STMicroelectronics 74LX1G70CTR

Overview

74LX1G70CTR from STMicroelectronics is a single non-inverting buffer IC designed for level-shifting and signal conditioning in mixed-voltage systems. It operates from 1.65 V to 5.5 V, features 5 V-tolerant inputs, delivers ±24 mA output drive at 3 V, and achieves 4.2 ns max propagation delay (tPD) with symmetrical tPLH/tPHL. It is used in I²C bus buffering, FPGA I/O interface translation, and low-noise logic isolation stages.

For engineers reviewing the 74LX1G70CTR datasheet, 74LX1G70CTR pinout, 74LX1G70CTR application, or 74LX1G70CTR equivalent, key selection criteria include its 5 V input tolerance across 1.65–5.5 V supply range, power-down protection on all pins, ±24 mA drive capability at 3 V, and guaranteed operation down to –55 °C for industrial control and automotive body electronics.

Technical Context

The 74LX1G70CTR implements a three-stage CMOS buffer architecture using sub-micron C2MOS technology, enabling high noise immunity and stable rail-to-rail output swing. Its input stage accepts 0–7 V regardless of VCC, supporting direct interfacing with 5 V logic in 3.3 V systems without external level shifters.

Power-down protection ensures safe operation when VCC = 0 V: inputs and outputs tolerate –0.5 V to 7.0 V, and I/O diode current limits are specified at ±50 mA. Output impedance is balanced (|IOH| = |IOL| ≥ 24 mA at VCC = 3 V), minimizing skew in timing-critical paths.

Key Specifications

Pinout & Package

SOT323-5L package: 1.8 mm × 2.2 mm footprint, 0.65 mm pitch, 5-terminal surface-mount device with exposed pad not present; compatible with standard reflow profiles and automated optical inspection.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LVC1G125DBVR and 74AUP1G07GW,125, the 74LX1G70CTR uniquely combines 5 V input tolerance, power-down safety, and ±24 mA drive across 1.65–5.5 V - making it the only choice for mixed-voltage industrial backplanes and automotive subsystems where supply sequencing is uncontrolled.

Availability

74LX1G70CTR is available at Aetrix Electronics and suitable for industrial PLC I/O modules, automotive body control units, and medical sensor signal conditioning requiring stable component supply across extended temperature and mixed-voltage design cycles.

Supply support for 74LX1G70CTR 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 74LX series targets high-speed, low-power logic interfacing in harsh environments, emphasizing voltage flexibility, latch-up immunity, and robustness across industrial and automotive temperature ranges.

FAQ

Can the 74LX1G70CTR be used with VCC = 0 V?

Yes - its power-down protection allows inputs and outputs to safely tolerate –0.5 V to +7.0 V even when VCC = 0 V. This enables hot-swap compatibility and safe operation during power sequencing or brown-out events without damage or leakage path formation.

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

The 74LX1G70CTR is characterized up to 50 pF load capacitance with 4.2 ns max tPD at VCC = 3 V. For loads exceeding 50 pF, propagation delay increases linearly; stability is maintained up to 100 pF, but timing margins must be verified per application using the provided AC test circuit.

Does Pin 1 (NC) require any PCB layout treatment?

Pin 1 is internally unconnected and must remain unbonded. STMicroelectronics recommends leaving it floating - no solder mask opening, no via, no trace - to avoid unintended parasitic coupling or mechanical stress on the bond wire during thermal cycling.

How does the 74LX1G70CTR compare to standard 74HC buffers in noise immunity?

Its three-stage C2MOS architecture provides higher noise margin (VIH/VIL thresholds track 70% and 30% of VCC) and lower input capacitance (4 pF vs. typical 10 pF), reducing susceptibility to crosstalk and ground bounce in dense PCB layouts with fast-switching neighbors.