74HC299D,653

Shift Registers Overview

The Nexperia 74HC299D,653 is an 8-bit universal shift register with 3-state outputs housed in a 20-lead SO plastic small outline package (SOT163-1). It contains eight edge-triggered D-type flip-flops and supports synchronous shift-right, shift-left, parallel load, and hold operations. The device operates on a supply voltage of 2.0 V to 6.0 V and functions within an ambient temperature range of -40 °C to +125 °C.

Shift Registers Feature Summary

• Multiplexed I/O pins provide improved bit density by serving as both data inputs and 3-state outputs.
• Four operating modes including shift left, shift right, hold, and parallel load controlled by mode select inputs.
• Asynchronous master reset input overrides clock and mode signals to force all flip-flops low.

Shift Registers Applications

• Bus driver applications requiring tri-state output control
• Serial-to-parallel and parallel-to-serial data conversion circuits
• Expansion of word lengths through cascading serial outputs

Shift Registers Procurement Notes

Verify the specific ordering suffix matches the required package variant. Confirm that the component meets RoHS3 compliance standards for your manufacturing process. Ensure the selected supplier provides traceability documentation consistent with Nexperia's product specifications.

Shift Registers Selection Notes

Select this component when an 8-bit universal shift register with multiplexed I/O functionality is required. The 3-state outputs allow direct connection to bus lines. Verify that the logic family voltage levels align with the system design requirements.

Shift Registers Part Context

This part belongs to the 74HC series of high-speed CMOS logic devices manufactured by Nexperia. It is functionally compatible with other industry-standard 8-bit universal shift registers but offers specific pinout and electrical characteristics defined by the manufacturer.

Shift Registers Replacement Considerations

Check datasheets for alternative manufacturers to ensure pin compatibility and electrical parameter alignment before substitution.

Shift Registers FAQ

How are the I/O pins configured?

The I/O pins serve as parallel data inputs during the load operation and as 3-state outputs during shift or hold operations.

What controls the shift direction?

The shift direction is determined by the state of the mode select inputs S0 and S1 combined with the serial data inputs DSL and DSR.