Texas Instruments SN74LVT240APWG4

Overview

SN74LVT240APWG4 from Texas Instruments is an octal buffer/line driver IC designed for 3.3-V V_CC operation with mixed-mode 5-V input/output compatibility, supporting TTL interfacing in mixed-voltage systems. It features dual 4-bit channels with independent output-enable (OE) controls, 64 mA sink current capability, and I_off/power-up 3-state for hot-insertion in backplane or modular systems.

For engineers reviewing the SN74LVT240APWG4 datasheet, SN74LVT240APWG4 pinout, SN74LVT240APWG4 application, or SN74LVT240APWG4 equivalent, key selection criteria include its 2.7–3.6 V supply range, ±100 µA I_off at V_CC = 0 V, <4.6 ns propagation delay at 3.3 V, and TSSOP-20 package suitability for space-constrained board-level voltage translation.

Technical Context

This device implements two independent 4-bit noninverting buffer sections, each controlled by a dedicated OE input. Logic operation follows positive-logic enable: outputs drive Y = A when OE is low, and enter high-impedance state when OE is high. Internal power-up 3-state circuitry ensures outputs remain high-Z during V_CC ramp from 0 to 1.5 V.

The SN74LVT240APWG4 integrates I_off protection that disables all outputs when V_CC = 0 V, preventing current backflow in live-insertion scenarios. Its input structure tolerates up to 5.5 V regardless of V_CC, enabling direct connection to 5-V logic while powered from 3.3 V - a core requirement for legacy system upgrades and FPGA I/O bridging.

Key Specifications

Pinout & Package

TSSOP-20 (PW) package: 6.5 mm × 4.4 mm body, 0.65 mm lead pitch, 1.2 mm max height, gull-wing leads, RoHS-compliant NiPdAu finish, MSL Level-1.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LVT240APWG4, SN74LVC240APWR reduces power consumption but sacrifices 5-V interface capability, while 74ALVC240MTCX offers similar packaging and pinout but lacks validated I_off behavior - making SN74LVT240APWG4 the preferred choice for mixed-voltage hot-swap systems requiring guaranteed back-current blocking.

Availability

SN74LVT240APWG4 is available at Aetrix Electronics and suitable for industrial backplane interfaces, FPGA I/O expansion, modular test equipment, and automotive diagnostic interfaces requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for SN74LVT240APWG4 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 90 years of innovation in industrial, automotive, and communications markets.

The SN74LVT240APWG4 belongs to TI's LVT (Low-Voltage BiCMOS Technology) logic family, engineered for high-speed, mixed-voltage interfacing in mission-critical infrastructure where reliability, ESD robustness, and hot-swap capability are mandatory design requirements.

FAQ

What is the maximum input voltage the SN74LVT240APWG4 can tolerate on its A inputs?

The SN74LVT240APWG4 supports input voltages up to 5.5 V on all A inputs, regardless of V_CC level. This 5-V tolerance is explicitly specified in the "Recommended Operating Conditions" table and enables direct interfacing with legacy 5-V logic without external level-shifting components. The SN74LVT240APWG4 maintains this rating across its full operating temperature range of −40°C to +85°C.

Does the SN74LVT240APWG4 support hot insertion, and what circuitry enables it?

Yes, the SN74LVT240APWG4 supports hot insertion via two integrated features: I_off circuitry that disables outputs and limits current to ±100 µA when V_CC = 0 V, and power-up 3-state logic that forces outputs into high-impedance during V_CC ramp from 0 to 1.5 V. These functions are verified per JESD 78 Class II latch-up testing and are explicitly cited in the device description for hot-insertion applications.

What is the propagation delay of the SN74LVT240APWG4 at 3.3 V supply?

The SN74LVT240APWG4 exhibits a maximum propagation delay of 4.6 ns (t_PLH and t_PHL) at V_CC = 3.3 V with CL = 50 pF, as specified in the "Switching Characteristics" table. Typical values are 2.2 ns (t_PLH) and 2.6 ns (t_PHL). This performance enables use in high-speed control buses and memory address/data latching where sub-5 ns timing is critical.

Can the SN74LVT240APWG4 be used with a 2.5-V supply?

No - the SN74LVT240APWG4 has a minimum recommended V_CC of 2.7 V per the "Recommended Operating Conditions" table. Operation below 2.7 V is not characterized or guaranteed; parameters such as VOL, VOH, and switching speed degrade outside this range. For 2.5-V systems, consider TI's LVC or ALVC families instead.

What package type does the SN74LVT240APWG4 use, and what are its key mechanical dimensions?

The SN74LVT240APWG4 uses the TSSOP-20 (PW) package: 6.5 mm × 4.4 mm body size, 0.65 mm lead pitch, 1.2 mm maximum height, and gull-wing surface-mount leads. Its JEDEC MO-153 registered outline and MSL Level-1 rating confirm suitability for standard reflow processes without moisture sensitivity concerns.