Texas Instruments SN74AVC4T245PW-P

Overview

SN74AVC4T245PW-P from Texas Instruments is a 4-bit dual-supply noninverting bus transceiver enabling bidirectional voltage translation between 1.2V, 1.5V, 1.8V, 2.5V, and 3.3V logic 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 interconnects between processors and peripherals in portable electronics.

For engineers reviewing the SN74AVC4T245PW-P datasheet, SN74AVC4T245PW-P pinout, SN74AVC4T245PW-P application, or SN74AVC4T245PW-P equivalent, key selection criteria include dual-rail configurability, 3-state output control per channel, Ioff-enabled isolation during power sequencing, thermal performance in TSSOP-16, and verified 380Mbps translation capability at 1.8V-to-3.3V.

Technical Context

The SN74AVC4T245PW-P implements two independent 2-bit bidirectional channels, each with dedicated DIR and OE controls referenced to VCCA. Its dual-rail architecture decouples A-port (VCCA-referenced) and B-port (VCCB-referenced) logic levels, enabling asynchronous translation without clocking or direction latching.

Each channel supports independent enable/disable via OE and direction control via DIR, with functional modes defined by OE/DIR combinations: A→B (OE=L, DIR=H), B→A (OE=L, DIR=L), or high-impedance isolation (OE=H). Ioff circuitry disables outputs when either VCCA or VCCB = 0V, preventing backflow current during partial power-down.

Key Specifications

Pinout & Package

PW package is a 16-pin Thin Shrink Small Outline Package (TSSOP) measuring 5mm × 6.4mm, with gull-wing leads and 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 TXB0104PWR, the SN74AVC4T245PW-P delivers broader voltage support (1.2–3.6V), higher speed (380Mbps), and Ioff-enabled power sequencing - making it optimal for mixed-voltage SoC interconnects requiring deterministic control and industrial reliability.

Availability

SN74AVC4T245PW-P is available at Aetrix Electronics and suitable for mobile processor interconnect, industrial sensor hub, enterprise SSD controller interface, and telecom baseband FPGA link applications requiring stable component supply, long-term lifecycle assurance, and traceable sourcing.

Supply support for SN74AVC4T245PW-P 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 communications markets.

The SN74AVC4T245PW-P belongs to TI's AVC (Advanced Very-Low-Voltage CMOS) logic family, engineered specifically for high-speed, low-voltage bidirectional translation in power-sensitive, mixed-rail digital systems.

FAQ

What is the minimum operating voltage for SN74AVC4T245PW-P on both VCCA and VCCB rails?

The SN74AVC4T245PW-P operates down to 1.2V on both VCCA and VCCB rails. This enables compatibility with modern ultra-low-voltage processors and memory interfaces. Operation below 1.2V is not specified and may result in unreliable logic thresholds or increased propagation delay. The device remains fully functional across the entire 1.2V–3.6V range for either rail independently.

Does SN74AVC4T245PW-P support automatic direction sensing like auto-bidirectional translators?

No, SN74AVC4T245PW-P does not support automatic direction sensing. It requires explicit control of the DIR pin for each channel to determine data flow direction (A→B or B→A). This deterministic control eliminates timing uncertainty and bus contention risks present in auto-sensing devices, making SN74AVC4T245PW-P suitable for synchronous protocols such as SPI, I²C buffer extensions, and memory-mapped peripheral interfaces.

How does the Ioff feature function in SN74AVC4T245PW-P during power sequencing?

In SN74AVC4T245PW-P, the Ioff circuitry actively disables all I/O outputs when either VCCA or VCCB is at 0V, limiting leakage current to ±1μA maximum. This prevents backflow current from a live rail into a powered-down domain - a critical requirement for hot-plug, partial-power-down, and staggered power-up sequences in modular systems. The feature is intrinsic and requires no external circuitry.

Can SN74AVC4T245PW-P translate between 1.2V and 3.3V, and what is its maximum data rate in that configuration?

Yes, SN74AVC4T245PW-P supports 1.2V ↔ 3.3V translation. In the 1.2V-to-3.3V direction, its maximum data rate is 100Mbps. This is specified in the datasheet's switching characteristics tables under VCCA = 1.2V conditions. Performance is limited by reduced noise margin and slower edge rates at the lowest VCCA, but remains fully functional and characterized for reliable operation.

Is the thermal pad on the PW package of SN74AVC4T245PW-P electrically connected or intended for grounding?

The thermal pad on the SN74AVC4T245PW-P's PW (TSSOP-16) package is not electrically connected to any internal node - it is a mechanical thermal relief structure only. TI documentation confirms it is "not connected" and recommends leaving it floating or connecting it to GND solely for thermal conduction, not electrical functionality. No electrical performance benefit or risk arises from its connection state.