Hi TI EE:
Tps54331DR 5V to 1.2V buck circuit as bellow and the load current is about 200mA,and this1.2V is for DSP&FPGA.
The test Waves are as bellow two figures:
C1:5V Vin C2:Vsense of TPS54331DR Pin5 C3:D1 VR C4:1.2V Vout
When Vsense is above 800mV,the TPS54331DR Still have pwm,that make 1.2V overshoot as high as 1.368V
The bellow fig shows that,Tps54331 first duty is 7.3us,after the first duty,Vout is 1.314V and Vsense is 868mV.But after the first duty,although Vsense is 868mV and the TPS54331DR still have 4 pwm ,that make the 1.2V overshoot even more serious.
Please help to explain the phenomenon and solve the overshoot problem ASAP.Tks!
Best Regards
Cheney_Sun
