Power Integrations announced the LinkSwitch™-4 family of CV/CC primary-side regulated (PSR) switcher ICs. The LinkSwitch-4 product family features an
advanced adaptive base and emitter switched drive scheme for bipolar junction transistor switches (BJTs) that substantially improves power conversion efficiency and eliminates reliability concerns due to secondary breakdown. The new family of devices targets chargers and adapters required to meet stringent new efficiency rules from the US Department of Energy (DoE) and European Code of Conduct (CoC), both of which are scheduled to come into force in January 2016. The new DoE rules, known as DoE-6, require efficiency compliance measurements to be taken at the end of the charger USB cable; LinkSwitch-4 exceeds the requirements while using a low-complexity Schottky diode secondary, even for high-current 1.5A and 2A smartphone chargers.
LinkSwitch-4 ICs incorporate a multimode PWM/PFM controller with a quasi-resonant switching strategy to maximize the efficiency, meet <30 mW no-load and at the same time maintain fast transient response. A high operating frequency of up to 65 kHz enables transformer size to be minimized, and the minimum peak current is fixed to improve transient load response. Power Integrations