| 摘要 |
PROBLEM TO BE SOLVED: To supply a stable driving voltage to a control IC while preventing an excessive voltage from being applied to the control IC even at normal time when an over voltage does not occur.SOLUTION: In a power supply control device, a first auxiliary winding 25c and a second auxiliary winding 25d having numbers of turns different from each other are provided in a transformer 25, and a control signal CS on the basis of a power supply voltage required by a printer is input. The power supply control device is provided with a driving voltage output circuit 34 that rectifies a voltage in response to the control signal CS out of AC voltages induced by the first auxiliary winding 25c and the second auxiliary winding 25d and can output a DC voltage smoothed as a driving voltage of a control IC 38. On account of this, the power supply control device outputs the voltage from the second auxiliary winding 25d having the smaller number of turns when a voltage Vout is relatively high and can protect the control IC 38 from an over voltage. The power supply control device outputs the voltage from the first auxiliary winding 25c having the larger number of turns when the voltage Vout is relatively low and can stabilize the driving voltage. |
