First automotive-qualified high-voltage switcher ICs boosts efficiency

Power Integrations has added two new AEC-Q100 qualified, 1700V rated ICs to its InnoSwitch3-AQ family. The new devices are the industry's first automotive-qualified switching power supply ICs to incorporate a SiC primary switching MOSFET. Delivering up to 70W of output power, the new ICs are targeted for use in 600V and 800V battery and fuel-cell electric passenger vehicles and electric buses, trucks, and a wide range of industrial power applications.

Devices from the family are now available with a choice of cost-effective silicon, high-efficiency GaN and high-voltage SiC transistors, permitting designers to optimise their power solution across a broad range of consumer, computer, communications, industrial and automotive applications.

Peter Vaughan, director of automotive business development at Power Integrations, said: "800V batteries are becoming standard for EVs. Multiple vehicle systems are connected to this powerful electrical source, yet delicate electronic control circuits require a few volts for operation and communication. InnoSwitch devices allow the electronics to safely sip from the firehose of energy available on the main bus, using minimal board area and without wasting energy. Most exciting is the opportunity to dramatically simplify the emergency power supply for the main traction inverter, which may be called upon at a moment's notice to operate from any voltage between 30V and 1000V. Our SiC-based InnoSwitch3-AQ devices handle this vast range with incredible ease."

Offered in a compact InSOP-24D package, the new ICs use a FluxLink feedback link, giving reinforced isolation up to 5000VRMS for secondary-side control. FluxLink technology allows direct sensing of the output voltage, providing benefits such as accurate regulation and swift transient response. The circuit will start from 30V without external circuitry – critical for functional safety. Further protection features comprise input under-voltage, output over-voltage and over-current limiting.

The addition of synchronous rectification and a QR/CCM flyback controller attains greater than 90% efficiency, easily satisfying the strictest OEM demands. These new parts consume less than 15mW at no-load, excellent for lessening self-discharge in battery management systems.

The parts are also ideal for industrial markets, where the integrated solution substitutes discrete controller-plus-MOSFET designs, saving space, time and expense while increasing reliability in applications including renewables, industrial motor drives, battery storage and metering.