Pulse width modulation circuit and illumination apparatus

摘要

An illumination apparatus includes a power supply, a pulse width modulation (PWM) circuit, a switching unit, and an illuminating unit. The power supply supplies a supply voltage to the PWM circuit and the illuminating unit. The PWM circuit outputs a first level voltage by being fully charged by the voltage of the power supply and outputs a second level voltage by being fully discharged. The switching unit is turned off according to the first level voltage and controls the illuminating unit to stop emitting light. The switching unit is turned on according to the second level voltage and controls the illuminating unit to emit light.

主权项

1. An illumination apparatus being powered by a supply voltage of a power supply, the illumination apparatus comprising:
a pulse width modulation (PWM) circuit for receiving the supply voltage connected to the power supply; a switching unit; and an illuminating unit adapted to emit light; wherein the PWM circuit outputs a first level voltage when being fully charged by the supply voltage, the switching unit is turned off according to the first level voltage and controls the illuminating unit to emit light, the PWM circuit outputs a second level voltage when fully discharged, the switching unit is turned on according to the second level voltage and controls the illuminating unit to stop emitting light.