Could these switcher ICs keep even the bean-counters happy?

22-09-2017 | By Paul Whytock

Anyone involved in the power supply sector knows it is a ferociously cost conscious business. Keeping the bean-counters happy at both the manufacturing and the purchasing end involves some clever technological developments and as usual it is the engineers who have to try and keep the corporate wallets happy.

Power supplies need to be small, efficient and cheap. So news of a switcher IC that can help power supply designers hit those criterion while simultaneously keeping the bean-counters happy is interesting stuff.

Enter the InnoSwitch3 family of integrated offline CV/CC flyback switcher ICs. So what makes these special? According to Power Integrations the company that developed them these devices achieve up to 94% efficiency across line and load conditions, they cut power supply losses by a further 25% and enable the development of compact-sized power supplies up to 65W without heatsinks. And that last attribute will certainly keep the bean-counters happy.

The InnoSwitch3 IC family is optimized into three application-specific series:

  • CE: Current External. Includes accurate CC/CV regulation with external output current sense for design flexibility. Targets compact single-voltage chargers, adapters, IoT and building automation.
  • CP: Constant Power. Good for USB Power Delivery (PD), rapid charging and other applications where a dynamic output voltage is required.
  • EP: Embedded Power. Features the family’s highest-rated MOSFET (725 V) and provides full line and load protection with multi-output cross-regulation for industrial applications and appliances.

These switcher ICs use an isolated digital communications technology, FluxLink, plus synchronous rectification, quasi-resonant switching and a secondary-side feedback sensing and control circuit. This says Power Integrations results in efficient, accurate, reliable power supply circuits without the need for optocouplers. The devices are CCC, UL and VDE safety-certified to bridge the isolation barrier, and the InSOP-24 package provides a low-profile, thermally efficient solution with extended 11.5 mm creepage and clearance between primary and secondary sides for reliability, surge and ESD robustness. The devices also have a whole load of protection features including lossless line overvoltage and under-voltage, output overvoltage, over-power, over-current and over-temperature protection, as well as output rectifier short-circuit protection.

So will the purchasing bean-counters be ecstatic about the pricing? InnoSwitch3 ICs target adapters and open-frame power supplies for consumer, computer, communication and industrial applications. InnoSwitch3-CP and InnoSwitch3-CE IC samples are available now, priced at $1.11 (CE) and $1.15 (CP), in 10,000-piece quantities. InnoSwitch3-EP parts will be available this November at $1.18 per 10,000-pieces.


By Paul Whytock

Paul Whytock is Technology Correspondent for Electropages. He has reported extensively on the electronics industry in Europe, the United States and the Far East for over thirty years. Prior to entering journalism, he worked as a design engineer with Ford Motor Company at locations in England, Germany, Holland and Belgium.