Communication device and control method for reducing power consumption

Abstract

A communication device includes a crystal oscillator, an auxiliary circuit, and a control circuit. The crystal oscillator provides a clock for operation of the communication device in a second mode. The auxiliary circuit includes an accumulator and a comparator. The accumulator counts a number according to an MDI (Medium Dependent Interface) signal. The comparator compares the number with a threshold. If the number is greater than or equal to the threshold, the comparator will output a wakeup signal. The control circuit switches from the second mode to a first mode in response to a control signal, and switches from the first mode to the second mode in response to the wakeup signal. In the first mode, the control circuit disables the crystal oscillator and enables the auxiliary circuit. In the second mode, the control circuit enables the crystal oscillator.

Dependencies are inferred from the claim text.