STMicroelectronics M74HC126YRM13TR

Overview

M74HC126YRM13TR from STMicroelectronics is an automotive-grade quad 3-state bus buffer in SO14 package, operating from 2 V to 6 V, with 8 ns typical propagation delay at 6 V, ±6 mA output drive, and AEC-Q100 qualified for -40 °C to +125 °C environments - used in automotive body control modules for bidirectional data bus isolation.

For engineers reviewing the M74HC126YRM13TR datasheet, M74HC126YRM13TR pinout, M74HC126YRM13TR application, or M74HC126YRM13TR equivalent, key selection criteria include 3-state enable timing (tPZL/tPLZ ≤ 19 ns), high noise immunity (VNIH/VNIL ≥ 28 % VCC), rail-to-rail input compatibility, and automotive temperature compliance.

Technical Context

The device implements four independent non-inverting buffers, each with a dedicated active-high 3-state enable (G) input controlling output impedance. All inputs feature ESD protection (HBM: 2 kV, CDM: 1 kV) and transient voltage clamping.

Propagation delays are balanced (tPLH ≅ tPHL), output drive is symmetrical (|IOH| = IOL ≥ 6 mA), and DC input thresholds scale with VCC (VIH = 3.15 V min at 4.5 V, VIL = 1.35 V max), enabling robust interfacing across mixed-voltage logic domains.

Key Specifications

Pinout & Package

SO14 (Small Outline, 14-pin) package: 8.75 mm × 6.2 mm × 1.75 mm body, 1.27 mm pitch, gull-wing leads, RoHS-compliant ECOPACK®2.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74HC126QPWRQ1 and 74HC126D,653, the M74HC126YRM13TR offers the fastest propagation (8 ns typ), lowest ICC (4 μA max), and full AEC-Q100 Grade 1 validation - making it optimal for safety-critical automotive timing isolation where speed, leakage, and qualification are jointly constrained.

Availability

M74HC126YRM13TR is available at Aetrix Electronics and suitable for automotive body control modules, instrument clusters, engine diagnostics ports, and ADAS camera sequencing requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for M74HC126YRM13TR 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 microcontrollers, analog ICs, power devices, and automotive-grade logic.

The M74HC series delivers automotive-qualified, high-speed CMOS logic optimized for noise-immune, low-power operation in harsh-temperature vehicle subsystems - targeting body electronics, powertrain gateways, and infotainment interconnects.

FAQ

What is the maximum output current per channel for M74HC126YRM13TR?

The device guarantees minimum output drive of ±6 mA per channel under specified conditions (VOH at 4.5 V with IO = –6.0 mA; VOL at 4.5 V with IO = 6.0 mA). Absolute maximum DC output current is ±35 mA, but sustained operation above ±6 mA risks exceeding VOH/VOL specs and thermal limits in SO14 package.

Does M74HC126YRM13TR support 3.3 V-only operation?

Yes - it operates fully across 2 V to 6 V, including 3.3 V nominal supply. At VCC = 3.3 V, VIH is guaranteed ≥ 2.31 V and VIL ≤ 0.99 V, providing 0.5 V noise margin against 3.3 V LVTTL levels. Propagation delay increases to ~12 ns (typ), remaining compatible with 50 MHz bus timing.

How does the 3-state enable logic work on this device?

Each buffer has a dedicated active-high enable input (G1–G4 on pins 1, 4, 10, 13). When G = HIGH, the corresponding Y output follows the A input. When G = LOW, Y enters high-impedance state regardless of A value. No internal pull-ups or pull-downs exist on G inputs - external control logic must drive them definitively.

Is M74HC126YRM13TR pin-compatible with standard 74HC126?

Yes - it is functionally and physically pin-compatible with industry-standard 74HC126 in SO14 package, including identical pin numbering, electrical behavior, and truth table. The "Y" suffix denotes automotive qualification (AEC-Q100), not pinout deviation; all 14 pins retain identical roles and placement.