| 摘要 |
PROBLEM TO BE SOLVED: To provide an antenna driver capable of increasing transmission speed of a transmission signal from an antenna without excessively increasing output intensity of the transmission signal.SOLUTION: A control circuit switches an antenna driver's state between: a full bridge state in which an H bridge circuit applies differential voltage of pulse voltage and inverse pulse voltage obtained by inverting the pulse voltage, to an antenna as antenna drive voltage Vd; and a half bridge state in which the H bridge circuit applies the pulse voltage to the antenna as the antenna drive voltage Vd. The control circuit makes the antenna driver's state be in the full bridge state in a period of starting driving the antenna in a transmission period when the antenna transmits the transmission signal, and be in the half bridge state in a remaining period after the period of starting driving the antenna in the transmission period. |
