STMicroelectronics M74HC266RM13TR

Overview

M74HC266RM13TR from STMicroelectronics is a high-speed CMOS quad exclusive-NOR gate with open-drain outputs, fabricated using silicon gate C2MOS technology. It operates across 2V–6V supply, delivers 10ns typical propagation delay at 6V, supports ±25mA output current, and features high noise immunity (28% VCC min). It is used in level-shifting logic interfaces and wired-AND bus configurations in industrial control systems.

For engineers reviewing the M74HC266RM13TR datasheet, M74HC266RM13TR pinout, M74HC266RM13TR application, or M74HC266RM13TR equivalent, key selection criteria include open-drain output drive capability, wide VCC range compatibility, guaranteed noise margin, and TSSOP-14 package thermal performance for space-constrained PCB layouts.

Technical Context

The M74HC266RM13TR implements four independent EXNOR logic functions with open-drain outputs, requiring external pull-up resistors for active-high operation. Each gate exhibits rail-to-rail input voltage tolerance (0 to VCC) and supports mixed-voltage interfacing via configurable pull-up voltage.

Its C2MOS process ensures low static current (1µA max at 25°C) and robust ESD protection on all inputs. Propagation delay varies with supply voltage (10ns typ. at 6V, 48ns max. at 2V), and output transition time remains under 22ns across temperature ranges.

Key Specifications

Pinout & Package

TSSOP-14 package: 4.9 × 6.4 mm body, 0.65 mm pitch, 1.2 mm height, lead-free and RoHS compliant.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar quad EXNOR gate applications.

Compared with SN74LVC2G86DCUR and 74AHC266PW,118, the M74HC266RM13TR uniquely supports 6V operation and offers superior noise immunity (28% VCC), making it preferred for 5V industrial systems with EMI exposure and bus-wired logic topologies.

Availability

M74HC266RM13TR is available at Aetrix Electronics and suitable for industrial automation, sensor interface design, and legacy system upgrades requiring stable component supply and long-term lifecycle support.

Supply support for M74HC266RM13TR 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 analog, digital, and mixed-signal ICs for automotive, industrial, and consumer markets.

The M74HC266RM13TR belongs to ST's high-speed HC logic family, engineered for robustness in industrial control and factory automation where noise immunity, wide supply range, and open-drain flexibility are critical.

FAQ

Is M74HC266RM13TR pin-compatible with standard 74-series 266 devices?

Yes - it is pin- and function-compatible with industry-standard 74LS266 and 74HC266 in DIP, SO-14, and TSSOP-14 packages. Pin numbering and logic truth table match exactly, though electrical specs (e.g., VCC range, speed, drive strength) differ per technology node.

What pull-up resistor value is recommended for open-drain outputs?

A 4.7kΩ resistor to 5V is typical for 10MHz operation with ≤100pF bus capacitance. For 3.3V systems, use 2.2kΩ; for longer traces or higher capacitance, reduce to 1kΩ while verifying VOL remains <0.4V at max sink current.

Does M74HC266RM13TR support hot-swap or live-insertion?

No - it lacks hot-swap protection circuitry. Inputs are ESD-protected but not designed for powered insertion. Power sequencing must ensure VCC is stable before applying input signals to avoid latch-up or excessive ICC.

Can unused gates be left floating?

No - all inputs must be tied to VCC or GND. Floating inputs cause increased ICC, erratic output states, and potential oscillation due to intermediate voltage biasing of CMOS transistors. Unused outputs may remain unconnected.