Single-inductor multi-output DC-DC buck converter

Abstract

The invention discloses a single-inductor multi-output DC-DC buck converter, relates to the technical field of DC-DC converters, and solves the technical problem that the performance requirements of transmission efficiency, cross modulation and output ripple waves are difficult to consider in an existing SIMO control method. The single-inductor multi-output DC-DC buck converter comprises a powerconversion unit and an i-path charge controller, and further comprises a phase-locked loop, a logic unit, a driving unit and an input trunk duty ratio generation unit, wherein the charge controller isconnected with the driving unit through the logic unit, the logic unit is further connected with the phase-locked loop, the phase-locked loop is connected with the driving unit through the input trunk duty ratio generation unit, and the driving unit is connected with the power conversion unit. Charge control is carried out for each output branch, and the phase-locked loop is used as period control, so that the cross modulation effect of each branch is effectively inhibited, the last branch is not required to have enough load, and the load range is widened; and meanwhile, other performance requirements are well considered.

Description

technical field [0001] The invention relates to the technical field of DC-DC converters, more specifically, it relates to a single-inductance multi-output DC-DC step-down converter. Background technique [0002] Single Inductor Multiple Outputs Buck DC-DC (Single Inductor Multiple Outputs Buck DC-DC, SIMO Buck DC-DC) technology, hereinafter referred to as SIMO, is a switching converter. Such as figure 1 As shown, SIMO makes one DC input generate DC outputs of multiple branches by using only one inductor and complex capacitors, which is mainly used in the scene of DC voltage source conversion. SIMO takes into account the high-efficiency characteristics of switching converters, and improves the layout utilization rate, adapting to the development trend of integrated circuits. However, compared with the development level of single-inductor single-output DC conversion technology, SIMO still has problems such as low transmission efficiency, serious cross-modulation phenomenon, ...

AI Technical Summary

Problems solved by technology

However, at present, this method uses a comparator for control. The output voltage controlled by the comparator has a large ripple and low output voltage accuracy. On the other hand, the control of the comparator is nonlinear, which is not suitable for the current linear design method of SIMO.

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