Texas Instruments 74LVC1G139DCTRE4

Overview

74LVC1G139DCTRE4 from Texas Instruments is a single 2-to-4 line decoder IC with active-low outputs, designed for high-speed memory decoding and data routing in 1.65-V to 5.5-V systems. It features 4.9 ns max propagation delay at 3.3 V/15 pF, ±24-mA output drive capability, and Ioff support for live insertion and partial-power-down operation. It is used in SSDs, AV receivers, and HD TV address decoding.

For engineers reviewing the 74LVC1G139DCTRE4 datasheet, 74LVC1G139DCTRE4 pinout, 74LVC1G139DCTRE4 application, or 74LVC1G139DCTRE4 equivalent, key selection criteria include its dual-input address decode function, low-voltage compatibility down to 1.65 V, guaranteed 5.5-V tolerant inputs, nanosecond-scale timing performance, and SM8 package footprint for space-constrained PCB layouts.

Technical Context

The 74LVC1G139DCTRE4 implements a standard 2-bit binary decoder with B as MSB and A as LSB, driving four active-low outputs (Y0–Y3) based on input combinations. Its logic is fully static CMOS, with no internal latches or clocks.

It supports voltage translation: inputs accept up to 5.5 V regardless of VCC (1.65–5.5 V), enabling interfacing between mixed-voltage domains. The Ioff feature disables outputs when VCC = 0 V, preventing back-drive current and supporting hot-plug scenarios.

Key Specifications

Pinout & Package

74LVC1G139DCTRE4 uses the SM8 (8-pin Small Outline Package) with nominal body size 2.95 mm × 2.80 mm and standard SSOP lead pitch (0.65 mm). The package is RoHS-compliant, tape-and-reel packaged (3000 units/reel), and rated MSL-1 (unlimited floor life at ≤30°C/60% RH).

Key Features

Applications

Equivalent & Alternatives

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

Compared with 74LVC1G139DCTRE4, the DCURG4 offers superior thermal performance in a smaller footprint but demands higher-precision placement, while the YZPR delivers the smallest possible solution at the cost of more complex PCB routing and assembly validation.

Availability

74LVC1G139DCTRE4 is available at Aetrix Electronics and suitable for SSDs, AV receivers, HD TVs, and industrial tablets requiring stable component supply, long-term lifecycle assurance, and consistent parametric performance across production batches.

Supply support for 74LVC1G139DCTRE4 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 90 years of innovation in high-reliability electronic components.

The SN74LVC1G139 product line delivers ultra-small, low-power, voltage-flexible logic decoders optimized for memory expansion, peripheral selection, and signal routing in space- and power-sensitive consumer and industrial systems.

FAQ

What is the maximum propagation delay of the 74LVC1G139DCTRE4 at 3.3 V?

The 74LVC1G139DCTRE4 has a maximum propagation delay (tpd) of 4.9 ns at VCC = 3.3 V with a 15-pF load, as specified in the Switching Characteristics table of the official TI datasheet SCES602E. This value applies to both A→Y and B→Y paths and ensures minimal added latency in high-speed decode applications such as SSD controller interfaces.

Does the 74LVC1G139DCTRE4 support mixed-voltage operation between 1.8-V and 5-V domains?

Yes, the 74LVC1G139DCTRE4 supports true mixed-voltage operation: its inputs tolerate up to 5.5 V regardless of VCC, which can range from 1.65 V to 5.5 V. This allows a 1.8-V-powered 74LVC1G139DCTRE4 to safely accept 5-V address signals - eliminating external level shifters in legacy-to-modern system interfaces.

What package type does the 74LVC1G139DCTRE4 use, and what are its dimensions?

The 74LVC1G139DCTRE4 uses the SM8 (Small Outline Package, 8-pin) with nominal body dimensions of 2.95 mm × 2.80 mm and 0.65-mm lead pitch. It is RoHS-compliant, MSL-1 rated, and supplied in 3000-unit tape-and-reel format - making it compatible with standard SMT pick-and-place equipment and reflow profiles.

How does the Ioff feature of the 74LVC1G139DCTRE4 protect the system during partial power-down?

The Ioff feature in the 74LVC1G139DCTRE4 disables all outputs when VCC = 0 V, blocking current flow from live inputs or outputs into the unpowered device. This prevents damaging back-drive current in hot-swap or modular systems - a critical safeguard confirmed in TI's characterization per JESD78 Class II latch-up testing.

Can unused inputs on the 74LVC1G139DCTRE4 be left floating?

No, unused inputs on the 74LVC1G139DCTRE4 must be tied to either VCC or GND. Floating CMOS inputs cause undefined logic states, increased power consumption, and potential oscillation or ESD susceptibility. TI explicitly recommends biasing all unused inputs to a valid logic level - typically GND for A/B if not needed - to ensure reliable operation.