A Wide Input Common Mode Voltage Range Current Sense Amplifier Circuit

Abstract

The invention discloses a current detection amplifier circuit with a wide input common-mode voltage range, which belongs to the technical field of current detection amplifier circuits, and realizes an ultra-wide-range common-mode voltage input by using an operational amplifier with a limited input common-mode range in a low-voltage domain during current detection , the high-voltage voltage drop is dropped on the resistor, and all computing circuits are realized by low-voltage devices, without the need to generate additional high-voltage voltage sources and use high-voltage devices, and can realize the required functions in an ultra-small area.

Description

technical field [0001] The invention relates to a current detection amplifier circuit, in particular to a current detection amplifier circuit with a wide input common-mode voltage range, belonging to the technical field of current detection amplifier circuits. Background technique [0002] In the power system, it is necessary to detect the load current in real time. In the prior art, when the detection point is on the power line or the ground line, the input common-mode voltage is the power supply voltage or the ground line voltage, and the comparator is easy to implement. If it is necessary to directly detect the voltage on the load When the current is high, the common-mode voltage changes in a wide range when the load is turned on and off. Due to the inductive load and wiring inductance, it may even be higher than the power supply voltage or lower than the ground level. The input common-mode range requirements of the corresponding operational amplifier From negative voltag...

AI Technical Summary

Problems solved by technology

[0002] In the power system, it is necessary to detect the load current in real time. In the prior art, when the detection point is on the power line or the ground line, the input common-mode voltage is the power supply voltage or the ground line voltage, and the comparator is easy to implement. If it is necessary to directly detect the voltage on the load When the current is high, the common-mode voltage changes in a wide range when the load is turned on and off. Due to the inductive load and wiring inductance, it may even be higher than the power supply voltage or lower than the ground level. The input common-mode range requirements of the corresponding operational amplifier From negative voltage to higher than the power supply voltage, additional high voltage devices are required to occupy the chip area and increase the cost. Therefore, a current sense amplifier circuit with a wide input common mode voltage range is designed to optimize the above problems

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