Power converters for consumer products have always been extremely cost sensitive. In recent times, innovations in circuit simplification and integration have worked well to drive costs down, in spite of regulatory pressure to reduce energy waste by improved efficiency and minimized no-load power use. Powerful market forces have emerged which are dramatically increasing the complexity of power supplies – variable output voltage USB-PD, for example – and also increasing the required power density. In fact, due to fast charging and bigger batteries demanded by today’s large screen 5G cellphones, the power density needs of USB-PD adapters rival those of servers and other historically bleeding-edge application categories. In addition, the portability requirement and criticality of mobile devices in people’s lives means that failure is not an option, even in regions with highly variable mains power, high surge and fast transient exposure. Efficiency, robustness, and compactness requirements have combined to drive the first high volume use of high voltage GaN transistors, implementation of thermal foldback, and load-driven real time voltage and current adjustments with tens of millivolt and milliamp accuracy, all while maintaining a weather eye on affordability. This presentation details the market forces driving product developments and the response to those demands by semiconductor manufacturers.
