Voltage generating device and image forming apparatus including the same

摘要

A power supply apparatus outputs a developing voltage in which a pulse wave shape at a time of positive amplitude is different from a pulse wave shape at a time of negative amplitude. Voltages are supplied from two switching regulators respectively to a bridge circuit for driving a transformer. Here, an absolute value of a difference between a drive frequency of a first switching regulator and a drive frequency of a second switching regulator is configured to be not less than an invisible frequency at which a banding cannot be recognized by humans.

主权项

1. An image forming apparatus, comprising:
a developing unit configured to carry out developing by causing a developer to adhere to an electrostatic latent image formed on an image carrier; and a voltage generating circuit configured to supply to the developing unit a development bias voltage in which a voltage of a positive pulse is different from a voltage of a negative pulse; wherein the voltage generating circuit comprises
a voltage conversion unit configured to convert a voltage inputted from a primary side to a voltage of a different magnitude and outputs to a secondary side,a bridge circuit connected to the primary side,a first switching regulator configured to generate a first voltage to be applied to the bridge circuit, anda second switching regulator configured to generate a second voltage to be applied to the bridge circuit, and wherein a drive frequency of the first switching regulator and a drive frequency of the second switching regulator are configured so that an absolute value of a difference between the drive frequency of the first switching regulator and the drive frequency of the second switching regulator is not less than a predetermined frequency.