UCC3810

UCC2810 UCC3810 www.ti.com SLUS162D – FEBRUARY 1999 – REVISED FEBRUARY 2007 DUAL CHANNEL SYNCHRONIZED CURRENT-MODE PWM FEATURES Single Oscillator Synchronizes Two PWMs 150-µA Startup Supply Current 2-mA Operating Supply Current Operation to 1 MHz Internal Soft-Start Full-Cycle Fault Restart Internal Leading-Edge Blanking of the Current Sense Signal 1-A Totem Pole Outputs 75-ns Typical Response from Current Sense to Output 1.5% Tolerance Voltage Reference N PACKAGE (TOP VIEW) SYNC CT RT FB1 COMP1 CS1 OUT1 GND 1 2 3 4 5 6 7 8 16 VCC 15 REF 14 ENABLE2 13 FB2 12 COMP2 11 CS2 10 OUT2 9 PWRGND DESCRIPTION The UCC3810 is a high-speed BiCMOS controller integrating two synchronized pulse width modulators for use in off-line and dc-to-dc power supplies. The UCC3810 family provides perfect synchronization between two PWMs by usin g the same oscillator. The oscillator’s sawtooth waveform can be used for slope compensation if required. Using a toggle flip-flop to alternate between modulators, the UCC3810 ensures that one PWM does not slave, interfere, or otherwise affect the other PWM. This toggle flip- flop also ensures that each PWM is limited to 50% maximum duty cycle, insuring adequate off-time to reset magnetic elements. This device contains many of the same elements of the UC3842 current mode controller family, combined with the enhancements of the UCC3802. This minimizes power supply parts count. Enhancements include leading edge blanking of the current ...