STMicroelectronics ACS302-5T3

Overview

ACS302-5T3 from STMicroelectronics is a three-channel high-voltage AC switch array in SO-20 package, integrating bidirectional thyristor-based switches with integrated clamping diodes and gate-level shifter drivers. It delivers 0.2 A RMS per channel (0.4 A total array), 500 V blocking voltage (VDRM/VRRM), 600 V clamping voltage (VCL), and triggers with negative gate current <5 mA. It is designed for direct microcontroller interfacing in appliance load control.

For engineers reviewing the ACS302-5T3 datasheet, ACS302-5T3 pinout, ACS302-5T3 application, or ACS302-5T3 equivalent, key selection criteria include per-channel RMS current rating, IEC61000-4-5 transient ruggedness, gate-trigger polarity, thermal derating at elevated ambient, and absence of external snubber requirements in inductive turn-off.

Technical Context

The ACS302-5T3 implements three independent ASD™ (Advanced Static Device) AC switches, each combining a high-voltage thyristor structure with an integrated avalanche clamping diode and gate-level shifter. Each switch operates in full-cycle AC conduction mode and turns off naturally at current zero-crossing when load current falls below holding current (IH ≈ 20–45 mA).

It features intrinsic overvoltage protection: low-energy transients are clamped at VCL = 600 V (typ.), while high-energy surges up to 2 kV (per IEC61000-4-5) cause controlled breakover without external components. Gate drive requires only a series resistor to sink negative current - no isolation or flyback protection needed.

Key Specifications

Pinout & Package

ACS302-5T3 is housed in a standard SO-20 surface-mount package (12.6 × 7.6 mm, 1.27 mm pitch), rated for lead-free soldering (260 °C, 10 s). Pin 1 is top-left corner (notch side), with pins numbered counter-clockwise.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ACS302-5T3TR, the tube-packaged ACS302-5T3 offers identical performance with manual or semi-automated placement flexibility; compared with ACS108-6SN, it delivers 3× channel density, 30% lower thermal resistance per switch, and reduced gate drive component count.

Availability

ACS302-5T3 is available at Aetrix Electronics and suitable for washing machine control modules, dishwasher valve systems, and refrigerator ice maker actuation requiring stable component supply, long-term lifecycle support, and IEC-compliant transient ruggedness.

Supply support for ACS302-5T3 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, MEMS, and automotive-grade ICs with vertical manufacturing and broad industrial qualification.

The ACS302 belongs to ST's ASD™ AC switch product line, engineered specifically for replacing electromechanical relays in white goods and industrial controls where snubberless inductive switching, IEC61000-4-5 compliance, and MCU-direct drive are mandatory.

FAQ

Can ACS302-5T3 drive a 230 VAC, 0.18 A solenoid directly without external snubber?

Yes. The integrated clamping diode limits turn-off voltage to 600 V (typ.) and safely dissipates up to ~20 mJ of inductive energy. Tested with 10 H loads and IEC61000-4-5 2 kV surges, it requires no external snubber for solenoids, valves, or micro-motors within its 0.2 A RMS rating.

What is the recommended gate resistor value for driving ACS302-5T3 from a 3.3 V MCU GPIO?

For reliable triggering at worst-case IGT = 5 mA and VGT ≤ 0.9 V, a 470 Ω resistor is recommended. This yields ~5.1 mA sink current at 3.3 V, stays within PG(AV) = 0.1 W limit, and provides margin against junction temperature rise affecting IGT (which increases at low Tj).

Does ACS302-5T3 meet IEC61000-4-5 Level 4 immunity requirements?

Yes. Its clamping and breakover behavior under the IEC61000-4-5 test circuit (R = 150 Ω, L = 5 µH, VPP = 2 kV) is explicitly validated in the datasheet. It withstands 10 pulses per polarity without degradation, satisfying Level 4 (2 kV line-earth, 1 kV line-line) for residential appliance applications.

How does thermal derating work when two switches operate simultaneously at 110 °C ambient?

Per Figure 6, at Tamb = 110 °C with two switches active, maximum IT(RMS) per channel drops to ~0.14 A. Total array current remains limited to 0.4 A (as rated), but simultaneous dual-channel operation at full 0.2 A requires Tamb ≤ 90 °C due to shared thermal resistance in SO-20 package.