SN74GTL16616DGGR

Overview

The SN74GTL16616DGGR is a 17-bit Universal Bus Transceiver (UBT) from the Widebus family, translating between LVTTL and GTL/GTL+ signal levels. It operates with VCC(3.3V) for LVTTL buffers and VCC(5V) for internal/GTL circuitry. The device supports mixed-mode operation on the A-port and control inputs, featuring buffered clock outputs (CLKOUT/CLKIN). It provides transparent, latched, clocked, or clock-enabled data transfer modes. Operating temperature range is -40°C to +85°C.

Feature Summary

• Combines D-type latches and flip-flops for flexible data transfer modes including transparent, latched, clocked, and clock-enabled operations.
• Integrates OEC circuitry to improve signal integrity and reduce electromagnetic interference during high-speed switching.
• Includes active bus-hold circuitry on data inputs to maintain valid logic states without external pullup or pulldown resistors.
• Supports partial-power-down mode via Ioff circuitry to prevent damaging backflow current when powered down.

Applications

• Interface between cards operating at LVTTL logic levels and backplanes operating at GTL/GTL+ signal levels.
• Mixed-mode system designs requiring translation between 3.3V and 5V signal domains.
• High-speed data transfer applications utilizing buffered clock outputs for synchronization.

Procurement Notes

Verify the specific ordering suffix DGGR corresponds to the TSSOP-56 tape and reel package configuration. Confirm that the design accommodates the dual supply voltage requirements of 3.3V and 5V as specified in the recommended operating conditions. Ensure proper termination voltages (VTT) and reference voltages (VREF) are established for the intended GTL or GTL+ signal level operation.

Selection Notes

Select this component when a 17-bit transceiver is required to bridge LVTTL and GTL/GTL+ domains with flexible timing control. The UBT architecture allows for complex data handling modes beyond simple buffering. Consider the distributed VCC and GND pins for noise minimization in high-speed switching environments. Verify compatibility with existing clock distribution networks due to the dedicated CLKOUT and CLKIN functions.

Part Context

This device belongs to Texas Instruments' Widebus family, designed for high-performance bus interfacing. It serves as an equivalent to the '16601 function but with enhanced GTL/GTL+ support. The SN74GTL16616 series addresses the need for reliable data translation in mixed-voltage systems, providing robust ESD protection and latch-up performance exceeding standard class II ratings.

Replacement Considerations

SN74GTL16616DL

FAQ

How does the device handle unused or undriven LVTTL inputs?

Active bus-hold circuitry holds unused or undriven LVTTL inputs at a valid logic state, eliminating the need for external pullup or pulldown resistors.

What is the purpose of the CLKOUT pin?

The CLKOUT pin provides a copy of the CLKAB signal at GTL/GTL+ signal levels, allowing for buffered clock distribution within the GTL domain.