LMR14020-Q1: Need some suggestions to improve its gain and phase margin

Hi Andy

Ok I have let customer reduce the C2063 while the cross frequency at 0dB point is a little bit low, could you please help to check what other components could be modified to improve the cross frequency? Thank you.

Hi Andy

Update the test result, customer has passed the loop test under 1A and 2A load but when the load is changing to light load 0.2A, there will still be some problems with the cross frequency at 0dB point that the cross frequency is still low, what else suggestions could use when customer using light load? Thank you.

Hi Andy

Update the test result, customer has passed the loop test under 1A and 2A load but when the load is changing to light load 0.2A, there will still be some problems with the cross frequency at 0dB point that the cross frequency is still low, (about 1~5% switch frequency) 

What else suggestions could use when customer using light load? Thank you.

Converter enters PFM mode at 0.2A load, switching freq will drop and the loop works at hysteresis mode, so loop response is quite different from peak current mode at CCM condition.

B R

Andy

Thanks Andy, so I would like to ask that is it necessary for customer to do the light load loop response? Or how to check when in PFM mode the loop test is OK or not, thank you.

Hi Andy,

To LMR14020Q1 (2A max output), do you think 450mA will enter the PFM mode? Is there a typical or experienced percentage of max output for the buck enter from CCM mode into the PFM mode? Thank you.