We have a product base on W7100A. We followed closely your recommendations in iMCU7100EVB Rev 1.1. Now we are facing with a problem of noise. We noticed that in some of our products there are noises from TCP line (8 modules among 90 modules).
Please help us in troubleshooting this problem.
We provide below parameters of components that are different with the schematic in iMCU7100EVB Rev 1.1.
In our schematic:
CP5 =47 uC/ 16V
CP7= 22 uC/16V
FB5= two inductors 4.7 uH (in parrallel) (We noticed that if we touch the point after FB5 by our bare hand, almost always W7100A resets. Interesting, why?).
FB1= two inductors 4.7 uH (in parrallel)
(Note: FB1=two inductors (0805) 4.7uH in parrallel, each has current rating:50mA. I personally think that this current rating is too low, but I have not found any heat from the inductors. So maybe there is no problem in using them) (in Vietnam it’s hard to find exactly components that we need, so sometimes we use components with different electrical characteristics).
iMCU7100EVB_Rev1.1_Schematic.pdf (39.3 KB)