High-efficiency quasi-resonant PFC IC with GaN switch

Power Integrations has launched the HiperPFS-5 family of PFC ICs with an integrated 750 V PowiGaN gallium-nitride switch. With an efficiency of up to 98.3%, the new ICs provide up to 240W with no heat sink and can deliver a power factor of better than 0.98. The ICs are excellent for high-power USB PD adapters, TVs, game consoles, all-in-one computers and appliances.

Commented Edward Ong, senior product marketing manager at Power Integrations: "With OEMs and after-market suppliers racing to create the fastest, smallest, most versatile USB PD chargers for mobile devices, HiperPFS-5 ICs give engineers a critical advantage. We have combined our proprietary PowiGaN switch with a quasi-resonant, variable-frequency discontinuous mode boost PFC topology. By pairing HiperPFS-5 ICs with our new HiperLCS2 chipset or our InnoSwitch™4-CZ active-clamp flyback ICs, designers can easily beat even the most aggressive efficiency regulations while cutting the bill of materials by half and achieving extremely attractive form factors for ultra-fast chargers."

The device's innovative QR DCM control technique alters the switching frequency over output load, input line voltage and input line cycle. QR DCM control assures low switching losses and enables the use of a low-cost boost diode. The variable-frequency engine reduces boost inductor size by more than 50% compared to conventional CRM boost PFC circuits. Low switching and conduction losses – which are reinforced still further by the PowiGaN switch – together with lossless current sensing mean that the ICs provide high efficiency over the complete load range, with efficiency rising as high as 98.3%. The ICs offer a PF higher than 0.98 at full load. An innovative PFE compensates for input filter capacitance at light loads, maintaining a high PF of 0.96 even at a 20% load. No-load power consumption is just 38mW.

Other benefits accrue due to the robust 750V PowiGaN switch. The mains power can be volatile in many locations worldwide, often leading to over-voltage failure of power supply components. The ICs maintain a high-power factor up to 305VAC and can operate continuously at up to 460VAC during line swells. Additionally, it incorporates the company's automatic X-capacitor discharge (CAPZero) function, including the required redundant pins to satisfied safety regulations and high-voltage self-start-up – all in a low-profile, InSOP-T28F SMD power package. Exposed cooling pads provided in the package are at source potential, offering effective cooling and simplifying the EMI solution. Digital line-peak-voltage detection guarantees robust performance, even in the presence of distorted input from uninterruptable power supplies or generators.