Offline Flyback Switcher IC with Zero-Voltage Switching (ZVS) for 95 % Efficiency
Power Integrations has released the InnoSwitch5-Pro family of high-efficiency, programmable flyback switcher ICs. The single-chip switcher achieves over 95 percent efficiency with a novel secondary-side control scheme which achieves zero-voltage switching (ZVS) without a dedicated and costly additional high-voltage switch. The IC, which features a 750V or a 900V PowiGaN primary switch, primary-side controller, FluxLink isolated feedback and secondary controller with an I2C interface, is intended for single- or multi-port USB PD adapters. Applications are notebooks, high-end cellphones and other portable consumer products, including designs that require the USB PD EPR (Extended Power Range) protocol. For example, the company has demonstrated 140W / 28V USB PD adapters in 68,8 cm3 using 106 components. InnoSwitch5-Pro flyback switcher ICs feature lossless input line voltage sensing on the secondary side for adaptive DCM/CCM and ZVS control to maximize efficiency and simplify design across line and load. The ICs also feature a post-production tolerance offset to facilitate accurate output constant-current (CC) control of better than two percent to support the UFCS protocol. An efficiency of more than 95 percent allows designers to eliminate heat sinks, spreaders and potting materials for thermal management.
