Texas Instruments SN74AXC4T245QPWRQ1

Overview

SN74AXC4T245 from Texas Instruments is a four-bit noninverting bus transceiver with dual configurable voltage rails (VCCA and VCCB), supporting 0.65V–3.6V operation per port, ±8000V HBM ESD rating, –40°C to +125°C temperature range, and up to 380Mbps data rate in 1.8V-to-3.3V translation. It enables bidirectional level shifting in automotive infotainment domain controllers interfacing low-voltage MCUs with legacy 3.3V peripherals.

For engineers reviewing the SN74AXC4T245 datasheet, SN74AXC4T245 pinout, SN74AXC4T245 application, or SN74AXC4T245 equivalent, key selection criteria include independent A/B port voltage configuration, VCC isolation behavior below 100mV, Ioff partial-power-down support, glitch-free power sequencing, and dual direction-control inputs enabling simultaneous up/down translation paths.

Technical Context

The SN74AXC4T245 implements asynchronous bidirectional data flow using two independent transceiver pairs (1A↔1B and 2A↔2B), each controlled by dedicated DIR and OE pins referenced solely to VCCA. Its dual-rail architecture allows A-port I/Os to track VCCA (0.65V–3.6V) and B-port I/Os to track VCCB (0.65V–3.6V), enabling true voltage-domain isolation.

VCC isolation disables all outputs when either VCCA or VCCB falls below 100mV, while Ioff circuitry limits leakage current to ±4µA at 0V bias during partial power-down. Glitch-free sequencing permits arbitrary power-up/power-down order of VCCA and VCCB without bus contention or latch-up risk.

Key Specifications

Pinout & Package

Packaged in 16-pin TSSOP (PW), WQFN (BQB), or UQFN (RSV); all variants share identical pin numbering and function mapping per TI SCES877B Rev. April 2024.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LXC4T245PWR and TXS0104EPWR, the SN74AXC4T245 provides guaranteed operation at +125°C, robust VCC isolation for fail-safe bus management, and higher ESD tolerance - making it the sole choice for automotive gateway and mission-critical industrial control interfaces.

Availability

SN74AXC4T245 is available at Aetrix Electronics and suitable for automotive infotainment gateways, industrial PLC backplanes, and wireless baseband processor interfaces requiring stable component supply across extended temperature and long product lifecycles.

Supply support for SN74AXC4T245 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 specializing in analog and embedded processing solutions, with leadership in automotive, industrial, and communications markets.

The AXC family targets high-speed, low-voltage bidirectional level translation for next-generation processors and FPGAs, emphasizing robustness in harsh environments and seamless integration into mixed-supply systems.

FAQ

What is the minimum operating voltage for SN74AXC4T245 on each supply rail?

The SN74AXC4T245 supports VCCA and VCCB down to 0.65V independently. This enables direct interfacing with advanced low-power cores such as ARM Cortex-M33 or RISC-V processors operating at sub-1V supply levels, while maintaining full functionality and specified timing performance.

How does SN74AXC4T245 handle power sequencing between VCCA and VCCB?

The SN74AXC4T245 features glitch-free power supply sequencing: either VCCA or VCCB may be powered on or off in any order without causing bus contention, output glitches, or latch-up. This eliminates the need for complex power-rail supervisors or sequencing ICs in multi-rail systems.

Can SN74AXC4T245 operate with only one supply rail powered?

Yes - the SN74AXC4T245 supports partial-power-down mode via its Ioff protection circuitry. When either VCCA or VCCB is at 0V, leakage current is limited to ±4µA, preventing back-current flow and enabling safe operation with one rail unpowered while the other remains active.

What is the purpose of the VCC isolation feature in SN74AXC4T245?

The VCC isolation feature in SN74AXC4T245 disables all I/O outputs and forces them into high-impedance state whenever either VCCA or VCCB drops below 100mV. This prevents unintended signal driving during brown-out conditions, protecting downstream devices and ensuring system-level fault containment.

Does SN74AXC4T245 require external pull-up or pull-down resistors on control pins?

Yes - to ensure defined logic states during power-up, TI recommends pulling 1OE and 2OE high to VCCA via external resistors (typically 10kΩ). This guarantees all outputs start in high-impedance mode, avoiding bus conflicts before firmware initializes direction and enable controls.