Texas Instruments 74AC11138PWLE

Overview

74AC11138PWLE from Texas Instruments is a high-speed 3-to-8 line decoder/demultiplexer IC with three enable inputs (G1, G2A, G2B), designed for memory decoding and data routing in systems requiring sub-8 ns propagation delay at 5 V. It features active-low G2A/G2B and active-high G1 enables, center-pin VCC/GND layout to suppress switching noise, and operates across −40°C to 85°C.

For engineers reviewing the 74AC11138PWLE datasheet, 74AC11138PWLE pinout, 74AC11138PWLE application, or 74AC11138PWLE equivalent, this device is selected for low-latency address decoding in SRAM/ROM subsystems, bus demultiplexing in industrial controllers, and cascaded decoding architectures where enable-input logic minimizes external gate count.

Technical Context

The 74AC11138PWLE implements positive-logic decoding with binary-select inputs A, B, C driving eight active-low outputs (Y0–Y7). Its three independent enable inputs-G1 (active-high), G2A and G2B (both active-low)-allow flexible cascading: two 74AC11138PWLE devices implement a 24-line decoder without external inverters; three devices plus one inverter yield 32-line decoding.

Based on TI's EPIC™ 1-µm CMOS process, it delivers latch-up immunity of 500 mA at 125°C and supports rail-to-rail input/output operation (VI/VOL/VOH specified at 3 V, 4.5 V, and 5.5 V). Switching performance is characterized at both 3.3 V ±0.3 V and 5 V ±0.5 V, with tPHL/tPLH as low as 5.2 ns and 5.1 ns respectively at 5 V.

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.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 74AC11138PWLE, 74AC138D offers identical speed and drive but reduced enable flexibility, while SN74LV138APWR trades 30% higher propagation delay and halved output current for lower quiescent power and wider low-voltage operation - making 74AC11138PWLE optimal for industrial 5 V systems demanding minimal latency and robust fanout.

Availability

74AC11138PWLE is available at Aetrix Electronics and suitable for industrial control systems, high-speed memory subsystems, and programmable logic interface modules requiring stable component supply, long-term lifecycle support, and RoHS-compliant TSSOP packaging.

Supply support for 74AC11138PWLE 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 U.S.-based semiconductor company specializing in analog, embedded processing, and logic solutions, with over 90 years of innovation in industrial, automotive, and communications markets.

The 74AC11138PWLE belongs to TI's Advanced CMOS (AC) logic family, engineered for high-speed memory decoding and data-routing applications where propagation delay, noise immunity, and cascading flexibility are critical design constraints.

FAQ

What is the maximum propagation delay of the 74AC11138PWLE at 5 V?

The 74AC11138PWLE has a maximum propagation delay of 7.9 ns (tPHL) and 7.3 ns (tPLH) from address inputs A/B/C to any output Y, and 6.9 ns (tPHL) and 6.9 ns (tPLH) from G1 to any output, all measured at VCC = 5 V ± 0.5 V and TA = 25°C. These values ensure the 74AC11138PWLE introduces negligible delay in high-speed memory access paths.

Can the 74AC11138PWLE operate at 3.3 V supply voltage?

Yes, the 74AC11138PWLE is fully specified for operation from 3 V to 5.5 V. At VCC = 3.3 V, its typical propagation delay is 10.2 ns (tPLH) and 10.9 ns (tPHL), with VOH ≥ 2.48 V and VOL ≤ 0.44 V under load - meeting requirements for mixed-voltage 3.3 V/5 V system interfacing.

How does the enable-input configuration of the 74AC11138PWLE simplify decoder cascading?

The 74AC11138PWLE uses three enables - G1 (active-high), G2A and G2B (both active-low) - allowing direct implementation of 24-line decoding without external inverters. For example, G2A and G2B can select groups of eight outputs while G1 selects within-group lines, eliminating gate count and propagation delay from added logic.

Is the 74AC11138PWLE pin-compatible with standard 74AC138 devices?

No - although both are 3-to-8 decoders in the AC family, the 74AC11138PWLE has a distinct pinout: it places G2A and G2B on pins 1 and 2, whereas the 74AC138 uses pin 1 for G1 and pin 2 for G2. The 74AC11138PWLE requires dedicated PCB layout and cannot serve as a drop-in replacement for 74AC138 variants.

What is the latch-up immunity rating of the 74AC11138PWLE?

The 74AC11138PWLE provides 500-mA typical latch-up immunity at 125°C, achieved via Texas Instruments' EPIC™ (Enhanced-Performance Implanted CMOS) 1-µm process. This specification ensures robust operation in thermally demanding industrial environments where transient overcurrent events may occur.