N-phase integrated buck converter

Abstract

The invention provides an n-phase integrated step-down converter (10). The converter (10) includes a controller (20) and a plurality of circuits (12), each of which is operatively connected to the controller (20). The controller controls a plurality of circuits (12) to respectively output a plurality of current signals and generate an output voltage signal, each of the plurality of current signals having an associated phase. By applying the n-phase concept of the present invention, the amount of current to be delivered per phase (ie each of the multiple circuits) is reduced. This directly reduces conduction losses per phase. Since the current per phase is lower, smaller MOSFETs can be used in each of the multiple circuits. The smaller MOSFETs are easier to switch. Therefore, the switching loss of each phase is reduced. Reducing these losses will allow the present invention to achieve high efficiency. Integration makes all components physically closer and can be switched more quickly. Higher switching frequencies allow for smaller and fewer passive components. Integration also minimizes the overall cost of the converter (10).

Description

technical field [0001] The present invention relates generally to semiconductor integrated circuit (IC) devices, and more particularly to buck converters. Background technique [0002] A buck converter is used to convert a higher voltage to a lower voltage suitable for use, for example, by a microprocessor. Buck converters typically operate using a clock whereby the inductor is charged during the first part of the clock cycle ("charge phase") and operates as a power source during the second part of the clock cycle ("discharge phase"). More recently, buck converters have evolved into multiphase buck regulators. Conventional multiphase buck converters allow multiple low currents to be sent through multiple phases, respectively. The sum of the inductor currents is provided as an output. Such conventional multiphase converters suffer from serious drawbacks, since the different phases cannot be superimposed on each other. Additionally, the controller cannot differentiate the ...

AI Technical Summary

Problems solved by technology

Such conventional multiphase converters suffer from a serious drawback, since the different phases cannot be superimposed on each other

In addition, the controller cannot differentiate the resulting inductor current, which leads to unstable or ineffective control

Non-superimposed phases result in slower response times for high current outputs

Therefore, conventional multiphase converters usually cannot include too many phase

[0003] Traditional multiphase converters are also subject to constraints related to discrete implementation processes, including response time, efficiency, and cost

The response time in discrete circuits is usually longer due to the greater distance between discrete circuit elements, which also results in a larger time constant

Discrete circuits are inefficient due to higher switching losses

Discrete circuits are also more expensive than integrated circuits

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