STMicroelectronics (ST), one of the world's top-ranked semiconductor companies, is enhancing the sustainability of personal computing products with its next generation of innovative technology. The new chip, called ST-ONE, will improve the energy efficiency of a variety of AC-DC adapters that are fully compliant with the USB-PD 3.1 standard, including laptop and smartphone chargers. The new adapters with ST-ONE will reduce CO2 emissions and plastic consumption.

The new ST-ONE chip can be used with ST's MasterGaN power output modules based on advanced gallium nitride (GaN) semiconductor technology, which provides significant power savings and reduces device size.

The ST-ONE chip is optimized for power control and recovers power that would normally be consumed as heat in conventional circuits. The product also simplifies circuit design and significantly reduces the number of power supply components, making this type of power supply more robust, more economical and more widely adopted throughout the market.

If each power supply were designed with ST-ONE energy recovery circuitry, which would increase the energy efficiency of power adapters by at least 1 percent, the world could save approximately 93 trillion watt-hours of power, equivalent to the output of 15 nuclear power plants," said Domenico Arrigo, general manager of ST's Industrial and Power Conversion Division. "In addition, if 1 billion chargers worldwide used our technology, 200,000 tons of plastic and raw materials could be saved."

The reduction in consumables such as plastic is achieved by increasing what is called power density, with high power density allowing smaller components to handle greater power output. High power density also reduces recycling and environmental costs.

At the recent Embedded World embedded electronics exhibition in Nuremberg, Germany, ST presented the EVLONE65W, a 65-watt USB-C laptop power adapter reference design that is the same size and weight as a standard 20-watt smartphone charger ( 37 cubic centimeters, less than 70 grams), achieving an ultra-high power density of cubic centimeters and less than 70 grams, achieving an ultra-high power density of over 1.8 watts per cubic centimeter.

Detailed technical information

The ST-ONE is optimized for new non-complementary active clamp flyback topology designs to support higher power, with higher efficiency performance above 65W than other flyback topologies such as quasi-resonant flyback. The chip is the world's first digital power controller to integrate a programmable offline power controller based on the Arm® Cortex®-M0+ core, a high-voltage start-up circuit, a synchronous rectifier controller and a USB-powered (USB-PD) circuit in a single package.

The ST-ONE includes all the peripherals needed to control power conversion, and the USB-PD communication is located in the secondary circuit and provides enhanced current isolation to allow the primary and secondary circuits to communicate while meeting electrical safety requirements. Also available with the MasterGaN, which integrates advanced wideband transistor power tubes and optimized GaN drivers, the adapter can operate at higher switching frequencies, allowing the use of smaller sized magnetic components and maximizing power density.

The ST-ONE is equipped with 64KB embedded flash memory for designers to customize the USB-PD protocol and set power conversion parameters, and the ST-ONE controller flash memory is preloaded with USB-PD 3.1 PPS certified firmware, providing a total solution for users to design standard power supplies.