Texas Instruments SN74LVC1G29DCTR

Overview

SN74LVC1G29DCTR from Texas Instruments is a single 2-of-3 decoder/demultiplexer IC operating from 1.65 V to 5.5 V, featuring 5.1 ns max propagation delay at 3.3 V, ±24-mA output drive, and Ioff support for live insertion and partial-power-down applications. It decodes two address inputs (A0, A1) into three active-low outputs (Y0–Y2) under enable control (G), used in address decoding and signal routing in compact logic subsystems.

For engineers reviewing the SN74LVC1G29DCTR datasheet, SN74LVC1G29DCTR pinout, SN74LVC1G29DCTR application, or SN74LVC1G29DCTR equivalent, key selection considerations include its DCT (SSOP-8) package, 3.3-V/5-V dual-supply compatibility, low ICC (10 µA max), Ioff-enabled back-drive protection, and guaranteed operation across –40°C to +85°C industrial temperature range.

Technical Context

The SN74LVC1G29DCTR implements positive-logic 2-of-3 decoding with active-low outputs: when G is low, exactly one of Y0–Y2 goes low based on A0/A1 state per function table; when G is high, all outputs are forced high. Its LVC-family CMOS design ensures TTL-compatible input thresholds and supports down-translation - inputs tolerate up to 5.5 V regardless of VCC.

It integrates Ioff circuitry that disables outputs during power-down, blocking current flow and enabling hot-swap capability. The device meets JESD 78 Class II latch-up immunity (>100 mA) and exceeds JESD 22 ESD ratings (2000-V HBM, 200-V MM, 1000-V CDM), making it suitable for mixed-voltage board interfaces and portable systems requiring robustness.

Key Specifications

Pinout & Package

SN74LVC1G29DCTR uses an 8-pin SSOP (DCT) package, 3.0 mm × 3.1 mm × 1.3 mm height, with gull-wing leads and pin 1 marked by a notch or beveled corner. Pin 1 is located at top-left in top-view orientation.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 2-of-3 decoder/demultiplexer applications.

Compared with SN74LVC1G29DCTR, SN74LVC1G139DCKR offers expanded output count at the cost of pin count and enable complexity, while 74AUP1G29GW,125 trades speed and voltage range for significantly lower static power - making each suitable only for distinct design priorities: density, power, or interface voltage.

Availability

SN74LVC1G29DCTR is available at Aetrix Electronics and suitable for industrial control panels, portable medical devices, and FPGA-based test equipment requiring stable component supply, long-term lifecycle assurance, and RoHS-compliant packaging.

Supply support for SN74LVC1G29DCTR 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 decades of experience in high-reliability logic families and advanced packaging technologies.

The SN74LVC1G29DCTR belongs to TI's LVC (Low-Voltage CMOS) logic series, designed for low-voltage, high-speed, mixed-signal interface applications in space-constrained industrial, computing, and communications systems.

FAQ

What is the maximum propagation delay of SN74LVC1G29DCTR at 3.3 V?

The maximum propagation delay (tpd) of SN74LVC1G29DCTR is 5.1 ns when operating at VCC = 3.3 V with CL = 15 pF, as specified in the Switching Characteristics table. This value applies to transitions from any input (A0, A1, or G) to any output (Y0–Y2) and ensures deterministic timing in high-speed address decoding applications. SN74LVC1G29DCTR maintains this performance across the full industrial temperature range (–40°C to +85°C).

Does SN74LVC1G29DCTR support 5-V input signals while powered from 1.8 V?

Yes, SN74LVC1G29DCTR supports input voltages up to 5.5 V regardless of VCC level, including when VCC = 1.8 V. This 5-V tolerant input capability is explicitly guaranteed in the datasheet's "Features" and "Recommended Operating Conditions" sections. SN74LVC1G29DCTR uses LVC-family input structures that allow safe interfacing with higher-voltage controllers without external level shifters - a key advantage in mixed-supply systems.

What is the purpose of the Ioff feature in SN74LVC1G29DCTR?

The Ioff feature in SN74LVC1G29DCTR disables all outputs and blocks current flow when VCC = 0 V, preventing damaging back-current through the device during partial power-down or hot-insertion events. This is critical for modular systems where boards may be inserted or removed while other sections remain powered. SN74LVC1G29DCTR guarantees Ioff ≤ ±10 µA, enabling robust live-insertion capability without external protection circuitry.

Which package type does SN74LVC1G29DCTR use, and what are its key mechanical dimensions?

SN74LVC1G29DCTR uses the DCT (SSOP-8) package: 3.0 mm × 3.1 mm body size, 1.3 mm maximum height, with 0.65 mm lead pitch and gull-wing leads. Pin 1 is identified by a beveled corner or notch at the top-left in top view. The package is RoHS-compliant, moisture sensitivity level 1 (unlimited floor life at ≤30°C/60% RH), and rated for reflow up to 260°C peak. SN74LVC1G29DCTR's DCT package enables high-density placement while maintaining hand-solderability and automated assembly compatibility.

Can SN74LVC1G29DCTR replace a standard 74HC138 in a 3.3-V system?

SN74LVC1G29DCTR cannot directly replace the 74HC138 because it is a 2-of-3 decoder (3 outputs), whereas the 74HC138 is a 3-to-8 line decoder (8 outputs) with different pinout, enable structure (three enables), and truth table. However, SN74LVC1G29DCTR is functionally appropriate where only three mutually exclusive outputs are needed - e.g., selecting among three peripherals. SN74LVC1G29DCTR offers advantages in size, power, and 5-V input tolerance, but replacement requires redesign of enable logic and output routing.