Wide-load range, high-precision and low-power consumption current detection circuit

Abstract

The invention discloses a wide-load range, high-precision and low-power consumption current detection circuit. The current detection circuit comprises a cascade current mirror, a power stage output circuit, a detection circuit and a switching circuit and also comprises five metal-oxide semiconductor (MOS) transistors M6 to M10, wherein the cascade current mirror consists of M2 to M5; the power stage output circuit consists of MN1, L and C; the detection circuit consists of MP1 and MP2; and the switching circuit consists of MS1 and MS2. By using the current detection circuit, a nonlinear errorcaused by a bias current is eliminated on the basis of properly increasing circuit complexity and ensuing low power consumption, so that the detection precision is improved on the premise of low power consumption of an improved current detection circuit; therefore, the aim of improving the performance of an overall direct current-direct current (DC-DC) system is fulfilled.

Description

Technical field [0001] The invention relates to a wide-load range high-accuracy low-power consumption current detection circuit applied to a step-down DC-DC, and belongs to the technical field of power-level analog integrated circuits. Background technique [0002] The power management chip is an indispensable part of modern electronic products, and it becomes particularly prominent as people’s requirements for the standby time of electronic products increase. Therefore, the design of high-efficiency and high-performance power management chips is full of challenges, and it is aimed at power management design The improvement of technology is of great significance. [0003] DC-DC is the most commonly used power management chip. Most of the existing step-down DC-DC adopts the peak current mode of voltage and current dual-loop control. Therefore, the current detection circuit as the core of the current loop is particularly important. Its detection accuracy is very important. The stabi...

AI Technical Summary

Problems solved by technology

[0012] In the traditional current detection circuit formula (1) and formula (2), the bias current I must be subtracted due to the induced current 1 However, the nonlinear error is introduced, so that the final detection accuracy is affected, and this nonlinear error will become more obvious under the requirement of low power consumption; in addition, the traditional current detection circuit cannot guarantee normal operation in a wide load range under the premise of low power consumption. Work

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