Texas Instruments SN74LV240APWR

Overview

SN74LV240APWR from Texas Instruments is an octal inverting buffer/driver with 3-state outputs, designed for 2V–5.5V V_CC operation. It delivers 16 mA output drive at 5 V, achieves 3.4 ns typical propagation delay (t_pd) under 5 V/15 pF conditions, and supports mixed-mode voltage translation with 5.5-V-tolerant inputs. It serves as a bus-oriented transceiver in memory address and clock distribution circuits.

For engineers reviewing the SN74LV240APWR datasheet, SN74LV240APWR pinout, SN74LV240APWR application, or SN74LV240APWR equivalent, key selection criteria include its dual 4-bit 3-state inverted buffer architecture, I_off support for live insertion, ground bounce (V_OLP) < 0.8 V at 3.3 V, and thermal resistance R_θJA = 128.2 °C/W in its TSSOP-20 package.

Technical Context

The SN74LV240APWR implements two independent 4-bit inverting buffer sections, each controlled by a dedicated output-enable (OE) input. When OE is low, inverted logic passes from A inputs to Y outputs; when OE is high, all eight outputs enter high-impedance state. This enables bidirectional bus control without external direction signals.

Its CMOS design features rail-to-rail output swing, 5.5-V-tolerant inputs regardless of V_CC, and I_off protection that limits power-off leakage to ≤5 µA per pin. The device meets JESD17 latch-up immunity (>250 mA) and supports operation across –40°C to +125°C ambient temperature.

Key Specifications

Pinout & Package

TSSOP-20 (PW) package: 6.50 mm × 6.40 mm body, 0.65 mm lead pitch, thin-profile surface-mount construction optimized for high-density PCB layouts.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LVC240APWR and 74ALVC240PW, the SN74LV240APWR uniquely balances wide supply range (2–5.5 V), 5.5-V input tolerance, and I_off protection-making it the only option among the three qualified for industrial backplane hot-swap and legacy 5 V peripheral interfacing.

Availability

SN74LV240APWR is available at Aetrix Electronics and suitable for industrial control, network infrastructure, and wearable electronics requiring stable component supply across extended temperature ranges and mixed-voltage architectures.

Supply support for SN74LV240APWR 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 SN74LV240APWR belongs to TI's LV-A series of low-voltage, high-noise-immunity logic devices, engineered specifically for reliable 3-state bus interfacing in mixed-supply systems with demanding ESD and thermal requirements.

FAQ

What is the maximum output drive capability of the SN74LV240APWR?

The SN74LV240APWR delivers ±16 mA output current at V_CC = 4.5–5.5 V, enabling direct drive of up to 10 LVTTL loads or 20 CMOS loads. At lower supplies (e.g., 2.3 V), it provides ±2 mA, maintaining functional compatibility across its full 2–5.5 V operating range. This drive strength is specified in the Electrical Characteristics table (Section 5.5) of the official SN74LV240APWR datasheet.

Does the SN74LV240APWR support hot-swap or live insertion?

Yes, the SN74LV240APWR supports live insertion via its I_off feature, which limits input/output leakage to ≤5 µA when V_CC = 0 V. This prevents back-driving powered circuitry and eliminates bus contention during board replacement. The specification is verified in Section 5.5 (Electrical Characteristics) and Feature Description (Section 7.3) of the SN74LV240APWR datasheet.

What is the thermal performance of the SN74LV240APWR in its TSSOP-20 package?

The SN74LV240APWR in PW (TSSOP-20) package has a junction-to-ambient thermal resistance (R_θJA) of 128.2 °C/W, a junction-to-board value (R_θJB) of 79.3 °C/W, and a junction-to-case (top) value (R_θJC(top)) of 70.5 °C/W. These values are measured per JESD51-7 and published in Section 5.4 of the SN74LV240APWR datasheet, confirming suitability for thermally constrained industrial PCB layouts.

Can the SN74LV240APWR interface between 5 V and 3.3 V logic domains?

Yes, the SN74LV240APWR accepts input voltages up to 5.5 V regardless of V_CC, allowing direct connection to 5 V peripherals while operating from a 3.3 V supply. Its outputs swing rail-to-rail (0 V to V_CC), so a 3.3 V V_CC yields 3.3 V logic-high levels compatible with 3.3 V receivers. This mixed-mode capability is documented in Section 7.3 (Feature Description) and Section 5.3 (Recommended Operating Conditions) of the SN74LV240APWR datasheet.

What is the propagation delay of the SN74LV240APWR at 3.3 V supply?

At V_CC = 3.3 V and C_L = 15 pF, the SN74LV240APWR exhibits a typical propagation delay (t_pd) of 4.6 ns and a maximum of 7.5 ns. Under heavier 50 pF loading, t_pd increases to 5.9–11 ns. These values are measured from A input to Y output and are specified in Section 5.7 (Switching Characteristics) of the SN74LV240APWR datasheet.