Wide-creepage switcher IC targets 800-V automotive applications

Power Integrations has introduced a wide-creepage package option for its InnoSwitch™3-AQ flyback switcher IC for automotive applications.

A wide drain-to-source-pin creepage distance of 5.1 mm eliminates the need for conformal coating, making the switcher IC compliant to the IEC60664-1 standard in 800 V vehicles while simplifying manufacturing and increasing system reliability.

Mike Stroka, product marketing engineer at Power Integrations, said: “Automotive designers rely on the efficiency and low component count of high-voltage power supplies designed around InnoSwitch3-AQ ICs. The increased primary-to-primary creepage and clearance distance between the drain and source pins in the new package provides support for the next generation of EV bus voltages. The unique InSOP™-28G package from Power Integrations enables 1000-VDC to be provided to the primary side, while keeping all other pins safely isolated in pollution degree 2 environments.”

The 1700 V-rated CV/CC InnoSwitch3-AQ switching power supply ICs incorporate a silicon carbide (SiC) primary switch capable of delivering up to 80 W of output power. The highly integrated ICs reduce the number of components required to implement a power supply by as much as 50 percent, saving space, enhancing system reliability and mitigating component sourcing challenges. An increased drain-pin width is beneficial in withstanding high levels of shock and vibration, especially in eAxle automotive applications.

The new switcher IC members of the InnoSwitch3-AQ family will start up with as little as 30 V on the drain without external circuitry — which is critical for functional safety. Additional protection features include input under-voltage, output over-voltage and over-current limiting. Synchronous rectification and a multi-mode valley switching, discontinuous/continuous conduction mode (DCM/CCM) flyback controller deliver greater than 90 percent efficiency. Devices consume less than 15 mW at no-load. Target automotive applications include battery management systems, µDC-DC converters, control circuits and emergency power supplies in the main traction inverter. The new ICs also have improved functionality for remote on/off.

Samples of the 1700-V switcher IC are available now with full production in the first quarter of 2025.