| 摘要 |
PROBLEM TO BE SOLVED: To obtain a motor controlling circuit for a mirror device having a small number of elements and a simple structure. SOLUTION: In the motor controlling circuit 10 for the mirror device, until electric charge of not less than predetermined amount is accumulated on a capacitor 36, current A1 of a certain degree passes, and a resistance 30 indicates large voltage drop. Therefore, voltage not less than a predetermined value is applied, and an MOSFET24 is turned on, so that driving current A2 starts to pass, and a motor 20 is driven. The electric charge of not less than the predetermined amount is accumulated on the capacitor 36. When the voltage of the capacitor 36 is increased, the current A1 passing through a Zener diode 34 is decreased, and the voltage becomes not more than Zener voltage. Then, the impedance of the Zener diode 34 is extremely increased, and the current A1is extremely decreased, and the voltage drop of the resistance 30 is suddenly made to be small. So that, terminal voltage is rapidly lowered, and the MOSFET24 is turned off. Therefore, supply of the driving current A2 to the motor 20 is intercepted. COPYRIGHT: (C)2006,JPO&NCIPI
|
