NCP1225

NCP1225 is a low standby power Switch−Mode Power Supply, SMPS controller IC specially designed for low power AC−DC adapter applications. The NCP1225 operates in Discontinuous Conduction Mode (DCM) with Pulse Frequency Modulation (PFM) control scheme. PFM operation can provide high operating efficiency even at light loading conditions and the device itself takes extremely low operating current. With careful circuit design, low standby power down to 300 mW can be achieved for universal line input low power adapters. This specific feature can help the end products to comply with immediate and future international power saving regulations easily. An innovative feedback compensation scheme is integrated in NCP1225 to eliminate the expensive optocoupler in the feedback path. By only using simple auxiliary winding feedback, the regulator still can achieve good output voltage regulation usually not possible with common SMPS controller ICs without optocoupler. For even better regulation applications, optocoupler feedback can still be used in place. Additionally, value−added features as overvoltage protection, undervoltage lockout and overcurrent protection functions are also included. This NCP1225 controller is an ideal solution for low power adapters and mobile phone chargers. With all valuable features, this device is available in the tiny TSOP−5 package.