Below is power flow of my ADuM5201 design.
To reduce EMI from DC/DC inside ADuM5201, I made an attempt to add T filter just ahead of ADuM5201.
The result was as follows:
- Much heat was generated from LDO. It was hot.
- Data transfer via ADuM5201 was not correctly working.
Why does LDO generate much heat when a filter is added, especially an inductor?
There is no problem when ADuM5201 is removed out even though a filter is added.