Nexperia USA Inc. 74HC138D-Q100HL

Overview

74HC138D-Q100 from Nexperia is an automotive-grade 3-to-8 line inverting decoder/demultiplexer with CMOS logic levels, operating from 2.0 V to 6.0 V supply, qualified to AEC-Q100 Grade 1 (−40 °C to +125 °C), and housed in a 16-pin SO16 (SOT109-1) package. It features three enable inputs (E1, E2 active LOW; E3 active HIGH), eight mutually exclusive active LOW outputs (Y0–Y7), and supports memory chip select decoding and parallel expansion to 1-of-32 decoding.

For engineers reviewing the 74HC138D-Q100 datasheet, 74HC138D-Q100 pinout, 74HC138D-Q100 application, or 74HC138D-Q100 equivalent, key selection considerations include its automotive qualification, inverting output behavior, enable input logic configuration, propagation delay down to 12 ns at VCC = 6.0 V, and compatibility with both HC and HCT logic families in system-level address decoding.

Technical Context

The device implements a standard 3-input binary decoder with fully decoded active LOW outputs, where only one output is LOW at any time when all enables are asserted (E1 = LOW, E2 = LOW, E3 = HIGH). Its enable architecture supports cascading via E1/E2/E3 to build larger decoding trees without external logic.

Input clamping diodes allow interface to voltages exceeding VCC using current-limiting resistors, and the CMOS design ensures high noise immunity (>50% of VCC), low static current (≤8 μA typical at 25 °C), and latch-up immunity >100 mA per JESD78 Class II Level B.

Key Specifications

Pinout & Package

74HC138D-Q100 uses the SO16 plastic small outline package (SOT109-1), 16-pin, 3.9 mm body width, with gull-wing leads and standard pin 1 index marking.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 74HC138D-Q100, the 74HCT138D-Q100 offers seamless integration into mixed-voltage systems with TTL sources, while the SN74LS138DR trades automotive qualification and power efficiency for backward compatibility with legacy TTL logic families.

Availability

74HC138D-Q100 is available at Aetrix Electronics and suitable for engine control units, body control modules, and ADAS sensor interfaces requiring stable component supply across automotive production lifecycles.

Supply support for 74HC138D-Q100 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, high-reliability logic, analog, and discrete components for automotive, industrial, and consumer markets.

The 74HC138-Q100 belongs to Nexperia's automotive-qualified logic family, designed specifically for robust address decoding and signal routing in harsh-temperature, safety-critical vehicle subsystems.

FAQ

What is the maximum clock frequency supported by the 74HC138D-Q100?

The 74HC138D-Q100 is not a clocked sequential device-it has no internal clock and operates asynchronously. Its usable switching rate is governed by propagation delay (12 ns min at VCC = 6.0 V) and transition time (6 ns min), enabling reliable operation up to ~30 MHz address change rates in well-designed PCB layouts with proper termination and decoupling.

Can the 74HC138D-Q100 be used as a demultiplexer, and how?

Yes: connect the data signal to E1 (active LOW enable), hold E2 LOW and E3 HIGH, then use A0–A2 as the 3-bit channel select. Each output Y0–Y7 becomes a gated copy of the inverted data signal. This configuration requires no additional logic and maintains full automotive qualification and timing guarantees.

Does the 74HC138D-Q100 support 3.3 V microcontroller I/O directly?

Yes. At VCC = 3.3 V, VIH(min) = 2.1 V and VIL(max) = 1.35 V per datasheet Table 6, matching standard 3.3 V CMOS logic thresholds. Outputs swing rail-to-rail (VOH ≥ 3.15 V, VOL ≤ 0.26 V at IO = 4 mA), ensuring noise margins >0.6 V in typical automotive harness environments.

Is there a non-automotive version of this part, and what differs?

Yes-the industrial-grade 74HC138D (without -Q100 suffix) shares identical electrical specs and pinout but lacks AEC-Q100 qualification testing, extended temperature validation (−40 °C to +125 °C), and automotive-specific reliability reporting (e.g., HTOL, ESD, board-level vibration). It is not approved for safety-critical vehicle functions.