STMicroelectronics ACST210-8B

Overview

ACST210-8B from STMicroelectronics is a DPAK-packaged, overvoltage-protected AC switch (Triac) with 800 V blocking voltage, 2 A RMS on-state current, and 10 mA gate trigger current. It integrates crowbar-based overvoltage clamping (V_CL ≥ 850 V), delivers 500 V/µs static dV/dt immunity at 125 °C, and drives inductive loads like fans, pumps, and solenoids in appliance control circuits without external snubbers.

For engineers reviewing the ACST210-8B datasheet, ACST210-8B pinout, ACST210-8B application, or ACST210-8B equivalent, this device is selected for IEC 61000-4-4/4-5-compliant AC switching where high noise immunity, low gate drive burden, and self-protected turn-off transients are required in space-constrained DPAK layouts.

Technical Context

The ACST210-8B implements a planar Triac structure with integrated high-voltage clamping circuitry that activates during line transients to fold back into conduction-dissipating surge energy through the load rather than requiring external MOVs or RC snubbers. Its gate sensitivity (I_GT ≤ 10 mA) enables direct microcontroller interfacing via a single series resistor.

It operates across -40 °C to +125 °C junction temperature, sustains 2 kV non-repetitive peak mains voltage per IEC 61000-4-5, and maintains ≥500 V/µs dV/dt immunity even at maximum rated junction temperature-five to ten times higher than standard Triacs of comparable sensitivity.

Key Specifications

Pinout & Package

DPAK (TO-252) package: surface-mount, isolated tab, 3-pin configuration with exposed thermal pad. Pin 1 = Gate (G), Pin 2 = Main Terminal 1 / COM, Pin 3 = Main Terminal 2 / OUT.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ACS108-8SN and BTB04-800SL, the ACST210-8B uniquely combines DPAK surface-mount compatibility, self-protecting crowbar action, and 500 V/µs noise immunity-enabling smaller, more robust, and certification-ready AC switching without design compromises.

Availability

ACST210-8B is available at Aetrix Electronics and suitable for home appliance motor control, industrial solenoid actuation, and smart plug load switching requiring stable component supply and long-term production continuity.

Supply support for ACST210-8B 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, digital, and mixed-signal ICs for automotive, industrial, and consumer markets.

The ACST™/ACST2 product line targets solid-state AC switching in cost-sensitive, space-constrained applications where reliability under electrical stress-especially IEC 61000-4-4/4-5 transients-is critical.

FAQ

What is the maximum ambient temperature for continuous 2 A operation in DPAK?

At 2 A RMS, the ACST210-8B requires ≤75 °C ambient temperature on FR4 PCB with 0.5 cm² copper under tab (R_th(j-a) = 70 °C/W). Derating begins above this point; full 2 A is guaranteed only up to T_c = 110 °C case temperature per absolute maximum ratings.

Does ACST210-8B require a heat sink in typical appliance applications?

No external heat sink is required for 2 A loads when mounted on FR4 with ≥0.5 cm² of 35 µm copper under the tab. Thermal resistance is 4.5 °C/W junction-to-case, and typical power dissipation at 2 A is <1.5 W-sufficiently managed by PCB copper alone in most enclosed appliance designs.

Can ACST210-8B replace a mechanical relay in a 230 VAC, 1.5 A fan circuit?

Yes-it supports 2 A RMS with high inrush tolerance (8.0 A non-repetitive surge), handles inductive kickback via internal clamping, and provides >100,000 switching cycles without contact wear. Its 500 V/µs dV/dt immunity prevents false triggering from motor commutation noise.

Is the DPAK tab electrically isolated from the COM pin?

No-the DPAK tab is internally connected to the COM (MT1) terminal. Electrical isolation must be maintained externally via insulating thermal pads or non-conductive mounting hardware if COM is not at chassis ground potential.