The UCC3810 is a high-speed BiCMOS controller that integrates two synchronous pulse width modulators for off-line and DC power supplies. The UCC3810 series provides perfect synchronization between the two pwm by using the same oscillator. The sawtooth waveform of the oscillator can be used for slope compensation if desired. Alternating between modulators using switching triggers, the UCC3810 ensures that one PWM does not override, interfere with, or otherwise affect the other.
Block diagram
This switching trigger also ensures that each PWM is limited to a maximum duty cycle of 50%, ensuring sufficient time to reset the magnetic element. The device contains many of the same elements as the UC3842 current mode controller family and combines the enhanced features of the UCC3802.This minimizes the number of power components. Enhancements include leading edge blanks for current detection signals, full cycle failure restarts, CMOS output drivers, and maintaining a low output even when the supply voltage is removed
Detailed block diagram