A method for saving electrical power for a physical layer (PHY) device including a plurality of sub-circuits is disclosed. The method includes the steps of outputting a plurality of link pulses, asserting a plurality of disabling signals-between two adjacent link pulses for disabling the sub-circuits, respectively, and deasserting the disabling signals for enabling the sub-circuits, respectively. The disabling signals are asserted separately for disabling the sub-circuits at different time points. A physical layer device for use in a chip for saving electrical power is also disclosed.