Texas Instruments SN74LVCH245PWLE

Overview

SN74LVCH245PWLE from Texas Instruments is an octal bus transceiver with 3-state outputs, designed for 2.7-V to 3.6-V V_CC operation and mixed-mode interfacing (5-V I/O with 3.3-V V_CC). It supports bidirectional data flow between A and B buses under DIR control, features bus-hold on all data inputs, and operates across –40°C to 85°C. Used in level-shifting backplane interfaces and isolated bus domains.

For engineers reviewing the SN74LVCH245PWLE datasheet, SN74LVCH245PWLE pinout, SN74LVCH245PWLE application, or SN74LVCH245PWLE equivalent, key selection criteria include 3-state isolation timing (t_dis ≤ 8.5 ns at 2.7 V), bus-hold elimination of external pullups, ±24-mA drive strength at 3 V, and PW package thermal performance (0.7 W max at 55°C).

Technical Context

The SN74LVCH245PWLE implements asynchronous bidirectional data transfer using separate DIR (direction) and OE (output enable) controls, with independent A→B and B→A paths. Its EPIC™ submicron CMOS process enables low ground bounce (V_OLP < 0.8 V) and undershoot immunity (V_OHV > 2 V) at 3.3 V.

Bus-hold circuitry actively maintains valid logic levels on floating A1–A8 and B1–B8 inputs without external components. The device tolerates input voltages up to 5.5 V while operating from a 2.7–3.6-V supply, enabling robust 5-V/3.3-V system interfacing.

Key Specifications

Pinout & Package

SN74LVCH245PWLE uses a 20-pin Thin Shrink Small-Outline (PW) package with 0.65-mm lead pitch and 7.2-mm × 4.4-mm body size. Thermal resistance θ_JA is 120°C/W (JEDEC Std 2S2P), supporting 0.7-W max power dissipation at 55°C ambient.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LVC245AQPWREP and 74ALVC245MTCX, the SN74LVCH245PWLE uniquely combines bus-hold integration, 5-V-tolerant I/O, and industrial temperature range in a cost-optimized PW package-making it ideal for space-constrained, mixed-voltage embedded systems where component count reduction is prioritized.

Availability

SN74LVCH245PWLE is available at Aetrix Electronics and suitable for industrial backplane interfaces, automotive body control modules, and embedded controller expansion buses requiring stable component supply, long-term lifecycle support, and consistent parametric performance across production batches.

Supply support for SN74LVCH245PWLE 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 logic solutions, with decades of expertise in high-reliability interface ICs and industrial-grade timing products.

The SN74LVCH245PWLE belongs to TI's LVCH logic family, engineered specifically for robust mixed-voltage system interfacing in industrial automation, automotive electronics, and test equipment where bus isolation, level translation, and noise immunity are critical.

FAQ

What is the maximum input voltage the SN74LVCH245PWLE can tolerate on its A/B port pins?

The SN74LVCH245PWLE supports input voltages up to 5.5 V on all A1–A8 and B1–B8 pins, regardless of V_CC level. This 5-V-tolerant feature allows direct connection to legacy 5-V peripherals without external level-shifting circuitry, simplifying system design and reducing bill-of-materials cost in mixed-voltage applications.

Does the SN74LVCH245PWLE require external pullup resistors on its data inputs?

No, the SN74LVCH245PWLE includes active bus-hold circuitry on all A and B port inputs, which maintains valid logic states on floating pins without external components. This eliminates the need for 16 discrete pullup or pulldown resistors, saving PCB area and assembly cost while improving reliability in systems with undriven or intermittently connected buses.

What is the recommended power-up sequence for the SN74LVCH245PWLE to ensure high-impedance outputs?

To guarantee high-impedance outputs during power-up, tie OE to V_CC through a pullup resistor (minimum value determined by driver sink capability). The SN74LVCH245PWLE does not have built-in power-on reset; this external bias ensures outputs remain disabled until system firmware asserts valid DIR and OE states, preventing bus contention at startup.

How does the SN74LVCH245PWLE handle ground bounce and output undershoot in high-speed switching?

The SN74LVCH245PWLE is characterized for low ground bounce (V_OLP < 0.8 V) and high undershoot immunity (V_OHV > 2 V) at V_CC = 3.3 V and 25°C. These specifications reflect its EPIC™ submicron CMOS process optimization, minimizing transient noise coupling that could disrupt adjacent analog circuits or cause false logic transitions in dense PCB layouts.

Is the SN74LVCH245PWLE pin-compatible with other members of the SN74LVC family?

The SN74LVCH245PWLE shares the same 20-pin PW package footprint and pinout with SN74LVC245A and SN74LVCH245 variants, but differs in bus-hold integration and absolute maximum ratings. While mechanical mounting is identical, functional substitution requires verification of bus-hold dependency and voltage tolerance requirements in the target application.