| 摘要 |
PROBLEM TO BE SOLVED: To prevent impedance variation from becoming small owing to the on/off switching of an FET and to eliminate loss due to a reactive current. SOLUTION: This medium is equipped with an antenna coil L, a resonant capacitor C which is connected across the antenna coil L, a diode D which has its anode connected to one terminal of the antenna coil L, and an N-channel FET (switch element SW) which has its drain connected to the cathode of the diode D and its source connected to the other terminal of the antenna coil L, and the reactive current is not caused to flow through a parasitic diode PD generated between the source and drain of the H-channel FET. |
