The SC4806 is a double ended, high speed, highly integrated PWM controller optimized for applications requiring minimum space. The device is easily configurable for current mode or voltage mode operation and contains all the control circuitry required for isolated applications, where a secondary side error amplifier is used. Designed for simplicity, the SC4806 is fully featured and requires only a few external components. It features a programmable frequency up to 1MHZ, external programmable soft start, pulse-by-pulse current limit and over current protection for both voltage and current modes, as well as a line monitoring input with hysteresis to reduce stress on the power components. A ramp pin allows for slope compensation to be programmed by external resistors for current mode. This also allows for operation in voltage mode with voltage feed forward. A unique oscillator is utilized which allows two SC4806 to be synchronized together and work out-of-phase. This feature minimizes the input and output ripples, and reduces stress and size on input/output filter components. The outputs are configured for push-pull format, dead time between the 2 outputs is programmable depending on the size of the timing components. The SC4806 features a turn on threshold of 8 volts . The device is available at a MLP-12 package. |