STMicroelectronics ACS102-6T1

Overview

ACS102-6T1 from STMicroelectronics is a transient-protected AC line switch (ACS™) designed for direct microcontroller-driven AC ON/OFF control of low-power inductive or resistive loads. It delivers 0.2 A RMS on-state current, 600 V blocking voltage, and integrated overvoltage crowbar clamping with V_CL ≥ 650 V at 125 °C. Used in appliance valves, solenoids, and door locks where surge immunity and snubberless operation are critical.

For engineers reviewing the ACS102-6T1 datasheet, ACS102-6T1 pinout, ACS102-6T1 application, or ACS102-6T1 equivalent, key selection criteria include gate-trigger polarity (negative current), static dV/dt > 300 V/µs at 125 °C, I²t = 0.38 A²s fusing limit, thermal resistance R_th(j-l) = 150 °C/W (SO-8), and SO-8 package compatibility with shared cooling pads.

Technical Context

The ACS102-6T1 implements an Application-Specific Device (ASD) architecture combining a bidirectional thyristor switch with integrated gate-level shifter and crowbar overvoltage protection. Its negative-gate-triggering logic isolates digital controllers from mains-referenced switching paths while enabling direct MCU interface via a single series resistor.

It operates in quadrants II and III only, with latching current ≤ 25 mA and holding current ≤ 20 mA at 25 °C. The clamping mechanism activates during inductive turn-off or IEC 61000-4-5 transients (up to 2 kV peak), dissipating energy in the avalanche structure without external components.

Key Specifications

Pinout & Package

ACS102-6T1 uses the SO-8 surface-mount package with exposed tab for thermal conduction and common COM connection across multiple ACS devices on one cooling pad. Pin 1 is marked by notch or dot; orientation follows JEDEC MS-012.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar AC line switching applications.

Compared with ACS102-6TA and ACS108-6T1, the ACS102-6T1 uniquely balances minimal footprint, snubberless inductive drive, and thermal scalability via shared COM tab-making it optimal for space-constrained, high-reliability appliance control modules.

Availability

ACS102-6T1 is available at Aetrix Electronics and suitable for appliance valve control, industrial door lock actuation, dispenser motor drive, and small solenoid control in HVAC requiring stable component supply across production lifecycles.

Supply support for ACS102-6T1 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 sensing solutions for industrial, automotive, and consumer markets.

The ACS™ family was developed specifically for snubberless, microcontroller-direct AC switching in white goods and industrial controls-emphasizing robustness against inductive turn-off overvoltage and IEC 61000-4-5 transients.

FAQ

What is the correct gate drive configuration for ACS102-6T1?

The ACS102-6T1 requires a negative gate current-i.e., current must flow *out* of the G pin into the MCU GPIO (sinking mode). A series resistor (typically 2.2 kΩ for 5 V, 1.2 kΩ for 3.3 V) connects between GPIO and G, with COM tied to MCU ground reference. No pull-up or level shifter is needed.

Can ACS102-6T1 replace a mechanical relay in 230 VAC applications?

Yes-it replaces relays driving loads ≤ 0.2 A RMS (e.g., 50 W resistive or 30 VA inductive). Unlike relays, it offers silent operation, infinite cycle life, no contact bounce, and built-in IEC 61000-4-5 surge protection. However, it does not provide galvanic isolation, so system-level isolation must be maintained elsewhere.

Does ACS102-6T1 require a heatsink for 0.2 A continuous operation?

No heatsink is required at T_amb ≤ 60 °C with ≥40 mm² copper pour under the SO-8 tab. At 100 °C ambient, junction temperature remains within 125 °C limit (R_th(j-a) = 150 °C/W) with that copper area. For higher ambient or smaller copper, derating to 0.15 A RMS is recommended.

How does the crowbar overvoltage protection work during inductive turn-off?

When load current falls below holding current (I_H ≤ 20 mA), the device enters avalanche breakdown at clamping voltage V_CL ≥ 650 V. Energy stored in the inductance (½LI²) is dissipated safely within the silicon, limiting voltage rise and eliminating external snubbers. Conduction ceases at next zero-crossing.