| 摘要 |
PURPOSE:To suppress the rise of the output current in the low frequency range and in the vicinity of resonance point by connecting two series resistors and a diode in series between the output terminal of a drive constant-current source and a sensitive terminal and connecting the neutral point of the resistance through a diode to the source. CONSTITUTION:A pulse motor 21 driven by the output of a constant-current source 1, is rotated at an angle corresponding to the opening or closing of a drive coil switching circuit 11, and is driven stepwisely as prescribed. Further, a capacitor (C) 31 is connected in parallel with the circuit 11, resistors (R) 32, 33 and a diode (D) 34 are connected in series with each other, and the neutral point of the R32, 33 is connected to the DC constant voltage circuit 36 of the voltage lower than the current source 1 in a compensating circuit 37. Which is inserted between the terminal 1a of the source 1 and the sensitive terminal 4b, and one end of the R16 is connected to the terminal 4b through the R38. With the circuit 37 the increases in the output current in the low frequency range and the output current in the vicinity of the resonance point in the middle frequency range are suppressed, thereby improving the frequency characteristics of the output current. |
