DC-DC converter with line loss compensation function

Abstract

The invention relates to a DC-DC converter with a line loss compensation function. The DC-DC converter comprises a control circuit and a filtering circuit; after input voltage passes through the control circuit and the filtering circuit, output voltage of a chip can be generated. Compared with the prior art, the control circuit further comprises a line loss compensation module; after passing through a feedback resistor, the output voltage of the chip is fed back to the reverse input end of an error amplifier in the control circuit; and the line loss compensation module changes reference voltage inputted into the forward input end of the error amplifier according to the voltage of the output end of the error amplifier, so as to compensate the output voltage of a load. With the DC-DC converter with the line loss compensation function provided by the above technical scheme of the invention adopted, the output voltage VEA of the error amplifier is utilized to control compensation amplitude, and therefore, an excellent linear relation between compensation amplitude and output current can be realized; a line loss compensation function is fully integrated in the chip, and therefore, additional auxiliary devices are not required to be adopted at the exterior of the DC-DC converter, and complicated debugging calculation is not required.

Description

technical field [0001] The invention relates to the field of circuits, in particular to a power supply circuit, in particular to a DC-DC converter with line loss compensation. Background technique [0002] At present, the charging current of portable devices such as mobile phones and PADs is getting larger and larger, and the voltage loss on the output connection line is becoming more and more significant during the high-current charging process, especially when the output connection line is long. more serious. It will cause the final charging voltage to the charging device to drop significantly. Because the charging voltage drops, the charging management module inside the charging device will automatically reduce the charging current to adapt, so the charging power will drop significantly, the charging time will become longer, and even normal charging will not be possible. question. [0003] In order to deal with this situation, there are generally two ways to deal with i...

AI Technical Summary

Problems solved by technology

[0009] This method can accurately control the required compensation range, but it needs an external op amp to realize it, which increases the cost and design difficulty, and once the design is determined, the compensation range cannot be changed, which lacks flexibility.

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