Patent ID: 8258922

Claim:
An electronic device comprising: a receiving module for receiving external wireless signals; a checking module configured for checking if a current wireless signal comprises checking codes of a control signal which is configured for controlling the electronic device and, if yes, generating an activation signal; and a controller configured for switching the electronic device into a power-saving mode if no external wireless signal is received after a predetermined time period and switching the electronic device into a normal mode if the activation signal is received; wherein the checking module comprises a first terminal, a second terminal, and a third terminal, the controller comprising a clocker for generating timing signals; the first terminal being connected to the receiving module for receiving the external wireless signals; the second terminal being connected to the clocker for receiving the timing signals; the checking module being configured for sequentially sampling codes of the current wireless signal upon receiving each of the timing signals; the third terminal being connected to the controller and configured for outputting the activation signal to the controller, wherein the checking codes of the control signal comprises first n codes; the checking module comprises n corresponding circuits and an adder, wherein n is an integer, the i-th circuit comprises i D-type registers, i is a positive integer, and i≦n; each D-type register comprising an input terminal, a clocking terminal, and an output terminal; wherein the registers of the same circuit are serially connected between the first terminal and the adder via the input terminals and the output terminals thereof, the clocking terminals are connected to the second terminal, and the adder is connected to the third terminal.