Integrated flyback converter IC reduces component count in USB PD EPR power supplies
New InnoSwitch™5-Pro ac-dc converters from Power Integrations use a zero-voltage switching flyback topology and advanced synchronous rectification FET control to produce 95% efficiency, shrink the power supply and reduce component count.
Power Integrations has announced the release of the InnoSwitch5-Pro family of programmable flyback switcher ICs, which offer more than 95% efficiency in streamlined ac-dc converter designs. The new converters feature a novel secondary-side control scheme which can perform zero-voltage switching without a dedicated and costly additional high-voltage switch.
The new product features a 750 V or 900 V PowiGaN™ gallium nitride (GaN) primary switch, a primary-side controller, FluxLink™ isolated feedback, and a secondary controller with an I2C interface. It enables OEMs to realize designs for single- or multi-port USB Power Delivery (PD) adapters that are more compact and efficient. It supports the new USB PD extended power range (EPR) protocol.
The low conduction losses of the integrated GaN power switch enable power-system designers to implement very dense adapter layouts with far fewer components than asymmetric half-bridge (AHB) circuits or active clamp designs. A Power Integrations demonstration design for a 140 W/28 V USB PD adapter uses only 106 components in a system measuring just 4.2 in3.
The excellent efficiency of the InnoSwitch5-Pro allows designers to eliminate heat-sinks, heat spreaders and potting materials for thermal management, further reducing the size, weight, component cost and manufacturing complexity of their products. In addition, the flyback topology used by the InnoSwitch5-Pro ICs is easier to implement than AHB, and can operate from a universal mains supply with or without a PFC stage.