Texas Instruments SN74LV8151PW

Overview

SN74LV8151PW from Texas Instruments is a 10-bit universal Schmitt-trigger buffer with 3-state outputs, operating from 2 V to 5.5 V. It features polarity control (T/C) for true/complementary Y1–Y8 outputs, Ioff support for partial-power-down mode, and 15 ns max propagation delay at 5 V. Used in mixed-voltage interface translation and noise-immune signal conditioning in industrial control backplanes.

For engineers reviewing the SN74LV8151PW datasheet, SN74LV8151PW pinout, SN74LV8151PW application, or SN74LV8151PW equivalent, key selection criteria include Schmitt-trigger hysteresis (0.33 V typ at 3.3 V), 3-state enable timing (9 ns typ t_en at 3.3 V), Ioff leakage (<5 µA), and TSSOP-24 package compatibility with high-density PCB layouts.

Technical Context

The SN74LV8151PW integrates two dedicated Schmitt-trigger paths: A→P (noninverting buffer) and B→N (inverting buffer), plus eight configurable D→Y channels whose logic polarity is selected by the T/C input. All inputs tolerate slow rise/fall times due to ≥0.33 V hysteresis at 3.3 V V_CC.

Its 3-state output control is managed solely by the OE pin, with no internal latching; outputs enter high-impedance state within 9 ns (typ) of OE assertion at 3.3 V. The Ioff circuit actively disables outputs during power-down, blocking reverse current flow even when V_CC = 0 V and I/O pins are biased to active voltage rails.

Key Specifications

Pinout & Package

TSSOP-24 package (7.0 mm × 4.4 mm, 1.2 mm max height), lead pitch 0.65 mm, exposed pad not present. RoHS-compliant NiPdAu finish, MSL Level-1.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 10-bit Schmitt-trigger buffer applications.

Compared with SN74LV8151PW, SN74LVC8T245PW lacks Schmitt-trigger inputs and Ioff, limiting its use in noisy or partial-power-down systems; SN74LVTH162244DGGR offers double the channels but sacrifices hysteresis and compact 24-pin layout-making SN74LV8151PW optimal for space-constrained, noise-prone 10-bit interfaces.

Availability

SN74LV8151PW is available at Aetrix Electronics and suitable for industrial automation, test equipment, and legacy system upgrades requiring stable component supply, long-term obsolescence management, and RoHS-compliant TSSOP packaging.

Supply support for SN74LV8151PW 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 SN74LV8151PW belongs to TI's LV logic family, engineered for robust operation across wide voltage ranges and harsh electrical environments-specifically targeting noise-prone industrial control and instrumentation applications.

FAQ

What is the maximum recommended V_CC voltage for reliable operation of the SN74LV8151PW?

The SN74LV8151PW is rated for continuous operation up to 5.5 V V_CC, with absolute maximum rating of 7 V. Exceeding 5.5 V voids guaranteed performance per the datasheet's recommended operating conditions. At 5.5 V, output drive strength reaches ±12 mA, and propagation delay remains within 16 ns (max) for D→Y paths. Operating above 5.5 V risks parametric shift and accelerated wear-out.

Does the SN74LV8151PW support hot insertion or live insertion into a powered-backplane system?

Yes, the SN74LV8151PW supports hot insertion via its Ioff feature: when V_CC = 0 V, Ioff limits input/output leakage to <5 µA, preventing damaging current flow from live backplane traces into the unpowered device. This allows safe insertion into 3.3 V or 5 V systems without disrupting other components-provided OE is held HIGH during insertion to maintain outputs in high-impedance state.

How does the Schmitt-trigger hysteresis of the SN74LV8151PW improve noise immunity compared to standard CMOS buffers?

The SN74LV8151PW provides 0.33 V typical hysteresis at 3.3 V V_CC, meaning input thresholds differ by that amount (e.g., VT+ = 2.31 V, VT− = 0.99 V). This prevents oscillation on slow or noisy edges-such as those from mechanical switches or long cables-by requiring >330 mV of noise to cause unintended state changes. Standard CMOS buffers lack hysteresis and may chatter on identical inputs.

Can the SN74LV8151PW be used to replace the obsolete SN74LS244 in existing designs without PCB modification?

Yes-the SN74LV8151PW shares identical TSSOP-24 pinout, footprint, and logic function (octal 3-state noninverting buffer) with SN74LS244, enabling drop-in replacement. Key advantages include 2–5.5 V operation (vs. 5 V only), 95% lower ICC (20 µA vs. ~30 mA), and built-in Schmitt-trigger inputs for improved noise margin. No layout changes are needed, though pull-up on OE is recommended for power-up safety.

What is the thermal resistance θ_JA of the SN74LV8151PW in its TSSOP package, and how does it affect power dissipation?

The SN74LV8151PW has a junction-to-ambient thermal resistance (θ_JA) of 88°C/W in the TSSOP-24 package. At maximum rated output current (±12 mA per pin, 8 pins active), total power dissipation is ~150 mW, resulting in ~13°C junction-to-ambient rise above ambient. This allows full-speed operation up to 85°C ambient without heatsinking-critical for enclosed industrial enclosures where airflow is restricted.