Asking for the TPS51275B-1RUKR design suggestion
Hi Sir,
My customer would like design TPS51275B-1RUKR to generate 3.3V.
In order to improve the light load efficiency, so customer would like to replace the inductor L19 with lower DCR.
The inductor DRC will decrease from 2.2mohm to 1.1mohm.
Would you please review design provide your comment?
here is the schamtic and inductor spec.thanks for help!
BR,
SHH
Hi SHH,
A smaller DCR inductor may has little improvement for light load efficiency. What's customer's light load value? The inductor DCR power loss can be calculated as P=I*I*DCR, if I is small, DCR power loss will be small. Then switching loss may be the major power loss that affects light load efficiency.
Does customer care about audible noise? If not, they could use TPS51275C (Auto-Skip mode) instead of TPS51275B-1 (automatically enter Out-of-Audio mode). Auto-Skip mode reduces more switching loss and gets better efficiency at light load. Please refer to datasheet efficiency curve.
