Patent ID: 8179088

Claim:
A noncontact transmission device which transmits at least one of electric power and a data signal to a device to which at least one of the electric power and the data signal is to be transmitted by means of electromagnetic coupling via a coil, the noncontact transmission device comprising: a driver which drives the coil; a system clock oscillator which outputs a system clock; a monitoring clock oscillator which outputs a monitoring clock having a frequency lower than a frequency of the system clock; and a control circuit which operates by using the system clock and the monitoring clock and outputs a control signal for the driver and a control signal for the system clock oscillator, wherein during a standby period prior to start of transmission of at least one of the electric power and the data signal, the control circuit outputs the control signal for the system clock oscillator based on the monitoring clock to cause the system clock oscillator to intermittently output the system clock in synchronization with the control signal for the system clock oscillator, and, during a period in which the system clock is being output, drives the coil by the control signal for the driver to detect whether or not the device to which at least one of an electric power and a data signal is to be transmitted is placed.