| 摘要 |
<p>PROBLEM TO BE SOLVED: To shorten a control delay time due to the changeover of a drive antenna or a current setting value by simultaneously driving multiple antennas by different current values while suppressing the increase of a circuit configuration.SOLUTION: At least one antenna 2A between the antennas to be simultaneously driven is defined as a carrier amplitude setting antenna. A detection selection switch 9A is turned on to thereby digitally control a voltage setting value (a carrier amplitude setting value) to allow a current detected by an antenna current detection circuit 4 to be within a current target range. At least an antenna 2B between the antennas to be simultaneously driven is defined as a current limit setting antenna. A detection selection switch 9B is turned on to thereby digitally controlling an on-resistance setting value B (a current limit setting value B) to allow a current detected by the antenna current detection circuit 4 to be within a current target range.</p> |
