Hi team,
We are testing the PMLKBUCKEVM, and we found that the actual output ripple current is much higher than the theoretical one, especially in the condition of Vin=24V, Vout=3.3V, fsw=250kHz. In that case, the theoretical output voltage is 633mA, but the actual one is 870mA. Could you pls help me to explain the reasons. Thanks a lot.
Hi Daniel,
The EVM is setup as follows:
L = 18µH, Cout = 220µF, Cin = 10µF.
The following waveform of SW and output ripple current was tested by vin=6v,vout=3.3V with different load current. Moreover, the fsw, L, Cin and Cout is the same as what were mentioned above.
Iload=0.5A
Iload=1.5A
Thanks a lot.
HI
even indutor value mark is 18uH, there still a real inductor with a bit lower inductance. for this waveform, the real inductance is around 14uH.
have you read the experiment book which also decribed the dynamic inductance?
