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CM6901T6
SLS (SRC/LLC+SR) Controller with 1 FM+2 PWMs
GENERAL DESCRIPTION
CM6901T6 is a SLS, SRC/LLC + SR resonant controller and it can operate at both SRC and LLC region with synchronous rectification to achieve high efficiency. Its unique features: FM + 2 PWMING modes. It is used for DC-DC conversion in offline application. Light load regulation is accomplished by transitioning the controller from frequency modulation mode into PWM mode. We call this is Light load PWMING function. When
ac turn off, bulk input voltage will drop. The switching frequency is below the highest resonant point
frequency fr1=1/ 2π LrCr ;Lr: resonant choke;
Cr: resonant cap . SR Ideal Diode PWMING for synchronous drivers is accomplished by comparing the voltage signal at the RSET pin to RTCT ramp.