74ABT899CQC

Overview

The Fairchild Semiconductor 74ABT899CQC is a 9-bit latchable transceiver with parity generator and checker. It operates within a supply voltage range of 4.5V to 5.5V and features transparent latches for data storage. The device supports bidirectional data transfer between A and B buses, offering independent latch enables for each direction. It provides high drive capability with 64 mA output sink current and includes ODD/EVEN selection pins for flexible parity configuration.

Feature Summary

• Supports simultaneous parity generation and checking across two directions
• Features independent latch enable controls for A-B and B-A data paths
• Provides selectable odd or even parity modes via dedicated control pin
• Ensures glitch-free bus loading during power-up and power-down cycles

Applications

• High-speed data bus systems requiring error detection
• Memory interface circuits with parity verification
• Communication protocols demanding data integrity checks

Procurement Notes

Verify the specific suffix CQC corresponds to the PLCC package variant when sourcing. Confirm manufacturer origin as Fairchild Semiconductor or authorized successor entities like NXP. Ensure RoHS compliance status matches project requirements. Check for obsolete status indicators if sourcing from secondary markets. Validate datasheet revisions for accurate electrical specifications.

Selection Notes

Select this component for applications requiring integrated parity logic alongside data buffering. The 28-pin PLCC package suits prototyping or legacy board designs. Consider the 64 mA drive strength for heavy bus loads. Verify compatibility with 5V logic families. Evaluate thermal performance for enclosed environments due to CMOS power dissipation characteristics.

Part Context

This part belongs to the 74ABT series of advanced BiCMOS logic devices. It replaces older parity generators like the 543 or 280 without requiring additional transceivers. The ABT technology offers speed comparable to ALS logic with CMOS low power consumption. It integrates functions previously handled by multiple discrete components.

Replacement Considerations

Direct substitutes include the 74ABT899D in SOIC packages. Cross-reference with NXP 935064030112 for equivalent functionality. Verify pinout compatibility before swapping with similar parity transceivers.