| 摘要 |
PROBLEM TO BE SOLVED: To reduce heat generation of an element by heightening a ratio of power regenerated in a power source, out of power based on a counter electromotive voltage generated in a coil 200 for a head pin driving.SOLUTION: A voltage detection circuit 11 changes a level of a signal to be output, according to magnitude of a counter electromotive voltage generated in a coil 200, a control signal generating circuit 12 outputs an on-signal when the counter electromotive voltage becomes a predetermined voltage or more, outputs an off-signal when the counter electromotive voltage becomes less than the predetermined voltage, an FET (Field Effect Transistor) 130 causes the coil 200 to electrically conduct to a smoothing circuit 14 when the on-signal is input, and breaks the conductivity of the coil 200 to the smoothing circuit 14 when the off-signal is input, the smoothing circuit 14 smoothens a current which is based on the counter electromotive voltage and returns the current to a power source, and a transistor 131 discharges charge accumulated in a parasitic capacitance of the FET 130, by using a potential difference generated at both ends of the FET 130 caused by breakage of the conductivity of the coil 200 to the smoothing circuit 14. |
