SN74AS821ADW

Flip Flops Overview

The SN74AS821ADW is a single 10-bit bus-interface flip-flop from the AS logic series, manufactured by Texas Instruments. It features non-inverting D-type inputs and three-state outputs in a 24-pin SOIC package. The device operates within a supply voltage range of 4.5 V to 5.5 V and supports TTL input levels. Key electrical characteristics include a propagation delay of 13 ns at 5 V with a 50 pF load, a high-level output current of -24 mA, and a low-level output current of 48 mA. It functions as a positive-edge-triggered register suitable for high-speed data buffering.

Flip Flops Feature Summary

• Provides 10-bit parallel data storage with bus interface capability
• Features three-state outputs for direct system bus connection
• Utilizes advanced Schottky (AS) technology for high-speed operation
• Accepts TTL-compatible input signals

Flip Flops Applications

• High-speed data buffering between microprocessors and memory systems
• Parallel-to-serial conversion interfaces
• Bus isolation in computer architecture designs
• Register stages in digital signal processing circuits

Flip Flops Procurement Notes

Verify the specific suffix 'DW' confirms the 24-SOIC package and industrial temperature range if required. Confirm RoHS compliance status through official manufacturer documentation or authorized distributors, as legacy AS series parts may have varying environmental declarations. Ensure the source provides valid traceability for this discontinued or legacy component type.

Flip Flops Selection Notes

Select this component when a 10-bit wide register with high-speed performance is required. The AS series offers faster switching speeds compared to standard LS or ALS families. Ensure the design accommodates the 5V-only supply requirement and that the load capacitance does not exceed specifications to maintain the 13 ns propagation delay. Verify pin compatibility with existing PCB footprints.

Flip Flops Part Context

This part belongs to the SN74AS821A family of 10-bit bus-interface flip-flops. It is functionally similar to the SN74S821 but with improved speed characteristics due to Advanced Schottky technology. The 'D' indicates the die revision, and 'W' denotes the plastic small-outline package. It serves as a bridge between fast processor buses and slower peripheral devices.

Flip Flops Replacement Considerations

The SN74AS821ADWR is the reel version of this component. Cross-reference with SN74LS821 for lower speed requirements, though pinouts and logic functions remain compatible. Verify that any substitute meets the 5V supply and 3-state output requirements.