Hello, Burst mode should only be engaged if the duty cycle is less than ton_min*fsw, which is programmed by Rtmin. You had mentioned that light load burst mode occurs between 1 – 3 A which is roughly 14.9% to 44.8% load. This should not trigger light load burst mode. If your output capacitor bank (Cout) is too small it could trigger burst mode when it should not. The following information can be used to check the Cout capacitor size. Light load burst mode is best used to improve standby power. I would recommend setting Rtmin to 10 k to the lowest value and see if this resolves the issue if the other two recommendations don’t work. If you want to improve light load efficiency I would use the DCM comparator to turn-off the SR FETs. There is a point where driving the SR FETs Ids^2*Rdson will not improve efficiency and driving the FETs will dissipate more power than it is worth. If (Qg*fsw +Ids^2*Rdson) is greater than Ids*Vbody_diode you should turnoff the SRs. Thankyou for your interested in power control devices from Texas Instruments. If you have a related question, please click the " Ask a related question " button in the top right corner. The newly created question will be automatically linked to this question. Regards,
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