原创 The difference between dm9161 and dm9161a

I design a RM9200 board, use at91rm9200dk as a reference. when plug a 100base-t cable to the board it seems can't link to the network. every time I use tftp to try to get a binary from server. u-boot print:

MII initalization error. nothing can be recieved. it seems something was wrong with the PHY. in the demo a dm9161 used. but I use a dm9161a instead. try to update driver of dm9161 in u-boot. it doesn't help yet.

compare reference design of dm9161 and dm9161a from DAVCOM. I found 2 deferences:

1. AVDD at dm9161 is a 3.3V input. dm9161a have a build in LDO convert 3.3v to 2.5v and supply the AVDD.

2. 10/100base-t rx the common pole must power with AVDD.

after update like above, the dm9161a can work correctly.