Primary-Side-Regulation PWM Controller (PWM-PSR)

This third-generation Primary-Side-Regulation (PSR)and highly integrated PWM controller provides severalfeatures to enhance the performance of low-powerflyback converters. The proprietary topology,TRUECURRENT®, of FAN103W enables precise CCregulation and simplified circuit for battery chargerapplications. A low-cost, smaller and lighter chargerresults as compared to a conventional design or a lineartransformer. To minimize standby power consumption, theproprietary green-mode function provides off-timemodulation to linearly decrease PWM frequency underlight-load conditions. This green mode assists the powersupply in meeting the power conservation requirement. By using the FAN103W, a charger can be implementedwith few external components and minimized cost. Atypical output CV/CC characteristic envelope is shownin Figure 1.