Patent ID: 9684320
Date: 2017-06-20
CPC Classifications: G05F,H02M

Claim:
1. A DC/DC converter comprising: n converters, each converter comprising a first switch device, connected in parallel to each other and configured to adjust a level of an input voltage according to a duty ratio of a first pulse signal applied to the first switch device to output an output voltage, wherein the n is an integer of 2 or more; and a control unit configured to compare an average of n sensing currents with the n sensing currents sensed from the n converters, respectively, to adjust the duty ratio of the first pulse signal, wherein the control unit comprises: a current sensing unit configured to detect and amplify the n sensing currents and output n first output voltages; an average unit configured to average the n first output voltages and output an average voltage; and a current balance unit configured to compare the average voltage with the n first output voltages and output n second output voltages, wherein the duty ratio of the first pulse signal is adjusted by one of the n second output voltages, wherein the current sensing unit includes first to n-th current sensing sub-units each of which detects one of the n sensing currents and outputs one of the n first output voltages, and wherein each of the first to n-th current sensing sub-units comprises: a first amplifier configured to non-inverting amplify the sensing voltage; a second amplifier configured to amplify a differential signal between an output of the first amplifier and the sensing signal; a first resistor connected between a non-inverting terminal of the first amplifier and a node N, wherein the first resistor is one of sensing resistors; a second resistor connected between an inverting terminal of the first amplifier and the node N; a third resistor connected between an output terminal of the first amplifier and the inverting terminal of the first amplifier; a fourth resistor connected between the output terminal of the first amplifier and an inverting terminal of the second amplifier; a fifth resistor connected between the output terminal of the first amplifier and a non-inverting terminal of the second amplifier; a sixth resistor connected between the non-inverting terminal of the second amplifier and a ground; and a seventh resistor connected between the inverting terminal of the second amplifier and an output terminal of the second amplifier.