DS8922AM

Overview

The DS8922AM is a dual differential line driver and receiver pair designed for RS-422, ST506, ST412, and ESDI standards. It operates on a single 4.5V to 5.5V supply with a typical propagation delay of 12ns and output skew of ±0.5ns. The device features TRI-STATE outputs controlled by independent enable inputs, complementary driver outputs, and an input fail-safe circuit that defaults the receiver output to a logical one state when inputs are open. It includes glitch-free power-up/down circuitry and supports TTL/CMOS logic levels.

Feature Summary

• Dual differential line driver and receiver pairs meeting RS-422 and disk drive interface standards
• TRI-STATE outputs with independent control functions for drivers and receivers
• Input fail-safe circuitry ensures logical one state upon open receiver inputs
• Glitch-free power-up/down circuitry prevents erroneous transmission during system transitions

Applications

• ESDI (Enhanced Small Device Interface) disk drive applications
• ST504 and ST412 disk drive interfaces
• RS-422 communication systems requiring differential signaling

Procurement Notes

Verify the specific ordering suffix against the current Texas Instruments Package Option Addendum. The 'AM' designation corresponds to the SOIC package variant. Confirm the production status, as this component may be listed under LIFEBUY or OBSOLETE categories in official TI documentation. Ensure compatibility with required operating temperature ranges and packaging quantities before finalizing procurement plans.

Selection Notes

Select the DS8922AM for applications requiring dual differential channels with TRI-STATE capability. Verify that the 4.5V to 5.5V supply voltage range aligns with the system design. Consider the 70mV typical hysteresis for noise margin requirements. Ensure the SOIC package dimensions fit the PCB layout constraints. Check if separate driver and receiver enables are necessary, as this model shares common control for the pair.

Part Context

The DS8922AM belongs to the DS8922/DS8922A/DS8923A family of TRI-STATE RS-422 dual differential line drivers and receivers. This series was originally developed by National Semiconductor and is now manufactured by Texas Instruments. The family provides solutions for high-speed data transmission in legacy and industrial disk drive interfaces.

Replacement Considerations

Check the Texas Instruments Product Folder for currently recommended replacements if the DS8922AM is discontinued. Verify pinout compatibility and electrical characteristics against alternative RS-422 transceivers such as the DS89C21 or similar TRI-STATE differential drivers.