LIGHT EMITTING ELEMENT DRIVING CIRCUIT

摘要

A light emitting element driving circuit comprising: a rectifying circuit; a voltage-dividing circuit; a transistor increasing or reducing a driving current of a light emitting element according to turning on or off a rectified voltage; a control circuit bringing the transistor to an on or off state at predetermined intervals and bringing the transistor to the other state when a voltage according to a current flowing through the transistor increases and becomes the reference voltage being divided voltage obtained by dividing the rectified voltage; and a voltage-dividing ratio adjustment circuit to set a voltage-dividing ratio of the voltage dividing circuit as a first voltage-dividing ratio to reduce the reference voltage when an amplitude of the rectified voltage is larger than predetermined amplitude and to set the voltage-dividing ratio as a second voltage-dividing ratio to increase the reference voltage when an amplitude of the rectified voltage is smaller than predetermined amplitude.