Texas Instruments SN74AVC4T245PW

Overview

SN74AVC4T245 from Texas Instruments is a 4-bit dual-supply noninverting bus transceiver enabling bidirectional voltage-level translation between 1.2V, 1.5V, 1.8V, 2.5V, and 3.3V domains. It features independent VCCA (1.2–3.6V) and VCCB (1.2–3.6V) rails, 4.6V I/O tolerance, Ioff partial-power-down support, and up to 380Mbps data rate (1.8V→3.3V). It serves in mixed-voltage system interconnects such as SoC-to-peripheral interfaces.

For engineers reviewing the SN74AVC4T245 datasheet, SN74AVC4T245 pinout, SN74AVC4T245 application, or SN74AVC4T245 equivalent, key selection considerations include dual-rail configurability, direction-control logic per channel, 3-state output enable timing, and thermal performance in TSSOP-16 packaging for space-constrained PCB layouts.

Technical Context

The SN74AVC4T245 implements two independent 2-bit bidirectional channels, each with dedicated DIR and OE controls referenced to VCCA. Its fully configurable dual-rail architecture decouples A-port (VCCA-referenced) and B-port (VCCB-referenced) logic thresholds, enabling asynchronous translation without clocking or protocol awareness.

Each channel operates in three functional states: A→B (DIR=H, OE=L), B→A (DIR=L, OE=L), or high-impedance isolation (OE=H). The Ioff circuit disables outputs when either VCCA or VCCB is at GND, preventing backflow current during partial power-down - critical for hot-swap and low-power sequencing.

Key Specifications

Pinout & Package

TSSOP-16 package (PW), 5mm × 6.4mm body, 0.65mm pitch, exposed thermal pad (not electrically connected).

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LVC4T245PW and TXS0104EPW, the SN74AVC4T245 uniquely supports 1.2V operation, delivers 380Mbps throughput, and provides explicit DIR control - making it the only option for high-speed, ultra-low-voltage, deterministically bidirectional translation in modern SoC interconnects.

Availability

SN74AVC4T245 is available at Aetrix Electronics and suitable for industrial PLC I/O expansion, automotive ADAS sensor hubs, enterprise SSD controllers, and telecom baseband FPGA bridges requiring stable component supply across extended temperature and mixed-voltage environments.

Supply support for SN74AVC4T245 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 company delivering analog and embedded processing solutions for industrial, automotive, personal electronics, and enterprise applications.

The SN74AVC4T245 belongs to TI's AVC (Advanced Very-Low-Voltage CMOS) logic family, engineered specifically for high-speed, low-voltage bidirectional translation in next-generation mixed-signal systems with stringent power and timing constraints.

FAQ

What voltage ranges does the SN74AVC4T245 support on its A and B ports?

The SN74AVC4T245 supports independent 1.2V to 3.6V operation on both VCCA (A port) and VCCB (B port), enabling translation between any combination of 1.2V, 1.5V, 1.8V, 2.5V, and 3.3V logic domains. This full-range dual-rail capability is confirmed in Section 7.3.1 of the datasheet and verified by recommended operating conditions in Section 5.3.

How does the SN74AVC4T245 handle power sequencing when one supply is ramped before the other?

The SN74AVC4T245 incorporates VCC isolation: if either VCCA or VCCB is at GND, both A and B ports automatically enter high-impedance state. This prevents signal contention or backfeed during asymmetric power-up/down sequences - a feature explicitly documented in Section 7.1 and Section 7.4 of the datasheet.

Can the SN74AVC4T245 be used for unidirectional translation only?

Yes. The SN74AVC4T245 supports unidirectional operation by holding one DIR input constant (e.g., 1DIR = H for A→B only) while using OE to gate output enables. Its per-channel DIR/OE architecture allows flexible configuration - confirmed in Table 7-1 (Function Table) and Section 7.4 of the datasheet.

What is the maximum data rate achievable with the SN74AVC4T245, and under what conditions?

The SN74AVC4T245 achieves up to 380Mbps when translating from 1.8V to 3.3V, as specified in Section 1 Features and validated in Section 5.7–5.11 switching characteristics. Performance degrades at lower voltage combinations (e.g., 150Mbps for 1.5V→1.2V), with exact values dependent on VCCA/VCCB pairing and load conditions.

Does the SN74AVC4T245 require external pull-up resistors on control pins?

OE should be tied to VCCA via a pull-up resistor during power-up/down to ensure high-impedance state until supplies stabilize - per Section 8.3. DIR pins have no internal pull-up; external biasing is required if left undriven. Resistor value depends on driver sink capability, with typical values ranging from 4.7kΩ to 10kΩ.