AC Switches

Product selector
CAD Resources
Tools & Software
  • Our ACST series are over-voltage protected triacs that protect themselves by folding back and leading current into the load when subjected to an overvoltage.
    This feature and the well-dimensioned 10 to 35 mA gate versions as well as its 800 V, 4 to 16 A range make this series ideal for appliances or equipment plugged in 24/7.
  • Featuring 800 V and 5 mA gate rated devices, our ACS™ AC switches, also with overvoltage protection, are smaller devices with highly inductive load switching capabilities for home and irrigation appliances including solenoid actuators and pumps.

AC Switches belong to our STPOWER family.



eDesignSuite is a comprehensive set of easy-to-use design-aid utilities ready to help you streamline the system development process with a wide range of ST products.

Thermal-electrical Simulators for Components

Choose design tool:

AC Switches Simulator

Select ratings and application waveforms
Get junction temperature and blocking voltage graphs
Search and sort suitable devices

Rectifier Diodes Simulator

Select ratings and application waveforms
Estimate power losses
Search and sort suitable devices


Supports long mission profiles
Provides power loss and temperature graphs
Helps define heatsink thermal properties

Twister Sim

Help select the right ViPOWER Automotive power device
Supports load-compatibility, wiring harness optimization, fault condition impact and diagnostic analysis
Supports various PCB configurations

TVS Simulator

Specify system ratings and surge waveform
Search and sort suitable devices