Hi, I am using MP2338 to generate 5V out of 10V. We are facing a strange Noise and Ripple behaviour on the output. The noise has almost 50-60mVpp or even higher, which is far above the desired ripple budget (ca. 20mVpp). Measurement principle is fine with short ground clip instead of the long probe ground lead. Attached you will find the schematics, which we are using for simulation.
Design is done according datasheet recommendations. Deviations from Datasheet recommendation is the resistor RT, which we have omitted in our design. The resistor is optional according datasheet.
Q1: May this be the root cause for increased ripple and noise, if we omit RT but populate a CFF with 330pF?
Q2: would it be sufficient to remove CFF capacitor in case RT is omitted?
I measured also the FB pin and there was also noise visible. In Simetrix/ Simplis simulation there is no difference visible if the RT is 10k or almost zero. However, this may be related to model limitations (?!)