Texas Instruments SN74HCS151PWR

Overview

SN74HCS151PWR from Texas Instruments is an 8-to-1 CMOS multiplexer with Schmitt-trigger inputs, designed for data selection and routing in noise-prone or slow-slew environments. It operates from 2V to 6V, delivers ±7.8mA output drive at 6V, supports –40°C to +125°C ambient temperature, and features complementary Y/W outputs with active-low strobe (G) control.

For engineers reviewing the SN74HCS151PWR datasheet, SN74HCS151PWR pinout, SN74HCS151PWR application, or SN74HCS151PWR equivalent, key selection criteria include Schmitt-trigger hysteresis (ΔVT = 0.67–1.29V at 6V), propagation delay (7–17ns at 6V), low ICC (0.1–2µA), input leakage (±100nA), and TSSOP-16 package compatibility with industrial signal conditioning and digital bus arbitration systems.

Technical Context

The SN74HCS151PWR implements asynchronous 8:1 data selection using three binary address inputs (A, B, C) to route one of eight data sources (D0–D7) to the non-inverting Y output and inverted W output. The active-low strobe (G) overrides address logic to force Y = LOW and W = HIGH regardless of input states.

Schmitt-trigger inputs provide hysteresis (ΔVT up to 1.29V at 6V), enabling reliable operation with slow-rising/falling or noisy signals without external conditioning. Its balanced CMOS push-pull outputs support bidirectional current drive (±7.8mA at 6V) while maintaining rail-to-rail VOH/VOL performance across the full 2–6V supply range.

Key Specifications

Pinout & Package

TSSOP-16 (PW) package: 5.00mm × 4.40mm body, 0.65mm lead pitch, wettable flanks for AOI-compatible solder joint inspection.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 8-to-1 multiplexer applications.

Compared with SN74HCS151PWR, SN74LV151APWR trades Schmitt-trigger noise rejection for wider low-voltage compatibility, while CD74HC151M96 matches electrical specs but lacks hysteresis - making SN74HCS151PWR uniquely suited for harsh EMI environments where input signal integrity cannot be guaranteed.

Availability

SN74HCS151PWR is available at Aetrix Electronics and suitable for industrial data acquisition, automotive sensor multiplexing, digital bus arbitration, and test equipment signal routing requiring stable component supply across extended temperature and voltage ranges.

Supply support for SN74HCS151PWR 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 company specializing in analog and embedded processing solutions, with leadership in precision analog, power management, and high-reliability logic families.

The SN74HCS151PWR belongs to TI's HCS logic family, engineered for high-noise-immunity digital interfacing in automotive, industrial, and IoT edge devices where signal integrity and wide supply tolerance are critical.

FAQ

What is the maximum capacitive load SN74HCS151PWR can drive while meeting datasheet timing specifications?

The SN74HCS151PWR is characterized for CL = 50pF in its switching characteristics table. While it can drive larger loads, propagation delay increases nonlinearly beyond this point - for example, tpd may exceed 20ns at 100pF with 6V supply. To maintain guaranteed timing, keep total load capacitance ≤50pF including trace and receiver input capacitance. For heavier loads, add a buffer stage or reduce trace length.

Does SN74HCS151PWR require external pull-up or pull-down resistors on unused address inputs?

Yes - all unused inputs (A, B, C, D0–D7, G) must be terminated to VCC or GND. Although Schmitt-trigger inputs tolerate floating voltages better than standard CMOS, undefined logic states cause increased dynamic current and potential output instability. TI recommends 10kΩ pull-up/pull-down resistors; for G, tie to GND to enable normal operation unless strobe control is needed.

Can SN74HCS151PWR operate reliably at 2.5V supply voltage?

Yes - SN74HCS151PWR is fully specified from 2V to 6V. At 2.5V, VT+ = 1.18V (typ), VT− = 0.71V (typ), ΔVT = 0.47V (typ), and tpd = 28ns (max). Output drive drops to ±3.5mA, but remains sufficient for driving 74HCT inputs or light capacitive loads. Ensure all connected devices share the same 2.5V domain to avoid level-shifting issues.

How does the strobe (G) input affect output behavior when held HIGH?

When G is HIGH, the SN74HCS151PWR disables data selection regardless of A/B/C or D0–D7 states: Y is forced LOW and W is forced HIGH. This provides hardware-level channel disable capability - useful for fault isolation, power sequencing, or preventing glitches during address transitions. G must return LOW before valid data appears at Y/W.

Is thermal pad connection required for SN74HCS151PWR in TSSOP-16 (PW) package?

No - the PW package does not include a thermal pad. Only the WBQB (WQFN) variant has a thermal pad, which may be left floating or connected to GND. For SN74HCS151PWR, standard TSSOP-16 thermal management relies on PCB copper area under pins and proper GND/VCC plane design per TI's layout guidelines in section 8.4.2.