Nexperia USA Inc. 74AHCT139D,118

Overview

74AHCT139D,118 from Nexperia is a dual 2-to-4 line decoder/demultiplexer in SO16 package, operating at 4.5–5.5 V supply with TTL-level inputs and active-low enable (nE) per section. It decodes binary address inputs (nA0/nA1) into four mutually exclusive active-low outputs (nY0–nY3), supporting 1-to-4 demultiplexing via nE as data input. Used in address decoding for memory-mapped peripherals in industrial control logic.

For engineers reviewing the 74AHCT139D,118 datasheet, 74AHCT139D,118 pinout, 74AHCT139D,118 application, or 74AHCT139D,118 equivalent, key selection criteria include TTL-compatible input thresholds (VIH = 2.0 V min, VIL = 0.8 V max), propagation delay ≤9.0 ns (VCC = 5 V, CL = 15 pF), overvoltage-tolerant inputs up to 5.5 V, and operation across –40 °C to +125 °C.

Technical Context

This device implements two independent 2-to-4 decoders, each with separate address inputs (1A0/1A1, 2A0/2A1), active-low enable (1E/2E), and active-low outputs (1Y0–1Y3, 2Y0–2Y3). Logic function follows standard truth table: when nE = LOW, outputs reflect decoded nA1nA0 (e.g., 00 → nY0 = LOW); when nE = HIGH, all outputs forced HIGH.

Input structure includes Schmitt-trigger action for noise immunity and overvoltage tolerance up to 5.5 V-enabling mixed-voltage interfacing (e.g., 3.3 V logic driving 5 V bus). Output drive capability is ±8 mA at VCC = 4.5 V, with VOL ≤0.55 V and VOH ≥3.70 V under load.

Key Specifications

Pinout & Package

74AHCT139D,118 uses the SO16 (SOT109-1) plastic small outline package: 16-pin, 3.9 mm body width, 1.27 mm lead pitch, surface-mount compatible.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 74AHCT139D,118, the 74HC139D,653 trades speed and TTL compatibility for ultra-low static power and wider voltage range, while the SN74LS139DR matches input levels but lacks extended temperature support and consumes significantly more supply current.

Availability

74AHCT139D,118 is available at Aetrix Electronics and suitable for memory address decoding, peripheral select logic, LED segment driver enable, and legacy bus expansion requiring stable component supply across industrial temperature ranges.

Supply support for 74AHCT139D,118 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

Nexperia is a leading semiconductor manufacturer specializing in high-performance logic, analog, and discrete components, with global manufacturing and R&D centers focused on reliability and efficiency.

The 74AHCT series targets industrial and automotive-adjacent applications requiring TTL-compatible CMOS logic with extended temperature operation and robust ESD protection (HBM >2000 V).

FAQ

Can 74AHCT139D,118 operate at 3.3 V supply?

No. The 74AHCT139D,118 is specified only for 4.5 V to 5.5 V operation. Its TTL input thresholds (VIH = 2.0 V min) and output drive characteristics are optimized for 5 V systems. Using it below 4.5 V risks unreliable switching, increased propagation delay, and potential failure to meet VIH/VIL margins - use 74AHC139D,118 instead for 3.3 V compatibility.

What is the maximum capacitive load this device can drive reliably?

The 74AHCT139D,118 is characterized up to 50 pF load capacitance, with propagation delay specified at both 15 pF and 50 pF (tpd ≤10.5 ns at VCC = 5 V). Driving loads beyond 50 pF increases delay nonlinearly and may cause signal integrity issues; for >50 pF, add a buffer stage or reduce trace length and parallel stubs.

How does the enable input function in demultiplexer mode?

When used as a 1-to-4 demultiplexer, the active-low enable (nE) serves as the data input: applying HIGH to nE forces all outputs HIGH (no data passed); applying LOW to nE allows the address inputs (nA0/nA1) to route that LOW signal to exactly one output (nY0–nY3), effectively distributing a single data bit across four paths.

Is this device suitable for automotive applications?

The 74AHCT139D,118 is qualified for –40 °C to +125 °C operation and meets AEC-Q100 stress test requirements for human body model ESD (≥2000 V), but Nexperia does not classify it as automotive-qualified unless explicitly marked "AEC-Q100 qualified" in ordering information. For safety-critical automotive use, verify qualification status via official Nexperia documentation before design-in.