SNLA411 October 2022 DP83TC812R-Q1 , DP83TC812S-Q1 , DP83TC813R-Q1 , DP83TC813S-Q1
PHY can be placed into sleep by itself by bypassing the sleep negotiation by programming reg<0x0444> = 0x000C.
For this forced sleep to work, WAKE should be driven low and MDI lines should be silent. Else, the PHY can transition to functional state immediately after the sleep is forced.