The LinkSwitch-II (LNK-II) IC simplifies constant current and constant voltage (CV/CC) converter design. This device eliminates the optocoupler and all secondary-side CV/CC controller circuitry. The lower schematic shows all the components, indicated by red dots, which are no longer necessary in CV/CC converters that are designed using the LinkSwitch-II. The upper right diagram shows a much simpler, LinkSwitch-II-based design. Designing with this IC simplifies the manufacturing process, increases yields, reduces inventory, and most importantly increases MTBF by more than 20%.