STMicroelectronics 74VHC139TTR

Overview

74VHC139TTR from STMicroelectronics is a dual 2-to-4 line decoder/demultiplexer in TSSOP-16 package, operating from 2V to 5.5V, with 5.0 ns typical propagation delay at 5V, ±8 mA symmetrical output drive, and input tolerance up to 7V independent of VCC. It serves as address decoder in memory subsystems and data routing element in bus-controlled logic systems.

For engineers reviewing the 74VHC139TTR datasheet, 74VHC139TTR pinout, 74VHC139TTR application, or 74VHC139TTR equivalent, key selection criteria include enable-input gating capability, dual-decoder independence, 2KV ESD immunity, wide supply range compatibility, and 7V-tolerant inputs enabling 5V-to-3V interface bridging.

Technical Context

The device integrates two independent 2-to-4 decoders, each with active-low enable (1G/2G) and complementary address decoding logic. Inputs accept 0–7V regardless of VCC, supporting mixed-voltage system interfacing without level shifters.

Each decoder features balanced tPLH/tPHL propagation delays and symmetrical |IOH| = |IOL| ≥ 8 mA output drive. Power-down protection prevents latch-up during supply sequencing or hot insertion, and internal ESD structures provide 2 kV HBM immunity on all pins.

Key Specifications

Pinout & Package

TSSOP-16 package: 4.4 mm × 5.0 mm body, 0.65 mm pitch, 1.2 mm max height, gull-wing leads, moisture sensitivity level 1.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LV139APWR and 74HC139D,653, the 74VHC139TTR uniquely combines 5 ns speed, 7V input tolerance, and −55°C qualification-making it optimal for mixed-voltage, high-reliability, and fast-response applications where timing and robustness are co-critical.

Availability

74VHC139TTR is available at Aetrix Electronics and suitable for memory subsystems, industrial I/O expansion, mixed-voltage interface design, and bus-controlled peripheral selection requiring stable component supply across automotive, industrial automation, and embedded computing programs.

Supply support for 74VHC139TTR 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, Switzerland, designing and manufacturing analog, digital, and mixed-signal ICs for automotive, industrial, and consumer markets.

The 74VHC logic family targets high-speed, low-power, and robust interface solutions for mixed-voltage embedded systems-emphasizing noise immunity, wide supply range, and enhanced latch-up resistance.

FAQ

Is 74VHC139TTR pin-compatible with standard 74LS139?

Yes, it is pin- and function-compatible with 74LS139 and 74HC139, sharing identical TSSOP-16 footprint and truth table. However, it operates at higher speed (5 ns vs. 25 ns), lower power (4 µA vs. 15 mA), and supports wider voltage range (2–5.5 V vs. 4.75–5.25 V), making drop-in replacement feasible with performance gains.

Can 74VHC139TTR safely interface a 5 V microcontroller with a 3.3 V FPGA?

Yes. Its inputs tolerate up to 7 V regardless of VCC, allowing direct connection of 5 V address/control signals while powered from 3.3 V. Outputs swing rail-to-rail (0 V to 3.3 V), meeting 3.3 V logic thresholds with margin, and ±8 mA drive ensures reliable signal integrity.

What is the maximum capacitive load this device can drive reliably?

Test data specifies AC performance up to 50 pF load capacitance with tPD ≤ 9.5 ns at 5 V. For stable operation beyond 50 pF, series termination or buffer staging is recommended. The 26 pF CPD value indicates internal switching capacitance; total dynamic current scales linearly with fIN and CL per decoder.

Does 74VHC139TTR require external pull-up resistors on its outputs?

No. Its outputs are push-pull, not open-drain. Each Yx output actively drives high (VOH ≥ 4.4 V at 4.5 V VCC) and low (VOL ≤ 0.55 V at 8 mA). Pull-ups are unnecessary unless implementing wired-OR logic, which this device does not support natively.