Texas Instruments SN74LVTH240DWRE4

Overview

SN74LVTH240DWRE4 from Texas Instruments is a 3.3-V ABT octal buffer/driver with 3-state outputs, designed for mixed-mode signal operation between 5-V inputs and 3.3-V V_CC. It features bus-hold on all data inputs, I_off support for hot insertion, and operates down to 2.7 V. Used in backplane interface and legacy bus bridging applications where level translation and output isolation are required.

For engineers reviewing the SN74LVTH240DWRE4 datasheet, SN74LVTH240DWRE4 pinout, SN74LVTH240DWRE4 application, or SN74LVTH240DWRE4 equivalent, key selection criteria include its 20-pin SOIC (DW) package, ±100 µA I_off current at V_CC = 0 V, 32 mA I_OL drive capability, and guaranteed operation from −40°C to +85°C.

Technical Context

This device integrates two independent 4-bit noninverting buffers, each with dedicated output-enable (OE) control. The ABT logic family enables TTL-compatible input thresholds while operating from a 3.3-V supply, supporting bidirectional voltage translation without external components.

Active bus-hold circuitry maintains valid logic states on undriven inputs, eliminating need for external pullup/pulldown resistors. Power-up 3-state and I_off protection ensure safe hot-insertion by disabling outputs during power transitions and preventing backflow current when powered down.

Key Specifications

Pinout & Package

SN74LVTH240DWRE4 is housed in a 20-pin SOIC (DW) package, 7.5 mm × 12.8 mm, 2.65 mm max height, RoHS-compliant NiPdAu lead finish, MSL Level-1.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar octal buffer/line driver applications.

Compared with SN74LVC240APWR and SN74AHCT240N, SN74LVTH240DWRE4 uniquely combines 5-V input tolerance, bus-hold, I_off, and 3.3-V operation-making it the sole option for robust, mixed-voltage, hot-pluggable bus interface in industrial control.

Availability

SN74LVTH240DWRE4 is available at Aetrix Electronics and suitable for industrial PLC backplanes, factory automation I/O expansion, and legacy bus bridging requiring stable component supply across extended temperature ranges and long product lifecycles.

Supply support for SN74LVTH240DWRE4 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 experience in industrial-grade interface ICs.

SN74LVTH240DWRE4 belongs to TI's ABT logic family, engineered specifically for reliable mixed-voltage bus interfacing in harsh environments where hot-swap capability, latch-up immunity, and wide supply tolerance are mandatory.

FAQ

What is the maximum output sink current for SN74LVTH240DWRE4?

The SN74LVTH240DWRE4 supports a maximum low-level output current (I_OL) of 64 mA per channel at V_CC = 3.3 V and T_A = 25°C. This rating is guaranteed across the full operating temperature range (−40°C to +85°C) and enables direct driving of moderate-power loads such as LEDs, small relays, or multiple TTL inputs without external amplification. The device maintains this drive strength while staying within absolute maximum ratings for junction temperature and power dissipation.

Does SN74LVTH240DWRE4 support hot insertion?

Yes, SN74LVTH240DWRE4 supports hot insertion through dual mechanisms: I_off circuitry disables outputs when V_CC = 0 V (limiting current to ±100 µA), and power-up 3-state forces outputs into high-impedance during supply ramp-up. These features prevent backdrive current and bus contention when the device is inserted into a live backplane or carrier, satisfying requirements for modular industrial systems compliant with IEC 61000-4-2 and MIL-STD-1344.

Can SN74LVTH240DWRE4 interface 5-V logic with a 3.3-V microcontroller?

Yes, SN74LVTH240DWRE4 is explicitly designed for this use case: its inputs tolerate up to 5.5 V regardless of V_CC level, while its 3.3-V supply allows seamless integration with modern microcontrollers. The device provides TTL-compatible input thresholds (V_IL = 0.8 V, V_IH = 2.0 V) and outputs compatible with both 3.3-V and 5-V receivers, making it ideal for bridging legacy peripherals to ARM Cortex-M or RISC-V-based controllers without external level shifters.

What is the purpose of bus-hold circuitry in SN74LVTH240DWRE4?

The bus-hold circuitry in SN74LVTH240DWRE4 actively maintains a valid logic state (high or low) on any undriven or floating data input, eliminating the need for external pullup or pulldown resistors. With ±750 µA dynamic hold current at V_CC = 3.6 V, it prevents metastability and noise susceptibility on unterminated bus lines-reducing BOM cost, PCB real estate, and design validation effort in systems with variable bus loading or intermittent signal sources.

What package type and dimensions does SN74LVTH240DWRE4 use?

SN74LVTH240DWRE4 uses a 20-pin SOIC (DW) package measuring 7.5 mm × 12.8 mm with a maximum height of 2.65 mm. It features gull-wing leads, NiPdAu lead finish, RoHS compliance, and a moisture sensitivity level (MSL) rating of Level-1 (unlimited floor life at ≤30°C/60% RH). The package drawing conforms to JEDEC MS-013 and includes recommended land patterns, stencil apertures, and solder paste volume guidelines for reliable reflow assembly.