DESCRIPTION
The SC4905A/B is a 10 pin BICMOS primary side voltage mode controller for use in Isolated DC-DC and off-line switching power supplies. It is a highly integrated solution, requiring few external components. The device features a high speed oscillator with integrated feed forward compensation, accurately programmable maximum duty cycle, voltage mode of operation, line voltage monitoring, supply UVLO, low start up current, low voltage current limit threshold and user accessible reference. The SC4905A/B device operates at a fixed frequency, highly desirable for Telecom applications. FEATURES
a separate SYNC pin which simplifies synchronization to an external clock. Feeding the oscillator of one device to the SYNC of another forces biphase operation (180 degrees apart) which reduces input ripple and filter size. The SC4905A has a turn-on threshold of 4.5V and High Performance Voltage Mode PWM Controller PRELIMINARY FEATURES
K Operation to 1MHz K Accurate programmable maximum dut...
Semtech Corporation
