STMicroelectronics 74V1G125CTR

Overview

74V1G125CTR from STMicroelectronics is a single 3-state bus buffer IC designed for voltage-level translation and bidirectional bus isolation in high-speed digital systems. It operates from 2V to 5.5V, delivers 3.8ns typical propagation delay at 5V, supports 0–7V input tolerance independent of VCC, and features symmetrical 8mA output drive capability. It is used in mixed-voltage interface circuits between 5V and 3V logic domains.

For engineers reviewing the 74V1G125CTR datasheet, 74V1G125CTR pinout, 74V1G125CTR application, or 74V1G125CTR equivalent, key selection criteria include 3-state enable timing (tPZH/tPLZ), input overvoltage tolerance, rail-to-rail input compatibility, and SOT323-5L package thermal and routing constraints.

Technical Context

The 74V1G125CTR implements a CMOS-based single-channel non-inverting buffer with active-high 3-state control (1G). Its input structure accepts voltages up to 7V regardless of VCC, enabling robust level-shifting without external clamping. The output stage provides matched pull-up/pull-down impedance (|IOH| = IOL ≥ 8mA at 4.5V) for clean signal integrity in shared-bus environments.

It uses sub-micron C2MOS technology with double-layer metal wiring, delivering low ICC (1µA max at 25°C) and improved latch-up immunity. Power-down protection ensures safe operation during power sequencing, and balanced tPLH ≅ tPHL minimizes duty-cycle distortion in clocked data paths.

Key Specifications

Pinout & Package

SOT323-5L package: ultra-small surface-mount outline (1.80 × 2.40 mm), 5-pin, lead pitch 0.65 mm, rated for −55°C to +125°C operation.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LVC1G125DBVR and 74AHC1G125SE-7, the 74V1G125CTR uniquely combines 7V input tolerance, SOT323-5L footprint, and sub-4ns propagation delay - making it optimal for compact, mixed-voltage industrial interfaces where pin compatibility and overvoltage resilience are mandatory.

Availability

74V1G125CTR is available at Aetrix Electronics and suitable for industrial sensor interface, automotive body control module, and portable medical monitor designs requiring stable component supply, long-term lifecycle support, and guaranteed SOT323-5L packaging consistency.

Supply support for 74V1G125CTR 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, specializing in automotive, industrial, and power management solutions with vertical manufacturing capabilities.

The 74V series targets high-speed, low-power logic interfacing in harsh-environment applications, emphasizing robustness, wide supply range, and legacy-compatible functionality for industrial control and instrumentation.

FAQ

Can the 74V1G125CTR safely interface a 5V microcontroller GPIO to a 3.3V FPGA input?

Yes. Its inputs tolerate 0–7V regardless of VCC, so a 5V GPIO can directly drive pin 2 (1A) while VCC = 3.3V. The output (pin 4) swings rail-to-rail between 0V and 3.3V, matching the FPGA's input thresholds. No external resistors or level shifters are needed.

What is the maximum capacitive load the 74V1G125CTR can drive while maintaining 3.8ns propagation delay?

The 3.8ns tPD is specified at CL = 15pF and VCC = 5.0V. At CL = 50pF, tPD increases to 4.3ns. For designs requiring ≤4ns delay, keep total load (including trace and input capacitance) below 20pF. Layout-dependent parasitics must be modeled to ensure timing closure.

Does the 74V1G125CTR require external pull-up or pull-down resistors on its 3-state control pin (1G)?

No. The 1G input has CMOS-compatible thresholds (VIH ≥ 0.7VCC, VIL ≤ 0.3VCC) and <1µA leakage, so it can be driven directly from another logic output. Pull resistors are only needed if the driving source floats during power-up or reset - in which case a 10kΩ pull-down ensures default high-impedance state.

How does the 74V1G125CTR behave when VCC is powered down to 0V while inputs remain at 5V?

It remains safe: power-down protection guarantees no reverse current flow or latch-up. Inputs accept 0–7V continuously, and internal circuitry isolates VCC from pins. However, output (1Y) becomes undefined - use external pull-down if bus state must be controlled during VCC ramp-down.