74F899QC

Overview

The Fairchild Semiconductor 74F899QC is a 9-bit to 9-bit parity transceiver equipped with transparent latches. It operates as a feed-through transceiver or generates and checks parity for 8-bit data buses in either direction. The device features independent latch enables for A-to-B and B-to-A directions, an ODD/EVEN parity select pin, and separate ERRA and ERRB output pins for error detection. It supports 3-state outputs and is housed in a 28-pin PLCC package.

Feature Summary

• Transparent latchable transceiver architecture supporting bidirectional data flow
• Integrated parity generation and checking capabilities for 8-bit data buses
• Independent latch enable controls for distinct A-to-B and B-to-A operational directions
• Separate error signal output pins dedicated to parity verification

Applications

• System applications requiring parity checking on 8-bit data busses
• Replacement for legacy devices such as the 280, 657, and 373
• Data transmission systems utilizing transparent latching mechanisms

Procurement Notes

Verify component authenticity through authorized distributors or manufacturer channels. Confirm RoHS compliance status and specific package variant details against official datasheets. Ensure supply chain integrity by sourcing from verified partners to avoid counterfeit components. Review technical specifications for voltage levels and operating temperature ranges prior to integration.

Selection Notes

Select this component for designs requiring 9-bit parity transceivers with transparent latching. It serves as a direct functional replacement for older parity checker models like the 74280 and 74657 without necessitating changes to tri-state logic configurations. Evaluate package compatibility with existing PCB footprints, specifically the 28-PLCC form factor, before finalizing the design.

Part Context

The 74F899 belongs to the standard 74-series logic family, specifically designed for high-speed digital applications. As a parity transceiver, it addresses data integrity needs in bus-oriented systems. The QC suffix typically denotes a plastic leaded chip carrier package variant within the Fairchild product line, distinguishing it from other packaging options like SOIC or SSOP.

Replacement Considerations

The 74F899 may replace the 74280, 74657, and 74373 in system applications. Verify that the target application does not require specific timing characteristics unique to those legacy parts. Ensure that the 3-state output behavior aligns with the existing bus architecture requirements.