STMicroelectronics X0115MUF

Overview

X0115MUF from STMicroelectronics is a 1 A sensitive-gate SCR thyristor in SMBflat-3L package, designed for low-current gate triggering (30–150 µA) in high-reliability protection circuits. It delivers 600 V repetitive blocking voltage, 750 V non-repetitive surge rating, and 28 µs turn-on time-enabling fast crowbar response in GFCI and AFCI modules operating at 125 °C junction temperature.

For engineers reviewing the X0115MUF datasheet, X0115MUF pinout, X0115MUF application, or X0115MUF equivalent, key selection criteria include gate sensitivity under 150 µA, functional isolation up to 250 V (UL 840), dV/dt immunity ≥80 V/µs at 125 °C, and thermal resistance R_th(j-l) = 15 °C/W for SMT-based fault-interrupting power designs.

Technical Context

The X0115MUF operates as a latching unidirectional switch with precise gate-controlled turn-on and current-dependent commutation. Its 0.9 V threshold on-state voltage (V_TO) and 230 mΩ dynamic resistance ensure minimal conduction loss at 1 A RMS, while the 80 V/µs dV/dt immunity at T_j = 125 °C prevents false triggering in noisy AC line environments.

Thermal design relies on its 15 °C/W junction-to-lead resistance and 3.4 mm creepage distance, enabling stable operation up to 125 °C junction temperature on 5 cm² copper pads. The device sustains 12 A non-repetitive surge current for 8.3 ms, supporting transient overvoltage clamping without latch-up.

Key Specifications

Pinout & Package

SMBflat-3L is a surface-mount, ultraflat 3-terminal package with anode (A), cathode (K), and gate (G) terminals arranged in a single-row configuration. Its 3.4 mm creepage and 0.15–0.40 mm lead thickness support automated reflow assembly and high-voltage isolation in space-constrained PCBs.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar SCR-based protection applications.

Compared with MCR106-6 and VS-ST01-06, the X0115MUF uniquely combines ultra-low gate sensitivity (30 µA), fast 28 µs turn-on, and 80 V/µs dV/dt immunity in an SMT-optimized package-making it the only option meeting stringent timing and noise immunity requirements in modern GFCI/AFCI IC-based designs.

Availability

X0115MUF is available at Aetrix Electronics and suitable for ground-fault interrupters, arc-fault detectors, and overvoltage crowbar circuits requiring stable component supply across industrial, residential, and appliance OEM programs.

Supply support for X0115MUF 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, specializing in power management, analog, and discrete devices for industrial, automotive, and consumer markets.

The X0115MUF belongs to ST's sensitive-gate SCR family, engineered specifically for high-reliability, low-power-triggered protection functions in AC line monitoring and fault-interrupting systems.

FAQ

What is the maximum junction temperature for continuous operation?

The X0115MUF supports continuous operation up to 125 °C junction temperature, validated per absolute maximum ratings in DS13078 Rev 4. Derating begins above this limit, and thermal design must maintain T_j ≤ 125 °C using R_th(j-l) = 15 °C/W and adequate PCB copper area.

Can the X0115MUF be driven directly from a microcontroller GPIO?

Yes-its 30–150 µA gate trigger current and ≤0.8 V gate threshold allow direct drive from most 3.3 V or 5 V MCU GPIOs with a series resistor (e.g., 10 kΩ for 330 µA peak). No external transistor buffer is required for standard logic-level triggering.

Does the SMBflat-3L package meet RoHS and halogen-free requirements?

Yes-the X0115MUF SMBflat-3L package is lead-free and complies with RoHS Directive 2011/65/EU and ST's ECOPACK2 environmental standard, including halogen-free epoxy formulation per IEC 61249-2-21.

How does the 3.4 mm creepage distance translate to system-level safety certification?

The 3.4 mm creepage meets UL 840 requirements for 250 V functional isolation at Pollution Degree 2, enabling use in Class II insulated GFCI/AFCI modules without additional slotting or conformal coating-reducing bill-of-materials and assembly cost.