Texas Instruments SN74AVCH8T245PWG4

Overview

SN74AVCH8T245PWG4 from Texas Instruments is an 8-bit dual-supply noninverting bus transceiver enabling bidirectional voltage translation between 1.2V–3.6V domains (e.g., 1.8V ↔ 3.3V), with configurable level-shifting, 3-state outputs, bus-hold circuitry, and Ioff partial-power-down support. It operates across –40°C to +85°C and delivers up to 320Mbps data rate when both VCCA and VCCB ≥1.8V.

For engineers reviewing the SN74AVCH8T245PWG4 datasheet, SN74AVCH8T245PWG4 pinout, SN74AVCH8T245PWG4 application, or SN74AVCH8T245PWG4 equivalent, this page provides verified pin functions, dual-rail supply behavior, bus-hold current thresholds, VCC isolation timing, and real-world interface compatibility for mixed-voltage system design.

Technical Context

The SN74AVCH8T245PWG4 implements a fully configurable dual-rail architecture: A-port I/Os and control inputs (DIR, OE) are referenced to VCCA (1.2V–3.6V), while B-port I/Os reference VCCB (1.2V–3.6V). This enables asynchronous bidirectional translation without direction latching or external biasing.

Its VCC isolation feature forces outputs into high-impedance when either VCCA or VCCB = GND, and bus-hold circuitry sustains valid logic states on undriven A/B inputs-eliminating external pull resistors. Ioff limits backflow current during partial power-down, meeting JESD78 Class II latch-up and JESD22 ESD requirements (8kV HBM, 200V MM, 1kV CDM).

Key Specifications

Pinout & Package

TSSOP-24 (PW) package: 7.8 mm × 6.4 mm, 0.65 mm pitch, surface-mount, lead-free and RoHS-compliant.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LVC8T245PW and TXB0108PWR, SN74AVCH8T245PWG4 uniquely combines dual-rail independence, VCC isolation, bus-hold, and Ioff-making it the only choice for robust, mixed-voltage industrial and telecom backplane interfaces requiring fail-safe power sequencing.

Availability

SN74AVCH8T245PWG4 is available at Aetrix Electronics and suitable for industrial PLC backplanes, low-power IoT sensor hubs, enterprise SSD controllers, and telecom baseband FPGA interfaces requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for SN74AVCH8T245PWG4 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 specializing in analog, embedded processing, and connectivity technologies, with decades of experience in high-reliability interface solutions.

The SN74AVCH8T245 belongs to TI's AVC logic family, engineered specifically for low-voltage, mixed-rail system interconnects in industrial automation, communications infrastructure, and enterprise storage where voltage translation reliability and power sequencing safety are critical.

FAQ

What is the maximum allowable voltage on A-port or B-port I/O pins of SN74AVCH8T245PWG4?

The SN74AVCH8T245PWG4 supports 4.6V absolute maximum voltage on all A-port and B-port I/O pins, regardless of VCCA or VCCB supply values. This tolerance enables safe interfacing with higher-voltage systems (e.g., 5V legacy peripherals) without external clamping or series resistors, provided output current remains within ±50mA limits per pin.

How does SN74AVCH8T245PWG4 behave during power-up when VCCA and VCCB ramp at different rates?

SN74AVCH8T245PWG4 uses VCC isolation: if either VCCA or VCCB is at GND while the other is powered, all outputs enter high-impedance state automatically. This prevents bus contention and backfeeding. To ensure defined startup, OE must be tied to VCCA via a pullup resistor - minimum value determined by the driver's sink capability (typically 10kΩ for standard CMOS drivers).

Can SN74AVCH8T245PWG4 replace SN74AVC8T245 in existing designs?

Yes - SN74AVCH8T245PWG4 is a direct functional and pin-compatible upgrade to SN74AVC8T245, adding enhanced bus-hold strength, improved ESD ratings (8kV HBM), and tighter propagation delay consistency. No PCB changes are required; however, verify that VCCA-referenced DIR/OE timing margins remain sufficient under your operating conditions.

What is the purpose of the three GND pins (11, 12, 13) on SN74AVCH8T245PWG4?

The three dedicated GND pins on SN74AVCH8T245PWG4 reduce ground impedance and improve high-frequency noise rejection across the 24-pin TSSOP package. They provide separate return paths for A-port switching, B-port switching, and internal logic - minimizing crosstalk and ensuring stable bus-hold operation and clean 3-state transitions under dynamic load conditions.

Does SN74AVCH8T245PWG4 support hot-swap insertion in live backplanes?

Yes - SN74AVCH8T245PWG4 supports hot-swap via Ioff and VCC isolation features. When VCCA or VCCB is initially 0V, outputs remain in high-Z; once supply ramps, Ioff prevents backflow current from powered rails into unpowered ones. This meets IEC 61000-4-2 ESD immunity and avoids damage or system glitches during live insertion.