Patent ID: 9154031
Filing Date: 2015-10-06
Classification: H02M

Abstract:
1. A current mode DC-DC conversion device with fast transient response, comprising: a DC-DC converter, including an inductor and at least one power switch, wherein the power switch is coupled to the inductor, and the DC-DC converter converts an input voltage into an output voltage; a pulse width control unit, coupled to the power switch; a current feedback circuit, for detecting a current passing through the inductor, and for generating a current feedback signal according to the current passing through the inductor; a fast transient feedback circuit, for generating a transient feedback signal according to a first voltage feedback signal, wherein the first voltage feedback signal is responding to the output voltage; a first error amplifier, for amplifying a difference value between the a second voltage feedback signal and a reference signal to generate an error amplification signal, wherein the second voltage feedback signal is responding to the output voltage; an adder, for adding the current feedback signal and the transient feedback signal to generate a modifying current feedback signal; and a comparator, for comparing the error amplification signal with the modifying current feedback signal to generate a comparison signal, and providing the comparison signal to the pulse width control unit, wherein the pulse width control unit controls a duty cycle of the power switch of the DC-DC converter according to the comparison signal; wherein when the DC-DC converter changes from light load to heavy load, the modifying current feedback signal is pulled down by adding the transient feedback signal, and the pulse width control unit increases the duty cycle of the power switch.