SNLA411 October 2022 DP83TC812R-Q1 , DP83TC812S-Q1 , DP83TC813R-Q1 , DP83TC813S-Q1
Many power supply networks share the PMIC between different PHYs available on the same PCB board to reduce the number of components and the board area.
In this case, the INH of the different PHYs can be connected together and this signal functions are Wired-OR (due to the open drain configuration of INH). The power supplies are cut-off only after all the PHYs are in sleep mode. Hence, there will be high current consumption from the supplies even though one or some of the PHYs are in sleep. The functionality of the PHYs in sleep will not be affected during this case. To achieve the lowest power consumption in the above case, PMIC must be separated for both the PHYs.
Figure 5-2 shows one of the examples where two PHYs share the same PMIC.