Texas Instruments SN74LV240APWT

Overview

SN74LV240APWT from Texas Instruments is an octal inverting buffer/driver with 3-state outputs, designed for 2V to 5.5V V_CC operation. It delivers 6.5ns max propagation delay at 5V, supports mixed-mode voltage translation (inputs tolerant to 5.5V), and features I_off for live insertion and partial power-down. It serves as a bus-oriented receiver/transmitter in memory address and clock distribution systems.

For engineers reviewing the SN74LV240APWT datasheet, SN74LV240APWT pinout, SN74LV240APWT application, or SN74LV240APWT equivalent, key selection criteria include its 20-pin TSSOP package, dual 4-bit inverted 3-state architecture, 8mA output drive at 3.3V, ground-bounce suppression (<0.8V), and compatibility with 2–5.5V logic domains in high-density PCB layouts.

Technical Context

The SN74LV240APWT implements two independent 4-bit inverting buffer sections, each controlled by a dedicated output-enable (OE) input. When OE is low, data passes inverted from A inputs to Y outputs; when OE is high, all eight outputs enter high-impedance state - enabling bidirectional bus sharing without contention.

Its CMOS design ensures rail-to-rail output swing, 5.5V-tolerant inputs across all V_CC conditions (2–5.5V), and robust ESD protection (±2000V HBM). The device meets JESD17 latch-up immunity (>250mA) and supports stable operation from –40°C to +125°C.

Key Specifications

Pinout & Package

TSSOP-20 (PW) package: 6.50mm × 6.4mm body, 0.65mm pitch, thin-profile surface-mount construction optimized for high-density routing and thermal performance (R_θJA = 128.2°C/W).

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LVC240APW, SN74LV240APWT offers superior mixed-voltage interoperability due to 5.5V-tolerant inputs across all V_CC levels; versus 74AHC240PW, it delivers lower dynamic power and improved ground-bounce suppression - critical in noise-sensitive portable and industrial systems.

Availability

SN74LV240APWT is available at Aetrix Electronics and suitable for industrial automation, wearable electronics, and network infrastructure applications requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for SN74LV240APWT 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 for industrial, automotive, and communications markets.

The SN74LV240APWT belongs to TI's LV-A family of low-voltage, high-speed logic devices engineered for robust mixed-signal interfacing in space-constrained, thermally demanding applications.

FAQ

What is the maximum propagation delay of the SN74LV240APWT at 3.3V?

The SN74LV240APWT has a maximum propagation delay (t_pd) of 7.5ns at V_CC = 3.3V with 15pF load, as specified in Section 5.7 of the official datasheet. This value is measured under standard test conditions (T_A = 25°C) and guarantees timing compliance in high-speed bus applications such as memory addressing and clock distribution where sub-10ns latency is required. The SN74LV240APWT maintains consistent performance across its full operating temperature range (–40°C to +125°C).

Does the SN74LV240APWT support 5V-tolerant inputs when powered from 3.3V?

Yes, the SN74LV240APWT supports 5.5V-tolerant inputs regardless of V_CC level - including when powered from 3.3V. This capability is explicitly confirmed in Section 7.3 ("Feature Description") and Table 5.3 ("Recommended Operating Conditions"), allowing direct connection to 5V control signals without external level-shifting circuitry. This feature makes the SN74LV240APWT especially valuable in mixed-voltage systems like industrial PLCs or multi-rail wearables where legacy 5V peripherals interface with modern 3.3V processors.

What is the purpose of the I_off specification in the SN74LV240APWT?

The I_off specification (≤5µA at V_CC = 0V) in the SN74LV240APWT enables safe live insertion and partial power-down operation by preventing back-drive current flow through powered-off sections of the IC. As documented in Section 7.3 and Table 5.5, this feature protects upstream drivers during hot-swap events or system sleep modes - critical in modular computing, telecom line cards, and battery-powered devices where subsystems power up/down independently. The SN74LV240APWT maintains this behavior across its full –40°C to +125°C operating range.

How does the SN74LV240APWT handle ground bounce and output undershoot?

The SN74LV240APWT is characterized for low ground bounce (V_OLP < 0.8V at V_CC = 3.3V, T_A = 25°C) and controlled output undershoot (V_OHV > 2.3V under same conditions), as stated in Section 1 "Features". These parameters reflect internal design optimizations - including balanced output stage layout and controlled slew rate - that minimize simultaneous switching noise on shared PCB ground planes. This directly improves signal integrity in dense, multi-channel digital systems where the SN74LV240APWT buffers clocks or address lines.

Can the SN74LV240APWT be used as a direct replacement for the obsolete SN74LV240APW?

Yes, the SN74LV240APWT is the active, tape-and-reel packaged version of the SN74LV240APW (listed as Obsolete in TI's Package Addendum). Both share identical electrical specifications, pinout, and TSSOP-20 (PW) footprint. The "T" suffix denotes tape-and-reel packaging (2000 units per reel), while the base part number remains functionally identical. TI confirms full compatibility in Section 11 of the SCLS384K datasheet, making SN74LV240APWT the recommended production-grade variant for new designs and BOM refreshes.