| 摘要 |
<P>PROBLEM TO BE SOLVED: To prevent malfunctioning such as an incorrect operation or no response caused by using a clock generated on the basis of a demodulation signal, of a semiconductor device capable of performing data communications by wireless. <P>SOLUTION: The semiconductor device has an antenna circuit for receiving a wireless signal, a power supply circuit generating power by the wireless signal received by the antenna circuit, and a clock generation circuit to which power is supplied. The clock generation circuit includes a ring oscillator which self-oscillates, and a frequency divider which adjusts the output signal of the ring oscillator so as to have a frequency in an appropriate range. By driving a digital circuit portion by a clock having high frequency accuracy, a malfunction such as an incorrect operation or no response is prevented. <P>COPYRIGHT: (C)2008,JPO&INPIT |
