Pulse width modulation apparatus and apparatus for driving light source having the same

Abstract

Provided are a pulse width modulation (PWM) apparatus and a light source-driving apparatus including the PWM apparatus. The PWM apparatus includes a voltage division part, a capacitor part, a first operational amplifier, a first noise reduction part, and a second operational amplifier. The voltage division part divides and outputs an input voltage. The capacitor part charged by an input current or discharged for provides a charge voltage. The first operational amplifier operates according to a result of comparing a divided voltage output from the voltage division part with the charge voltage output from the capacitor part. The first noise reduction part removes a high frequency noise of the divided voltage. The second operational amplifier converts a signal generated from the capacitor part into a pulse width modulation signal by a dimming control signal.

Dependencies are inferred from the claim text.