shift Register Single 8-Bit Serial/Parallel to Serial/Parallel 20-Pin SO T/R

The 74HC299; 74HCT299 are high-speed Si-gate CMOS devices which are pin-compatible with Low-power Schottky TTL (LSTTL) devices. They are specified in compliance with JEDEC standard no. 7A. The 74HC299; 74HCT299 contain eight edge-triggered D-type flip-flops and the interstage logic necessary to perform synchronous shift-right, shift-left, parallel load and hold operations. An operation is determined by the mode select inputs S0 and S1. Pins I/O0 to I/O7 are flip-flop 3-state buffer outputs which allow them to operate as data inputs in parallel load mode. The serial outputs Q0 and Q7 are used for expansion in serial shifting of longer words. A LOW signal on the asynchronous master reset input overrides the Sn and clock CP inputs and resets the flip-flops. All other state changes are initiated by the rising edge of the clock pulse. Inputs can change when the clock is in either state, provided that the recommended set-up and hold times are observed.

• Multiplexed inputs/outputs provide improved bit density
• Four operating modes:
  • Shift left
  • Shift right
  • Hold (store)
  • Load data
• Operates with output enable or at high-impedance OFF-state (Z)
• 3-state outputs drive bus lines directly
• Cascadable for n-bit word lengths
• ESD protection:
  • HBM JESD22-A114E exceeds 2000 V
  • MM JESD22-A115-A exceeds 200 V
• Specified from -40 °C to +85 °C and from -40 °C to +125 °C