Design Win

Insulated control of three AC loads up to 1 kW

Solution Description

This solution implements insulated control of three AC loads up to 1 kW (230 Vrms) with Triacs and AC switches instead of relay solutions, offering improved safety, size and efficiency performance as well as greater design flexibility in any number of residential appliances, including micro-wave ovens, cookers, ovens, soya-milk makers, air-conditioners, fridges, washing machines, dish washers, printers, water-heaters, heaters, etc.

It features the T1635T-8FP, ACST310-8B and ACS108-8TN AC switches for the management of AC loads such as AC universal motors, lamps and valves, and the VIPER16HD AC-DC converter implemented in a Flyback circuit to provide the appropriate voltages and currents to the main components.

The digital control block with STM32F0 microcontroller generates the control signals for the three AC switches to drive three different loads in on/off mode and/or phase control mode according to final application requirements.

  • Key Product Benefits

    T1635T-8FP - 16A Triac

    This 16 A Snubberless™ Triac can be used for the on/off or phase angle control function in general purpose AC switching where high commutation capability is required. It allows more compact designs with reduced BOMs as snubber circuits are not required.

    ACS108-8TN - 0.8A AC switch

    This overvoltage protected AC switch (ACS™) featuring can control a load up to 0.8 A. It includes an overvoltage crowbar structure to absorb the inductive turn-off energy, and a gate level shifter driver to separate the digital controller from the main switch.

    ACST310-8B - 3A AC switch

    This overvoltage protected AC switch (ACS™), built with A.S.D.® technology, can control a load up to 3A. It includes a high voltage clamping device able to absorb the inductive turn-off energy and withstand line transients. It can be drive with a low gate current to be activated (IGT max. 10 mA).


    VIPER16 - Aux bias winding free Converter

    The device is an off-line converter with an 800 V avalanche ruggedness power section, a PWM controller, user-defined overcurrent limit, protection against feedback network disconnection, hysteretic thermal protection, soft start up and safe auto restart after any fault condition. It can power itself directly from the rectified mains, eliminating the need for an auxiliary bias winding.

    STM32F030 - Low-cost high-performance MCU

    This microcontroller with 48 MHz ARM Cortex-M0 CPU and 16 Kbytes Flash is a very low cost device with a full set of performance peripherals such as fast 12-bit ADC, advanced and flexible timers, calendar RTC and communication peripherals, including I²C and USART.

  • All Features

    • insulated control of three different AC switches used to drive AC loads up to 1 kW (230 Vrms) for residential appliances
    • Three control modes available thanks to STM32 Nucleo-64 firmware (continuous or pulse gate current, timer option and phase control)
    • Input voltage range: 90 V
    • Operating temperature: 0 °C to 60 °C
    • 5 V and 3.3 V insulated power supply
    • Low standby power losses (< 300 mW)
    • Criteria A @ 2 kV IEC 61000-4-4
    • Criteria B @ 4 kV IEC 61000-4-4
    • RoHS compliant