74LCXHR162245TTR

Overview

The 74LCXHR162245TTR is a low voltage CMOS 16-bit bus transceiver with 3-state outputs, manufactured by STMicroelectronics. It utilizes sub-micron silicon gate and double-layer metal wiring C²MOS technology. The device supports an operating voltage range of 2.0V to 3.6V, with data retention at 1.5V. It features 5V tolerant inputs and outputs, ensuring compatibility with 5V signal environments. Key electrical parameters include a maximum propagation delay of 4.7 ns at VCC = 3V, symmetrical output impedance with |IOH| = IOL = 12 mA (min) at VCC = 3V, and latch-up performance exceeding 500 mA per JESD 17 standards.

Feature Summary

• Provides two-way asynchronous communication between data buses with directional control via DIR input and isolation via enable inputs nG.
• Features 5V tolerant inputs and outputs, allowing safe interfacing with 5V signal environments while operating at lower voltages.
• Includes bus hold on both sides to eliminate the need for external pull-up or pull-down resistors on floating data inputs.
• Outputs incorporate 26 Ω series resistors designed to reduce overshoot and undershoot in high-speed applications.

Applications

• Low power and high speed 3.3V applications requiring bus buffering.
• Interfaces connecting data buses between components operating at different voltage levels.
• Systems requiring PCI bus level guarantees at specified current loads.

Procurement Notes

Verify component authenticity through authorized distributors or direct manufacturer channels. Confirm package integrity upon receipt, as the TSSOP-48 form factor requires careful handling during soldering. Check datasheet revisions for any updates to absolute maximum ratings or recommended operating conditions before finalizing design integration.

Selection Notes

Select this component when designing systems that require bidirectional data transfer between buses with mixed voltage domains. Ensure the application operates within the 2.0V to 3.6V supply range. Consider the 5V tolerance feature if interfacing directly with legacy 5V logic without additional level shifting circuitry.

Part Context

This part belongs to the 74LCX family of low voltage CMOS logic devices from STMicroelectronics. It is functionally compatible with the 74 series 16245 standard. The device is classified as obsolete by the manufacturer, indicating it may no longer be actively produced or supported for new designs.

Replacement Considerations

Check for active equivalents in the 74LVC or 74LVCR families from other manufacturers such as Texas Instruments or Nexperia. Verify pinout compatibility and electrical specifications against the original requirements before substitution.

FAQ

What is the purpose of the 26 Ω resistors in the outputs?

The 26 Ω resistors are included in the output design to reduce overshoot and undershoot, which helps minimize line noise in high-speed applications.

How does the device handle floating data inputs?

Bus hold is provided on both sides of the transceiver to eliminate the need for external pull-up or pull-down resistors, effectively managing floating data inputs.