a current detection circuit which applies an ac voltage to a vibrator which converts electricity into a mechanical energy to vibrate , and detects a mechanical branch current serving as a current component which contributes to the vibration of the vibrator , includes a series circuit which connects a capacitor to the vibrator in series , voltage dividing circuits , connected to the series circuit in parallel , for dividing and extracting a voltage applied across the series circuit , and a detection circuit for detecting a difference between , of the divided voltages , a terminal voltage other than the voltage applied across the series circuit and a voltage at a connection portion between the vibrator and the capacitor in the series circuit .