Texas Instruments SN74LV139APW

Overview

SN74LV139APW from Texas Instruments is a dual 2-line to 4-line decoder/demultiplexer in TSSOP-16 package, operating from 2 V to 5.5 V, with 7.5 ns max propagation delay at 5 V, mixed-mode voltage interface support, and I_off partial-power-down capability-used in high-speed memory address decoding and data routing subsystems.

For engineers reviewing the SN74LV139APW datasheet, SN74LV139APW pinout, SN74LV139APW application, or SN74LV139APW equivalent, this page delivers verified functional identity, confirmed TSSOP-16 pin mapping, real-world timing and voltage specifications, and two validated alternative parts for system-level design continuity.

Technical Context

The SN74LV139APW integrates two independent 2-to-4 line decoders with active-low enable (G) inputs per channel, enabling cascading and demultiplexing via G as a data control line. Each decoder features fully buffered inputs presenting one normalized load, and outputs are 3-state capable with guaranteed low-impedance drive under enabled conditions.

It supports mixed-voltage operation across all ports (e.g., 3.3 V inputs driving 5 V outputs), complies with JESD17 latch-up immunity (>250 mA), and includes I_off circuitry to block current flow during power-down-critical for hot-swap and partial-power-down systems.

Key Specifications

Pinout & Package

TSSOP-16 (PW) package: 5.00 mm × 6.4 mm body size, 0.65 mm lead pitch, 1.2 mm max height, gull-wing leads, RoHS-compliant NiPdAu or Sn finish, MSL Level-1.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual 2-to-4 decoder applications.

Compared with SN74LV139APW, SN74LV139APWR offers guaranteed production availability and logistics readiness, while SN74LV139ADR trades compactness for ease of assembly and thermal derating margin-both preserve identical decode behavior and timing performance.

Availability

SN74LV139APW is available at Aetrix Electronics and suitable for industrial control systems, memory subsystems, and peripheral interface designs requiring stable component supply and documented legacy compatibility.

Supply support for SN74LV139APW 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 digital interfaces.

The SN74LV139A series was designed for high-speed memory decoding and data-routing applications where low propagation delay, wide supply range, and robust power-down behavior are critical-targeting industrial, communications, and computing infrastructure.

FAQ

What is the maximum propagation delay of the SN74LV139APW at 3.3 V supply?

The SN74LV139APW has a maximum propagation delay of 13 ns at V_CC = 3.3 V ± 0.3 V with 15 pF load, measured from address or enable input transition to output valid edge. This value is specified across the full operating temperature range (–40 °C to +85 °C) and ensures reliable timing in 3.3 V systems such as ARM Cortex-M based controllers. The SN74LV139APW maintains consistent performance regardless of which channel (1 or 2) is active.

Does the SN74LV139APW support partial power-down mode?

Yes, the SN74LV139APW supports partial power-down mode via its I_off feature, which disables all outputs and blocks current flow when V_CC = 0 V. This prevents back-current from other powered rails into the device, making it suitable for use in multi-supply systems like FPGA I/O banks or hot-pluggable modules. The SN74LV139APW guarantees I_off ≤ 5 μA across –40 °C to +85 °C.

Is the SN74LV139APW pin-compatible with older 74LS139 devices?

The SN74LV139APW is functionally and pin-compatible with the 74LS139 in TSSOP-16 layout, sharing identical pin assignments, truth table, and active-low outputs. However, the SN74LV139APW operates from 2 V to 5.5 V (vs. 4.75–5.25 V for LS), offers lower power consumption, and provides improved noise immunity-making it a direct upgrade path without PCB changes. The SN74LV139APW retains full backward compatibility while enabling modern low-voltage designs.

What is the recommended bypass capacitor for the SN74LV139APW?

A 0.1 μF ceramic capacitor is recommended for bypassing the V_CC pin of the SN74LV139APW, placed as close as possible to the pin with a short, low-inductance connection to the ground plane. For enhanced high-frequency noise suppression, TI recommends paralleling a 1 μF capacitor. This configuration minimizes supply rail disturbance during fast output transitions and ensures stable operation across the full 2–5.5 V V_CC range of the SN74LV139APW.

Can the SN74LV139APW be used in mixed-voltage systems?

Yes, the SN74LV139APW supports mixed-voltage operation: inputs accept voltages from –0.5 V to V_CC + 0.5 V, allowing 3.3 V controllers to safely drive the device when powered from 5 V, or vice versa. Its output voltage swing tracks V_CC, and the device tolerates input overvoltage without damage. This capability makes the SN74LV139APW ideal for bridging voltage domains in heterogeneous systems-no external level shifters are needed for basic decode functions.