Company: Power Integrations
Category: Power Product of the Year
Launched by Power Integrations in 2020, the MinE-CAP is a game-changer for compact chargers and adapters. MinE-CAP™ is a new type of IC for high power density universal input AC-DC converters. This new device enables a reduction in adapter size of up to 40% by halving the size of the high-voltage bulk electrolytic capacitors required in offline power supplies. MinE-CAP ICs also dramatically reduce in-rush current, making NTC thermistors unnecessary, increasing system efficiency and reducing heat dissipation. Applications include smart mobile chargers, appliances, power tools, lighting and automotive.
Electrolytic capacitors are physically large, occupy a significant fraction of the internal volume and often constrain form factor options, particularly minimum thickness, of adapter designs. MinE-CAP IC allows the designer to use predominantly low voltage rated capacitors for a large portion of the energy storage, which shrinks the volume of those components linearly with voltage. USB PD has driven a major market push towards small 65 W chargers and many companies have concentrated on increasing switching frequency to reduce the size of the flyback transformer. MinE-CAP provides more volume saving than doubling the switching frequency, while actually increasing system efficiency.
MinE-CAP leverages the small size and low RDSon of Power Integrations’ PowiGaN™ gallium nitride transistors to actively and automatically connect and disconnect segments of the bulk capacitor network depending on AC line voltage conditions. Designers using MinE-CAP select the smallest high-line rated bulk capacitor required for high AC line voltages and allocate most of the energy storage to lower voltage capacitors that are protected by the MinE-CAP until needed at low AC line. This approach dramatically shrinks the size of input bulk capacitors without compromising output ripple, operating efficiency, or requiring redesign of the transformer.
Conventional power conversion solutions reduce power supply size by increasing switching frequency to allow the use of a smaller transformer. MinE-CAP IC achieves just as significant overall power supply size reduction while using fewer components and avoiding the challenges of higher EMI and the increased transformer/clamp dissipation challenges associated with high-frequency designs.
MinE-CAP ICs work for all locations, including those that require engineers to design for wide-ranging input voltages that necessitate expensive high-voltage capacitors. MinE-CAP dramatically reduces the number of high-voltage storage components and shields lower voltage capacitors from wild mains voltage swings, substantially enhancing robustness while reducing system maintenance and product returns.
Housed in the miniature MinSOP-16A package, the new devices work seamlessly with Power Integrations’ InnoSwitch™ family of power supply ICs with minimal external components.
To support designers in integrating MinECap into their latest designs, Power Integrations made two initial design example reports freely available on its website. The first describes a 65W USB PD 3.0 power supply with 3.3 V – 21 V PPS output for mobile phone or laptop chargers, and the other describes a 60W USB PD 3.0 power supply for USB PD/PPS power adapters. In each of the initial design examples, the MinECap devices are paired with Power Integrations’ InnoSwitch3-Pro PowiGaN ICs.