This digest proposes a PWM density adjustment strategy for transient enhancement applied to processor power supply. The strategy optimizes PWM overlap during high-current steps, significantly reducing output voltage undershoot while maintaining current balance in each phase during transients. The transient performance of this strategy is independent of the power supply’s switching frequency during steady state, allowing the power supply to reduce frequency to improve power efficiency. Experimental results verified that, compared with existing products, during 1100 A/μs (0-250 A) current transient, the proposed strategy reduced the voltage undershoot from 132 mV to 76 mV. The dynamic performance remained the same when the prototype operated at a lower switching frequency, which improving the power efficiency by 4%.
