Power supply apparatus and image forming apparatus

摘要

The power supply apparatus includes a transformer having a primary side and a secondary side insulated from each other, a switch element for switching current flowing in the primary side of the transformer, a control part configured to control an operation of the switch element, and two feedback parts configured to detect an output voltage from the transformer so as to output, to the control part, a detection signal in accordance with the output voltage for feedback to the primary side of the transformer.

主权项

1. A power supply apparatus, comprising:
a transformer having a primary side and a secondary side insulated from the primary side; a switch element for switching current flowing in the primary side of the transformer; a control part configured to control an operation of the switch element so as to control an output voltage of the secondary side of the transformer; and a first detection part configured to detect the output voltage from the secondary side of the transformer and to supply the control part a first signal in accordance with the detected output voltage, a second detection part configured to compare an output value according to the output voltage on the secondary side of the transformer and a threshold value and supply a second signal based on a result of the comparison to the control part, the second detection part configured to switch an output condition of the secondary signal according to an external signal; wherein in a case where a target value of the output voltage on the secondary side of the transformer is a first target voltage, the control part controls the switching of the switch element according to the first signal detected by the first detection part, and in the case where a target value of the output voltage on the secondary side of the transformer is lower than a second target voltage lower than the first target voltage, the control part controls the switching of the switch element according to the second signal detected by the second detection part.