DC-DC controller and multi-ramp signal operating method thereof

摘要

A DC-DC controller and a multi-ramp signal operating method thereof are provided. The DC-DC controller includes a ramp generating unit, a comparator, a logic circuit and a switch unit. The ramp generating unit generates a first interior-ramp signal and a second interior-ramp signal alternately. The logic circuit generates the first and second control signals according to a comparison signal of the comparator. The switch unit is configured to switch one of the first interior-ramp signal and the second interior-ramp signal alternately to a second terminal of the comparator according to the first and second control signals. When the second interior-ramp signal is switched to the comparator, the first interior-ramp signal is charged to a first voltage level by the ramp generating unit. In another switch procedure, the second interior-ramp signal is charged to a second voltage level by the ramp generating unit.

主权项

1. A direct current (DC)-DC controller, comprising:
a ramp generating unit, generating a first interior-ramp signal and a second interior-ramp signal; a comparator, having a first input terminal receiving an error signal, and an output terminal outputting a comparison signal, wherein the error signal relates to an output voltage; a logic circuit, generating a first control signal and a second control signal according to the comparison signal; and a switch unit, coupled to the ramp generating unit and the logic circuit, and alternately switching one of the first interior-ramp signal and the second interior-ramp signal to a second input terminal of the comparator according to the first control signal and the second control signal, wherein when the second interior-ramp signal is switched to the comparator, the ramp generating unit charges the first interior-ramp signal to a first voltage level, and when the first interior-ramp signal is switched to the comparator, the ramp generating unit charges the second interior-ramp signal to a second voltage level.