STMicroelectronics 74LVX139TTR

Overview

74LVX139TTR from STMicroelectronics is a low-voltage CMOS dual 2-to-4 decoder/demultiplexer with active-low enable inputs, operating from 2V to 3.6V supply, delivering 6.0ns typical propagation delay at 3.3V, 5V-tolerant inputs, and symmetrical 4mA output drive capability. It serves as address decoding and data routing logic in battery-powered 3.3V systems interfacing with 5V peripherals.

For engineers reviewing the 74LVX139TTR datasheet, 74LVX139TTR pinout, 74LVX139TTR application, or 74LVX139TTR equivalent, key selection criteria include its 5V-tolerant input voltage range (0–7V), low 2µA max quiescent current at 25°C, balanced tPLH/tPHL delays, and power-down protection enabling safe hot-swap operation in mixed-voltage digital subsystems.

Technical Context

The device implements two independent 2-to-4 decoders, each with an active-low enable (nG) controlling four active-low outputs (nY0–nY3). Address inputs (nA, nB) select one of four outputs per decoder while all others remain high when enabled.

Input protection allows 0–7V input voltage regardless of VCC, supporting robust level translation between 5V and 3.3V domains. Its C2MOS process ensures latch-up immunity and 2kV ESD tolerance on all I/O pins without external clamping.

Key Specifications

Pinout & Package

TSSOP-16 package (JEDEC MO-153, 4.4mm × 5.0mm body, 0.65mm pitch) with exposed pad not electrically connected. Pin numbering follows standard dual-in-line convention with GND (Pin 8) and VCC (Pin 16) at opposite ends.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LV139ADR and 74LVC139PW, the 74LVX139TTR uniquely combines guaranteed 5V-tolerant inputs with ultra-low 2µA standby current-making it optimal for mixed-voltage battery-powered systems where interface robustness and energy efficiency are jointly critical.

Availability

74LVX139TTR is available at Aetrix Electronics and suitable for memory address decoding, peripheral select logic, low-power IoT node design, and automotive body control modules requiring stable component supply across extended temperature ranges (−55°C to +125°C).

Supply support for 74LVX139TTR 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

STMicroelectronics is a global semiconductor leader headquartered in Geneva, designing and manufacturing analog, digital, and mixed-signal ICs for industrial, automotive, and consumer markets.

The 74LVX series targets low-voltage, low-power 3.3V logic interoperability with legacy 5V systems, emphasizing voltage tolerance, ESD robustness, and battery-life extension in portable and embedded applications.

FAQ

Can 74LVX139TTR operate with VCC = 2.0V and still meet timing specifications?

Yes. The datasheet guarantees full functionality-including propagation delay (tPLH/tPHL ≤14.0ns at 2.7V, CL=50pF) and output drive (IOL ≥4mA)-down to VCC = 2.0V across −55°C to +125°C. At 2.0V, tPD increases to ~16ns (max), but logic thresholds (VIH=1.5V, VIL=0.5V) remain valid, ensuring reliable operation in ultra-low-power modes.

What is the maximum capacitive load this device can drive while maintaining 6.0ns typical propagation delay?

The 6.0ns typical tPD is specified at CL = 15pF and VCC = 3.3V. With CL = 50pF, tPD increases to 7.6ns (typ.). The device reliably drives up to 70pF total load (including trace and input capacitance) while staying within AC limits; beyond that, delay degrades nonlinearly and output voltage swing may compress below VOL/VOLP specs.

Does the power-down protection apply to both inputs and outputs?

Power-down protection is explicitly implemented on all inputs (nG, nA, nB), allowing 0–7V signals regardless of VCC state. Outputs (nY0–nY3) are not protected during VCC = 0V; they float high due to internal pull-ups but must not be driven externally unless current-limited to ±20mA per absolute max ratings to avoid damage.

How does the 2kV HBM ESD rating impact PCB layout requirements?

The 2kV HBM rating means the device withstands typical handling ESD events without external protection. However, for board-level reliability in harsh environments (e.g., automotive or industrial), keep input traces short (<2cm), avoid stubs, and place 100nF ceramic decoupling caps within 3mm of VCC/GND pins-no series resistors or TVS diodes are needed for basic ESD compliance.