Nexperia USA Inc. 74LVC138AD,112

Overview

74LVC138AD,112 from Nexperia is a 3-to-8 line inverting decoder/demultiplexer with three active-Low enable inputs (E1, E2) and one active-High enable input (E3), operating across 1.2 V to 3.6 V supply, delivering mutually exclusive outputs (Y0–Y7), and supporting mixed-voltage interfacing between 3.3 V and 5 V systems in memory chip select decoding applications.

For engineers reviewing the 74LVC138AD,112 datasheet, 74LVC138AD,112 pinout, 74LVC138AD,112 application, or 74LVC138AD,112 equivalent, key selection considerations include enable logic configuration (E1/E2 LOW + E3 HIGH), Schmitt-trigger input tolerance for slow edges, -40 °C to +125 °C operation, 5.8 ns max propagation delay at 3.3 V, and SO16 package compatibility with legacy PCB footprints.

Technical Context

The device implements a standard binary-decoded 3-input to 8-output logic function with inverted outputs, where only one Yn is LOW at any valid address/enable combination. Its triple-enable architecture enables cascading-e.g., four units plus one inverter achieve 5-to-32 line decoding without external logic.

All inputs feature Schmitt-trigger action, ensuring noise immunity and reliable switching with slow-rising/falling signals up to 20 ns/V (at VCC = 1.65 V). Output drive supports 50 Ω transmission lines at 125 °C, and overvoltage tolerance to 5.5 V allows direct interfacing with 5 V TTL sources while powered from 1.2 V–3.6 V supplies.

Key Specifications

Pinout & Package

74LVC138AD,112 is housed in a plastic small outline package (SO16, SOT109-1) with 16 leads, 3.9 mm body width, and standard 1.27 mm lead pitch - compatible with IPC-7351B SOIC-16 land patterns.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 3-to-8 decoder applications.

Compared with SN74LV138AIPWR, 74LVC138AD,112 provides guaranteed operation to +125 °C and 5.5 V input tolerance - critical for thermally demanding environments. Versus 74AHC138PW,118, it supports lower VCC (1.2 V) and faster timing at 3.3 V, making it optimal for modern low-voltage embedded designs.

Availability

74LVC138AD,112 is available at Aetrix Electronics and suitable for memory address decoding, peripheral chip select generation, I/O expansion with enable chaining, and mixed-voltage system interface requiring stable component supply across industrial temperature ranges.

Supply support for 74LVC138AD,112 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 global semiconductor expert focused on essential efficiency technologies - delivering high-performance, reliable, and scalable logic, analog, and MOSFET solutions for industrial, automotive, and consumer markets.

The 74LVC logic family targets low-voltage, high-speed digital interfacing with robust noise immunity and mixed-voltage compatibility - designed specifically for next-generation embedded controllers, programmable logic, and space-constrained industrial electronics.

FAQ

What is the maximum clock frequency supported by the 74LVC138AD,112 for address decoding?

The 74LVC138AD,112 does not operate on a clock; it is asynchronous. Its 5.8 ns max propagation delay at 3.3 V supports reliable decoding in systems with address valid windows ≥6 ns - enabling use in 160+ MHz bus cycles when combined with appropriate setup/hold margins and PCB trace length control.

Can the 74LVC138AD,112 be used as a demultiplexer, and how is that configured?

Yes: configure one active-LOW enable (e.g., E1) as the data input, tie E2 LOW and E3 HIGH to permanently enable, then apply A0–A2 as select lines. The selected Yn output mirrors the inverted E1 signal - providing true 1-to-8 demux functionality with no additional components required.

Does the 74LVC138AD,112 require external pull-up resistors on its outputs?

No. Outputs are push-pull CMOS with full rail-to-rail drive capability (±24 mA). Pull-ups are unnecessary unless open-drain emulation is explicitly needed - in which case external resistors must be sized to avoid violating VOL/VOH specs under load.

Is the SO16 package (SOT109-1) of the 74LVC138AD,112 RoHS compliant and lead-free?

Yes. The 74LVC138AD,112 in SO16 packaging meets RoHS Directive 2011/65/EU and is fully lead-free, with matte tin (Sn) termination finish and halogen-free molding compound - certified per Nexperia's Declaration of Conformity and material content reports.