Diodes Incorporated PI74ST1G125CEX

Overview

PI74ST1G125CEX from Pericom Semiconductor is a single-channel 3-state buffer IC operating from 1.8V to 3.6V supply, featuring 1.8ns typical propagation delay (tPD), ±24mA output drive at 3V, and SC70-5 package. It serves as a level-shifting, bus-isolation buffer in low-voltage digital signal routing applications such as mobile SoC interconnects and portable sensor interface subsystems.

For engineers reviewing the PI74ST1G125CEX datasheet, PI74ST1G125CEX pinout, PI74ST1G125CEX application, or PI74ST1G125CEX equivalent, key selection criteria include 3-state enable timing (tPZH/tPLZ ≤ 7.5ns), input voltage tolerance up to 5.5V, and guaranteed operation across –40°C to +85°C industrial temperature range.

Technical Context

This device implements a non-inverting CMOS buffer with active-low 3-state control (OE), enabling bidirectional bus management without external logic. Its input structure supports overvoltage-tolerant operation up to 5.5V independent of VCC, while output stages deliver rail-to-rail swing and high sink/source capability under load.

The AC performance is characterized at CL = 15pF (high-speed mode) and CL = 50pF (bus-load condition), with propagation delays tightly specified across VCC = 1.8V/2.5V/3.3V and full temperature range. Power-down leakage (IOFF ≤ ±1μA) ensures signal integrity during system sleep states.

Key Specifications

Pinout & Package

Package: 5-pin SC70 (JEDEC MO-203B/AA), Pb-free & Green compliant, tape-and-reel (X suffix).

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LVC1G125DBVR and 74AUP1G125GW,125, PI74ST1G125CEX uniquely combines VCC-ratio input thresholds, 1.8ns speed, and ±24mA drive in SC70-making it optimal for compact, mixed-voltage, high-speed digital interconnects where timing and drive strength are critical.

Availability

PI74ST1G125CEX is available at Aetrix Electronics and suitable for mobile baseband interfaces, industrial sensor hubs, automotive infotainment links, and wearable health monitor data paths requiring stable component supply across extended temperature and mixed-voltage conditions.

Supply support for PI74ST1G125CEX 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

Pericom Semiconductor was a fabless provider of high-speed interface and signal-integrity solutions, acquired by Diodes Incorporated in 2016; its legacy timing, logic, and interface products remain in active production and support.

The PI74ST1G125 belongs to Pericom's SOTiny™ Gate family-designed specifically for space-constrained, low-voltage digital systems requiring fast, robust, and voltage-flexible signal buffering with minimal board area.

FAQ

Is PI74ST1G125CEX pin-compatible with standard 74LVC1G125 devices?

No. While both use SC70-5 packages, PI74ST1G125CEX assigns Pin 1 to AIN, Pin 3 to YOUT, and Pin 5 to OE-matching the JEDEC-standard 74LVC1G125 pinout. However, its VCC-ratio input thresholds and 1.8ns tPD differ from baseline LVC versions, requiring validation in timing-critical layouts.

Can PI74ST1G125CEX operate with VCC = 1.8V while accepting 3.3V inputs?

Yes. Its inputs tolerate –0.5V to +5.5V regardless of VCC setting. At VCC = 1.8V, VIH = 1.35V (0.75 × 1.8V) and VIL = 0.45V (0.25 × 1.8V), so a 3.3V logic HIGH is safely recognized as valid input without external level shifting.

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

It is characterized up to CL = 50pF with guaranteed tPD and timing specs. Driving >50pF may increase propagation delay and reduce edge rate; for loads exceeding 50pF, verify signal integrity via IBIS simulation or bench measurement using the provided CPD = 17pF value at 3.3V.

Does PI74ST1G125CEX require external pull-up or pull-down resistors on unused pins?

Yes. The datasheet explicitly states unused inputs (AIN, OE) must be held HIGH or LOW-they must not float. Pull-up/pull-down resistors (typically 10–100kΩ) are required on any unconnected input to prevent metastability, excessive ICC, or unintended 3-state activation.