STMicroelectronics 74V1T126STR

Overview

74V1T126STR from STMicroelectronics is a high-speed CMOS single bus buffer with 3-state output, designed for level-shifting and bus isolation in 5V/3V mixed-voltage systems. It features 3.6ns typical propagation delay at 5V, ±8mA symmetrical drive strength, and input tolerance up to 7V independent of VCC. It is used in digital interface logic between microcontrollers and peripheral buses requiring fast, low-power, and robust voltage translation.

For engineers reviewing the 74V1T126STR datasheet, 74V1T126STR pinout, 74V1T126STR application, or 74V1T126STR equivalent, key selection criteria include its 4.5–5.5V operating range, power-down protected inputs, TTL-compatible thresholds (VIH ≥ 2V, VIL ≤ 0.8V), and SOT23-5L package compatibility with space-constrained PCB layouts.

Technical Context

This device implements a single-channel non-inverting buffer with active-low 3-state enable (1G). Its C2MOS sub-micron process enables rail-to-rail input tolerance (0–7V), allowing safe interfacing between 5V logic and 3V subsystems without external clamping.

Propagation delays are balanced (tPLH ≅ tPHL), and output impedance is symmetrical (|IOH| = IOL ≥ 8mA at VCC = 4.5V), ensuring consistent rise/fall timing and signal integrity in bidirectional bus environments.

Key Specifications

Pinout & Package

SOT23-5L surface-mount package: compact 2.8 × 2.6 mm footprint, 0.95 mm pitch, 5-terminal configuration with exposed pad not present.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar single-channel 3-state buffer applications.

Compared with SN74LVC1G125DBVR and 74AUP1G125GW,125, the 74V1T126STR uniquely supports 5V bus operation with 7V-tolerant inputs and sub-4ns delay - making it the only option for robust 5V mixed-signal interfacing without external protection.

Availability

74V1T126STR is available at Aetrix Electronics and suitable for industrial PLC I/O modules, automotive body control units, and embedded test equipment requiring stable component supply across extended temperature ranges (−55°C to +125°C).

Supply support for 74V1T126STR 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 74V series targets high-speed, low-power CMOS logic for voltage translation and bus buffering in harsh-environment applications demanding reliability and wide supply tolerance.

FAQ

Is the 74V1T126STR compatible with 3.3V logic inputs?

Yes - its inputs accept 0–7V regardless of VCC, so 3.3V signals meet VIH (≥2V) and VIL (≤0.8V) thresholds with full noise margin. No level-shifter is needed when driving from 3.3V sources into a 5V bus.

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

AC specifications are characterized up to 50pF load. With 8mA drive strength and 3.6ns typical delay at 15pF, it reliably drives ≤30pF traces or stubs in 5V systems; heavier loads require simulation or empirical validation.

Does the 74V1T126STR have built-in ESD protection?

It includes input diode clamping to VCC and GND per absolute maximum ratings (±20mA diode current), but no dedicated on-die ESD structures beyond standard CMOS gate protection. External TVS is recommended for IEC 61000-4-2 compliance in field-deployed systems.

Can the 74V1T126STR operate at 4.5V while driving a 5V bus?

Yes - its VCC operating range is 4.5–5.5V, and VOH is guaranteed ≥3.94V at IO = −8mA and VCC = 4.5V, satisfying 5V TTL high-level requirements (≥2.4V) with ample margin.