STMicroelectronics X0115ML

Overview

X0115ML from STMicroelectronics is a sensitive-gate silicon-controlled rectifier (SCR) thyristor rated for 0.8 A RMS on-state current and 600 V repetitive peak off-state voltage, with gate trigger current spanning 30–150 µA. It operates in SOT23-3L package and is engineered for low-power triggering in ground-fault and arc-fault circuit interrupters where gate drive current is severely constrained.

For engineers reviewing the X0115ML datasheet, X0115ML pinout, X0115ML application, or X0115ML equivalent, this device serves as a compact, UL-840-compliant 120 V functional insulation solution requiring precise dV/dt immunity, low IGT sensitivity, and surge robustness up to 750 V in space-constrained protection circuits.

Technical Context

The X0115ML implements a planar passivated SCR structure optimized for high static dV/dt immunity (≥80 V/µs at 125 °C) and stable latching behavior under variable gate-cathode resistance. Its 540 mΩ dynamic on-state resistance and 1.06 V threshold voltage at 125 °C support efficient conduction with minimal thermal rise in intermittent crowbar applications.

Triggering relies on a narrow, temperature-stable gate current window (30–150 µA), enabling direct interface with microcontroller GPIOs or low-current optocouplers without external amplification. The device sustains non-repetitive surges of 7.6 A (8.3 ms) and maintains functional insulation at pollution degree 2 via 1.1 mm creepage in its SOT23-3L footprint.

Key Specifications

Pinout & Package

SOT23-3L package: 3-terminal surface-mount device with anode (A), cathode (K), and gate (G) terminals; lead-free, halogen-free, UL94 V0 compliant epoxy; 0.89–1.25 mm height; 2.75–3.04 mm length; 1.20–1.75 mm width; 0.85–1.05 mm pin pitch.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar sensitive-gate SCR applications.

Compared with MCR106-6 and VS-ST015S06, the X0115ML delivers superior space efficiency, tighter IGT control, and better thermal coupling-making it optimal for automated SMT production of GFCI/AFCI modules where footprint and gate sensitivity are critical.

Availability

X0115ML is available at Aetrix Electronics and suitable for ground-fault circuit interrupters, arc-fault circuit interrupters, and capacitive ignition systems requiring stable component supply across high-mix, low-volume industrial production runs.

Supply support for X0115ML 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 devices, sensors, and analog ICs for industrial, automotive, and consumer markets.

The X0115ML belongs to ST's sensitive-gate SCR family, developed specifically for compact, low-power AC protection circuits where gate drive capability is limited and functional insulation must be achieved without additional isolation components.

FAQ

What is the maximum junction temperature for continuous operation of the X0115ML?

The X0115ML has an operating junction temperature range of –40 °C to +125 °C. Continuous operation at +125 °C is permitted only when average on-state current remains ≤0.5 A (IT(AV)) and thermal resistance to ambient is maintained below 350 °C/W via adequate PCB copper area, per Figure 4 in DS13776 Rev 4.

Can the X0115ML be used in 230 VAC systems?

Yes-the 600 V VDRM rating provides sufficient margin for 230 VAC RMS (325 V peak) plus transient overvoltages defined in IEC 61000-4-5. Its 750 V non-repetitive surge rating further accommodates line spikes up to ±1 kV, making it suitable for European and Asian mains-connected protection designs.

Does the X0115ML require a gate resistor for reliable triggering?

No external gate resistor is required for basic triggering due to its 30–150 µA IGT range and 5 mA maximum holding current. However, a 1 kΩ series resistor is recommended when driving from CMOS outputs to limit peak gate current during fast edges and improve noise immunity per Figure 9 in the datasheet.

How does the SOT23-3L package meet UL-840 functional insulation requirements?

The SOT23-3L package achieves 1.1 mm creepage distance between anode and cathode terminals, satisfying UL-840's minimum requirement for 120 V functional insulation at pollution degree 2. This eliminates need for slotting or conformal coating in GFCI/AFCI PCB layouts, as confirmed in ST's package documentation DS13776 Rev 4 section 2.1.