STMicroelectronics TS110-8A1

Overview

TS110-8A1 from STMicroelectronics is a sensitive gate silicon-controlled rectifier (SCR) designed for circuit breaker protection in GFCI, AFCI, and RCBO applications. It delivers 1.25 A RMS on-state current, 800 V repetitive peak off-state voltage, and ultra-low 100 µA triggering gate current, enabling reliable latching with minimal drive energy in space-constrained safety devices.

For engineers reviewing the TS110-8A1 datasheet, TS110-8A1 pinout, TS110-8A1 application, or TS110-8A1 equivalent, this device is selected for high dV/dt immunity (200 V/µs), robust 1250 V non-repetitive surge withstand, and TO-92 GAK pinout compatibility in ground-fault and arc-fault detection circuits.

Technical Context

The TS110-8A1 operates as a crowbar-type overvoltage protector: it triggers into conduction during IEC 61000-4-5 line surges (e.g., 1.2/50 µs, 27 A peak), safely diverting transient energy through the load without external clamping. Its low IGT (100 µA max) and high dV/dt immunity (200 V/µs at Tj = 125 °C) ensure stable blocking under electrical fast transients while avoiding false tripping.

It features a thermally optimized TO-92 package with GAK pinout (Gate-Anode-Cathode), junction-to-lead thermal resistance of 65 °C/W, and operation up to 125 °C junction temperature-enabling direct integration into thermally constrained PCB layouts in compact circuit breakers.

Key Specifications

Pinout & Package

TS110-8A1 is supplied in a lead-free, halogen-free TO-92 package (ECOPACK2 compliant) with GAK pinout configuration: Pin 1 = Gate, Pin 2 = Anode, Pin 3 = Cathode. Mechanical dimensions conform to ST's standard TO-92 outline (A = 1.35 mm, E = 12.70 mm).

Key Features

Applications

Equivalent & Alternatives

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

Compared with TS110-8A1, T110-8A1 demands stronger gate drive and offers lower surge ruggedness, while S4006L lacks crowbar functionality and requires additional protection circuitry-making TS110-8A1 uniquely suited for compact, self-protected, low-power circuit breaker designs.

Availability

TS110-8A1 is available at Aetrix Electronics and suitable for GFCI outlet modules, AFCI breaker panels, and RCBO dual-protection units requiring stable component supply, long-lifecycle support, and compliance with IEC 61000-4-4/5 immunity standards.

Supply support for TS110-8A1 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 analog, MCU, power, and sensor solutions for industrial, automotive, and consumer markets.

The TS110-8 series belongs to ST's high-reliability protection SCR product line, engineered specifically for self-protecting, low-power, high-immunity roles in residual-current and arc-fault circuit interrupters.

FAQ

What is the maximum allowable gate-cathode resistance for reliable triggering?

The datasheet specifies that reliable triggering is guaranteed with RGK ≤ 220 Ω at Tj = 25 °C. At elevated temperatures (125 °C), IGT increases, so RGK should be reduced to ≤ 150 Ω to maintain margin. Exceeding 220 Ω risks non-latching behavior under worst-case temperature and aging conditions.

Can TS110-8A1 replace a standard 400 V SCR in an existing GFCI design?

No-TS110-8A1 is not a drop-in replacement for generic SCRs. Its 800 V VDRM, 100 µA IGT, and crowbar surge response are purpose-built for modern safety standards. Substituting it for a 400 V part would require verifying gate drive compatibility, thermal layout, and surge test compliance per IEC 61000-4-5.

Does TS110-8A1 require a snubber network in GFCI applications?

No snubber is required for normal operation due to its 200 V/µs dV/dt immunity and built-in surge tolerance. However, a small RC snubber (e.g., 100 Ω + 100 pF) is recommended across A–K in high-noise industrial environments to suppress ringing above 10 MHz that could affect adjacent analog sensing circuits.

How does TS110-8A1 behave after a 1250 V surge event?

After a single 1250 V, 10 ms surge per IEC 61000-4-5, TS110-8A1 fully recovers blocking capability at the next AC zero-crossing. It retains all parametric specifications and can withstand ≥10 such events without degradation-confirmed by ST's qualification testing per JEDEC JESD22-A108.