SAWTOOTH WAVE GENERATING CIRCUIT CAPABLE OF OUTPUTTING A SAWTOOTH WAVE SIGNAL AFTER PERFORMING CALIBRATION, AND A SWITCH MODE POWER SUPPLY INCLUDING THE SAME

摘要

PURPOSE: A sawtooth wave generating circuit and a switch mode power supply including the same are provided to generate a stable DC output voltage through a stable switch control signal by outputting a sawtooth wave signal after performing calibration.;CONSTITUTION: A capacitor(CS) is coupled between a first node and a ground. A calibration circuit(140) feeds back a sawtooth wave signal from the first node, and generates a plurality of voltage signals based on the sawtooth wave signal. The calibration circuit selects one of the voltage signals, and generates a calibration output signal. A charge circuit(110) charges the capacitor in response to the calibration output signal. A discharge circuit(120) discharges the capacitor in response to a short pulse signal.;COPYRIGHT KIPO 2010