A transceiver circuit having 10 mb and 100 mb transmit and receive circuitries using the power saving methods of the present invention is disclosed. The power consumption of the transceiver circuit can be significantly reduced by providing each defined subcircuit with its own power supply and means of activation and deactivation. However, the method for activating and deactivating digital subcircuits and analog subcircuits are different and therefore different types of control signals and methods are provided. Furthermore, there are two general types of power-saving situations. The first type is near total circuit power-down and the second type is partial circuit power-down. The present invention in yet another embodiment discloses a method for minimizing energy usage during idle period.