STMicroelectronics M74HC125RM13TR

Overview

M74HC125RM13TR from STMicroelectronics is a high-speed CMOS quad 3-state bus buffer with independent enable inputs, operating from 2V to 6V supply. It delivers 8ns typical propagation delay at 6V, ±6mA symmetrical output drive, and 4μA max quiescent current at 25°C - used in bidirectional data bus isolation and level translation in industrial control logic.

For engineers reviewing the M74HC125RM13TR datasheet, M74HC125RM13TR pinout, M74HC125RM13TR application, or M74HC125RM13TR equivalent, key selection criteria include 3-state timing (tPZL/tPLZ), noise immunity (28% VCC), output impedance balance, wide voltage range compatibility, and TSSOP-14 package constraints for high-density PCB layouts.

Technical Context

The M74HC125RM13TR implements four independent non-inverting buffers, each with an active-high 3-state enable input (1G–4G). All outputs enter high-impedance state when corresponding G is high, enabling bidirectional bus sharing without contention.

Designed using silicon gate C2MOS technology, it features integrated ESD protection on all inputs, rail-to-rail input voltage tolerance (0 to VCC), and guaranteed operation across –55°C to +125°C. Propagation delays tPLH and tPHL are balanced (≤1ns mismatch at 6V), supporting clean signal integrity in synchronous systems.

Key Specifications

Pinout & Package

TSSOP-14 (Thin Shrink Small Outline Package), 4.9 × 6.4 mm body, 0.65 mm pitch, lead-free and RoHS-compliant.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74HC125PW and 74VHC125FT, the M74HC125RM13TR offers broader 2–6V operation and superior 125°C high-temp performance, making it optimal for industrial and extended-temperature embedded systems where voltage margin and thermal robustness outweigh marginal speed gains.

Availability

M74HC125RM13TR is available at Aetrix Electronics and suitable for industrial PLC backplanes, automotive body control modules, test equipment signal routing, and medical diagnostic data acquisition requiring stable component supply across extended temperature ranges.

Supply support for M74HC125RM13TR 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 microcontrollers, power ICs, sensors, and discrete components for industrial, automotive, and consumer markets.

The M74HC125 belongs to ST's high-speed HC logic family, engineered for robust noise immunity, low static power, and seamless interoperability with legacy 74-series logic in space-constrained industrial control designs.

FAQ

Can M74HC125RM13TR operate reliably at 2.0V supply?

Yes. The device is fully specified down to 2.0V: VIH = 1.5V (min), VOL = 0.1V (max at 20μA), and tPD = 75ns (max at CL = 50pF). It maintains functional 3-state behavior and input noise immunity (28% of 2.0V = 0.56V) across the full –55°C to +125°C range.

What is the maximum capacitive load this buffer can drive while maintaining timing specs?

At VCC = 4.5V, the M74HC125RM13TR drives up to 150pF with tPLH/tPHL ≤27ns and tTLH/tTHL ≤18ns. Driving >150pF increases propagation delay nonlinearly and may exceed 10% duty cycle distortion in clock-forwarding use - add series termination or reduce trace length beyond this limit.

Is the TSSOP-14 package of M74HC125RM13TR compatible with standard reflow profiles?

Yes. The device complies with JEDEC J-STD-020D moisture sensitivity level 1 (MSL1) and supports peak reflow temperatures up to 260°C for 30 seconds. Its 0.65mm pitch and 0.75mm max package height allow compatibility with standard Type II stencil apertures and automated optical inspection.

How does the 3-state enable timing affect bus arbitration in multi-master systems?

tPZL (enable-to-output-low) and tPLZ (disable-to-high-Z) are both 19ns (max) at VCC = 6V. This ensures <38ns total window for safe bus release before another master asserts - sufficient for 10MHz I²C/SPI arbitration when combined with slew-rate controlled drivers and proper pull-up sizing.