| 摘要 |
PURPOSE:To reduce the number of places to be adjusted and reduce the dimension of the device by using the pulse duration modulation signals in common for a plurality of duty valves. CONSTITUTION:A pulse-duration modulator 1 is constituted of a carrier generating circuit 4 having the carrier frequency for preventing the intermission of the holding currents of the duty valves 31-33, and a level comparator 5 having a pulse-duration modulation signal PWM. The driving circuits 21-23 are driven by the duty signals D1-D3 and the pulse-duration modulation signal PWM. The transistors 91-93 for controlling the holding current are driven by the AND condition between the duty signals D1-D3 and the pulse modulation signal PWM, and the transistors 111-113 for quick break are ON/OFF-controlled by the duty control is signals D1-D3.
|
