Texas Instruments SN74HC158PWR

Overview

SN74HC158PWR from Texas Instruments is a 4-bit dual-input inverting data selector/multiplexer in TSSOP-16 package, operating from 2 V to 6 V, delivering 11 ns typical propagation delay at 6 V and ±6-mA output drive at 5 V. It routes one of two 4-bit data sources to inverted outputs under control of a common strobe (G) and select (A/B) inputs, used in digital logic routing, address decoding, and bus multiplexing in industrial control and instrumentation systems.

For engineers reviewing the SN74HC158PWR datasheet, SN74HC158PWR pinout, SN74HC158PWR application, or SN74HC158PWR equivalent, key selection criteria include its wide 2–6 V supply range, guaranteed 15 LSTTL load drive capability, low 80-µA max ICC, input transition time tolerance down to 400 ns at 6 V, and compatibility with HC logic families in space-constrained PCB layouts.

Technical Context

The SN74HC158PWR implements four independent 2:1 multiplexer channels with active-low enable (G) and shared select (A/B), where each Y output delivers the logical inverse of the selected A or B input. Its CMOS architecture ensures rail-to-rail output swing and high noise immunity across the full 2–6 V operating range.

All inputs accept TTL-level thresholds (VIH = 3.15 V min at VCC = 4.5 V; VIL = 1.35 V max), and outputs maintain defined logic states under load up to ±6 mA at 5 V. The device features no internal connections on pins 3, 10, and 12 in the PW package, as confirmed by TI's official top-view diagram and package addendum.

Key Specifications

Pinout & Package

TSSOP-16 (PW) package: 4.4 mm × 5.0 mm body, 0.65 mm lead pitch, 1.2 mm max height, RoHS-compliant NIPDAU finish, MSL Level-1, tape-and-reel packaging (2000 units/reel).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 2:1 inverting multiplexer applications.

Compared with SN74HC158PWR, SN74HC157DR provides identical functionality without inversion-critical for non-complementing data paths-while MC74HC158ADTR2G offers identical logic but demands more board space and exhibits lower thermal efficiency, making SN74HC158PWR optimal for compact, thermally constrained industrial PCBs.

Availability

SN74HC158PWR is available at Aetrix Electronics and suitable for industrial PLC I/O expansion, embedded system address decoding, and digital test equipment signal routing requiring stable component supply, long-term lifecycle assurance, and RoHS-compliant TSSOP packaging.

Supply support for SN74HC158PWR 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, with over 50 years of innovation in high-reliability logic ICs.

The SN74HC158PWR belongs to TI's 74HC logic family, designed for low-power, wide-supply-voltage digital signal routing in industrial, automotive, and communications equipment where pin compatibility and predictable timing are critical.

FAQ

What is the function of the G (strobe) pin on the SN74HC158PWR?

The G pin is an active-low enable input that controls output state: when G = high, all Y outputs are forced high-impedance (tri-stated); when G = low, the multiplexer operates normally, routing the selected A or B input to each Y output with inversion. This allows multiple SN74HC158PWR devices to share a common bus without contention.

Does the SN74HC158PWR support 3.3 V operation?

Yes, the SN74HC158PWR fully supports 3.3 V operation within its 2–6 V supply range. At VCC = 3.3 V, it maintains TTL-compatible input thresholds (VIH ≥ 2.0 V, VIL ≤ 0.8 V), delivers ≥±4 mA output drive, and achieves typical tpd ≈ 15 ns (CL = 50 pF), making it suitable for mixed-voltage 3.3 V/5 V system interfaces.

Are pins 3, 10, and 12 on the SN74HC158PWR internally connected?

No - pins 3, 10, and 12 on the SN74HC158PWR are explicitly designated as "No internal connection" (NC) in the TI datasheet and package drawings. These pins must remain unconnected on the PCB; routing or terminating them may cause mechanical stress or unintended coupling, violating TI's recommended layout guidelines.

How does the SN74HC158PWR differ from the SN74HC157 in practical design?

The SN74HC158PWR provides inverted outputs (Y = NOT(selected input)), whereas the SN74HC157 delivers true outputs (Y = selected input). Both share identical pinout, timing, and drive specs. This inversion difference dictates logic synthesis: SN74HC158PWR eliminates external inverters in complement-heavy paths, while SN74HC157 is preferred when polarity matching is required without added gates.

What is the maximum capacitive load the SN74HC158PWR can drive reliably?

The SN74HC158PWR is characterized for CL = 50 pF and 150 pF loads in its datasheet. At CL = 150 pF and VCC = 6 V, typical propagation delay increases to 33 ns and output transition time to 45 ns - still within specification. For reliable operation beyond 150 pF, external buffering is recommended, as excessive capacitance degrades timing margins and increases dynamic power dissipation in the SN74HC158PWR.