Texas Instruments SN74LVTH2245PWRG4

Overview

SN74LVTH2245PWRG4 from Texas Instruments is an octal bus transceiver IC designed for 3.3-V V_CC operation with mixed-mode 5-V input/output tolerance, enabling TTL-level interfacing between 3.3-V and 5-V data buses. It supports bidirectional data flow (A↔B), features bus-hold on all data inputs, integrated 22-Ω B-port series termination, and I_off/power-up 3-state for hot insertion in backplane or modular systems.

For engineers reviewing the SN74LVTH2245PWRG4 datasheet, SN74LVTH2245PWRG4 pinout, SN74LVTH2245PWRG4 application, or SN74LVTH2245PWRG4 equivalent, key selection criteria include its 20-pin TSSOP package, 2.7–3.6-V supply range, ±12 mA B-port drive, 4.2 ns typical A→B propagation delay at 3.3 V, and support for unregulated battery operation down to 2.7 V.

Technical Context

This device implements asynchronous bidirectional bus translation using DIR-controlled direction and OE-gated 3-state outputs. Its dual-voltage I/O architecture allows 5-V signals on A/B ports while operating from a 3.3-V V_CC, with input clamp protection up to 7 V and output voltage limits of V_CC±0.5 V in high state.

The integrated bus-hold circuit maintains valid logic levels on floating inputs without external resistors, and the B-port's built-in 22-Ω series resistance suppresses overshoot/undershoot during switching. Power-up 3-state ensures high-impedance outputs when V_CC is below 1.5 V, and I_off blocks current backflow during partial power-down.

Key Specifications

Pinout & Package

TSSOP-20 (PW) package: 6.95 mm × 4.4 mm × 1.2 mm body, 0.65-mm lead pitch, exposed pad not present, RoHS-compliant NiPdAu finish, MSL Level-1.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LVC2245APW and SN74AVC2245PW, the SN74LVTH2245PWRG4 uniquely combines 5-V-tolerant I/O, integrated bus-hold, I_off, and power-up 3-state in a single 20-pin TSSOP-making it the only option among the three qualified for hot-pluggable, mixed-voltage industrial backplanes.

Availability

SN74LVTH2245PWRG4 is available at Aetrix Electronics and suitable for industrial backplane interfaces, embedded controller expansion buses, automotive diagnostic modules, and test equipment data acquisition systems requiring stable component supply across extended temperature ranges (−40°C to 85°C).

Supply support for SN74LVTH2245PWRG4 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 over 50 years of innovation in industrial, automotive, and communications markets.

The SN74LVTH2245PWRG4 belongs to TI's LVTH logic family, engineered for robust mixed-voltage system interfacing in harsh environments-specifically targeting applications demanding hot insertion, bus stability without external biasing, and reliable operation across wide supply and temperature ranges.

FAQ

What is the maximum allowable input voltage on A/B ports of the SN74LVTH2245PWRG4?

The SN74LVTH2245PWRG4 supports input voltages up to 7 V on A and B ports, as specified in the Absolute Maximum Ratings table. This 5-V-tolerant capability allows direct connection to 5-V TTL or CMOS logic while operating from a 3.3-V V_CC, eliminating external level-shifting circuitry. Operation within recommended conditions requires VI ≤ 5.5 V.

Does the SN74LVTH2245PWRG4 require external pull-up or pull-down resistors on its data inputs?

No. The SN74LVTH2245PWRG4 integrates active bus-hold circuitry on all A and B port inputs, maintaining valid logic states on unused or floating lines without external resistors. Using pull-up/pull-down resistors with enabled bus-hold is explicitly discouraged in the datasheet, as it may cause contention or excessive current draw.

How does the SN74LVTH2245PWRG4 support hot-insertion in modular systems?

The SN74LVTH2245PWRG4 supports hot insertion via two complementary features: I_off circuitry disables outputs and blocks reverse current flow when V_CC = 0, and power-up 3-state forces outputs into high-impedance during power ramp-up (V_CC < 1.5 V). Together, these prevent bus conflicts and backfeeding during live card insertion or removal.

What is the purpose of the 22-Ω series resistance on the B-port outputs of the SN74LVTH2245PWRG4?

The B-port outputs of the SN74LVTH2245PWRG4 include built-in 22-Ω series resistors to dampen signal reflections and reduce overshoot/undershoot on transmission lines. This eliminates the need for discrete series termination resistors on B-side PCB traces, simplifying layout, saving board space, and improving signal integrity-especially in point-to-point or short-bus configurations.

Can the SN74LVTH2245PWRG4 operate reliably with a 2.7-V supply voltage?

Yes. The SN74LVTH2245PWRG4 is fully specified from 2.7 V to 3.6 V, including all electrical characteristics and switching parameters. Its design supports unregulated battery operation down to 2.7 V, making it suitable for portable or battery-backed industrial systems where supply voltage may sag under load or during discharge cycles.