STMicroelectronics ACS402-5SB4

Overview

ACS402-5SB4 from STMicroelectronics is a quad high-voltage AC line switch array in DIP-20 package, integrating four bidirectional thyristor-based switches with on-chip clamping and gate-level shifter drivers. Each switch supports 500 V blocking voltage, 600 V clamping voltage, 0.2 A RMS per switch (0.4 A total array), and triggers with negative gate current <10 mA. It is used for static AC on/off control of low-power inductive/resistive loads in home appliances.

For engineers reviewing the ACS402-5SB4 datasheet, ACS402-5SB4 pinout, ACS402-5SB4 application, or ACS402-5SB4 equivalent, key selection criteria include IEC61000-4-5 transient ruggedness, integrated overvoltage protection, direct microcontroller interface without external snubbers, and thermal derating at elevated ambient temperatures.

Technical Context

The ACS402-5SB4 implements four independent AC switches based on the ASD™ thyristor architecture, each featuring integrated avalanche clamping (VCL = 600 V) and gate-level shifting to isolate digital controllers. It operates in full-cycle AC conduction mode with no zero-crossing detection.

Each switch turns off via natural current zero crossing and sustains turn-off energy up to ~20 mJ using internal clamping diodes. Gate triggering requires sourced negative current (IGT < 10 mA at 25°C), enabling direct drive from MCU GPIOs through series resistors - no external driver ICs or isolation components needed.

Key Specifications

Pinout & Package

DIP-20 plastic dual-in-line package with 10 pins unconnected (1, 3, 5, 7, 9, 12, 14, 16, 18, 20). Pin 11 is COM (common reference to neutral); pins 2, 4, 6, 8 are G1–G4 (gate inputs); pins 13, 15, 17, 19 are OUT1–OUT4 (switch outputs).

Key Features

Applications

Equivalent & Alternatives

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

Compared with ACS108-6SN and TLP362G, the ACS402-5SB4 delivers higher integration (four switches + drivers + clamping in one DIP-20), eliminates external components for IEC61000-4-5 compliance, and supports higher per-channel current - making it optimal for cost- and space-sensitive appliance control boards.

Availability

ACS402-5SB4 is available at Aetrix Electronics and suitable for washing machine control, dishwasher valve actuation, refrigerator defrost systems, and cookware fan & lamp control requiring stable component supply and long-term industrial availability.

Supply support for ACS402-5SB4 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, mixed-signal, power, and microcontroller products for industrial, automotive, and consumer markets.

The ACS family targets appliance-grade AC load switching, emphasizing integration, surge resilience, and direct MCU interfacing - specifically engineered to replace discrete triac/optocoupler/surge-protection combinations in white goods.

FAQ

What is the maximum ambient temperature for full 0.4 A total array current?

The ACS402-5SB4 supports 0.4 A total RMS current only when ambient temperature (Tamb) is ≤90°C, as specified in Figure 6 of the datasheet. At Tamb = 110°C, the per-switch limit drops to 0.2 A, reducing total usable current to 0.2 A unless duty cycling or heatsinking is applied.

Can ACS402-5SB4 drive a 230 VAC, 60 W incandescent lamp?

Yes - a 60 W lamp draws ~0.26 A at 230 VAC, exceeding the 0.2 A per-switch RMS rating. However, cold filament resistance causes high inrush current (dI/dt up to 100 A/µs), which the device handles per Figure 4. Derating to 0.18 A RMS is recommended for long life; use only with adequate thermal margin and no sustained overload.

Does ACS402-5SB4 require external snubber circuits for inductive loads?

No - the integrated clamping diode limits VCL to 600 V and safely dissipates up to ~20 mJ of turn-off energy (e.g., from 10 H solenoids), eliminating external RC snubbers for loads within its 0.2 A RMS rating and Table 1 commutation groups.

How is gate triggering polarity implemented in practice?

Gate triggering requires negative current flowing *out* of G1–G4 pins. In practice, connect each gate to MCU GPIO via a series resistor (e.g., 220 Ω), and drive the GPIO low to sink current from the internal gate driver - no external pull-down or active sourcing is needed.