Texas Instruments 74AVC8T245RHLRG4

Overview

74AVC8T245RHLRG4 from Texas Instruments is an 8-bit dual-supply bus transceiver enabling bidirectional voltage-level translation between 1.2 V–3.6 V domains, with configurable A/B port supplies (VCCA/VCCB), 3-state outputs, and direction control via DIR input. It supports up to 320 Mbps data rate at ≥1.8 V supplies and operates across –40°C to +125°C for industrial and telecom interconnects.

For engineers reviewing the 74AVC8T245RHLRG4 datasheet, 74AVC8T245RHLRG4 pinout, 74AVC8T245RHLRG4 application, or 74AVC8T245RHLRG4 equivalent, key selection criteria include dual-rail supply flexibility, Ioff partial-power-down support, VCC isolation behavior, 4.6-V I/O tolerance, and VQFN-24 (RHL) package thermal performance (RθJA = 36.8°C/W).

Technical Context

The 74AVC8T245RHLRG4 implements a fully asynchronous, noninverting transceiver architecture with independent A-port (VCCA-referenced) and B-port (VCCB-referenced) power rails. Control inputs DIR and OE are referenced solely to VCCA, ensuring consistent logic thresholds regardless of VCCB level.

Its dual-rail design enables true bidirectional translation-e.g., A port at 1.8 V driving B port at 3.3 V, or vice versa-with propagation delays as low as 2.3 ns (A→B, VCCA=3.3 V, VCCB=1.2 V) and output enable/disable times down to 1.7 ns (tPHZ, OE→A, VCCA=3.3 V). The VCC isolation feature forces both ports into high-impedance when either VCCA or VCCB = GND.

Key Specifications

Pinout & Package

74AVC8T245RHLRG4 uses a 24-pin VQFN package (RHL) with 5.5 mm × 3.5 mm footprint and wettable flank leads for automated optical inspection. Thermal resistance RθJA = 36.8°C/W enables high-density routing without forced air cooling.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar bus transceiver applications.

Compared with SN74AVCH8T245RHLRG4, the 74AVC8T245RHLRG4 lacks bus-hold but offers identical timing and drive; versus TXB0108RGER, it provides deterministic DIR control and higher drive for timing-critical buses, at the cost of one additional control pin and slightly better thermal performance.

Availability

74AVC8T245RHLRG4 is available at Aetrix Electronics and suitable for industrial PLC backplanes, automotive ADAS sensor hubs, and telecom baseband processor interfaces requiring stable component supply, long-term lifecycle support, and traceable sourcing.

Supply support for 74AVC8T245RHLRG4 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Texas Instruments is a global semiconductor leader delivering analog, embedded processing, and connectivity solutions for industrial, automotive, and communications markets.

The SN74AVC family targets low-voltage, high-speed bidirectional bus translation in space-constrained systems, emphasizing power efficiency, wide supply flexibility, and robust ESD performance.

FAQ

What voltage ranges can 74AVC8T245RHLRG4 support on its A and B ports?

The 74AVC8T245RHLRG4 supports independent supply voltages from 1.2 V to 3.6 V on both VCCA (A port) and VCCB (B port), enabling translation between any combination of 1.2 V, 1.5 V, 1.8 V, 2.5 V, and 3.3 V logic domains. The device remains fully operational even when VCCA or VCCB is as low as 1.2 V, and I/Os tolerate up to 4.6 V regardless of supply level. This makes 74AVC8T245RHLRG4 ideal for mixed-voltage system integration.

How does the VCC isolation feature work in 74AVC8T245RHLRG4?

In the 74AVC8T245RHLRG4, if either VCCA or VCCB is driven to GND while the other supply remains active, all I/Os on both A and B ports automatically enter a high-impedance state. This prevents bus contention and back-current flow during asymmetric power sequencing-common in hot-plug or modular systems. The behavior is intrinsic to the silicon design and requires no external circuitry, making 74AVC8T245RHLRG4 suitable for robust power-management architectures.

Can 74AVC8T245RHLRG4 operate with different supply voltages on VCCA and VCCB simultaneously?

Yes, the 74AVC8T245RHLRG4 is explicitly designed for simultaneous dual-supply operation with different voltages on VCCA and VCCB-for example, VCCA = 1.8 V and VCCB = 3.3 V. Its internal level-shifting circuitry ensures correct logic interpretation and output drive on each side, with control inputs (DIR, OE) referenced strictly to VCCA. This capability is validated across the full operating temperature range (–40°C to +125°C) and forms the core value proposition of the 74AVC8T245RHLRG4.

What is the maximum data rate supported by 74AVC8T245RHLRG4, and under what conditions?

The 74AVC8T245RHLRG4 supports a maximum data rate of 320 Mbps when both VCCA and VCCB are ≥1.8 V. At lower supplies (e.g., VCCA < 1.8 V or VCCB < 1.8 V), the rated maximum drops to 170 Mbps. These values reflect guaranteed timing performance under worst-case process/voltage/temperature corners and are derived from measured tPLH/tPHL propagation delays as low as 2.3 ns. The 74AVC8T245RHLRG4 maintains this performance across its full industrial temperature range.

Does 74AVC8T245RHLRG4 support partial power-down, and how is it implemented?

Yes, the 74AVC8T245RHLRG4 supports partial power-down via its Ioff feature. When either VCCA or VCCB is at 0 V, the Ioff circuitry disables all I/O outputs, limiting leakage current to ±5 μA maximum per pin. This prevents damaging back-current from active buses into a powered-down transceiver-a critical requirement for hot-swap, power-gated subsystems, and energy-efficient designs. The 74AVC8T245RHLRG4's Ioff behavior is specified and tested per JESD78 Class II latch-up standards.