Current detection circuit with controllable detection current

Abstract

The invention discloses a current detection circuit with controllable detection current, and particularly relates to the technical field of current detection. The circuit comprises a unit to be detected, a first resistor, a first controllable current source, a second controllable current source, an upper clamping unit and a lower clamping unit, the power voltage end of the circuit is grounded through the first resistor and the to-be-tested unit in sequence. The power supply voltage end is grounded through the first controllable current source and the second resistor in sequence; the upper clamping unit is connected to a connection node of the first controllable current source and the second resistor; the lower clamping unit is connected to a connection node of the first controllable current source and the second resistor. According to the scheme, the voltage difference between the two ends of the second resistor is controlled through the upper clamping unit and the lower clamping unit, so that the voltage difference between the two ends of the second resistor is ensured to be within a certain range, a clamping function for the detection current is generated, a compensation circuit does not need to be additionally added, the complexity of the current detection circuit is reduced, and the detection precision is improved. And the cost of the current detection circuit is also reduced.

Description

technical field [0001] The invention relates to the field of current detection, in particular to a current detection circuit with controllable detection current. Background technique [0002] In the control loop of the prior art, it is usually necessary to detect the current, and input the detected current as a control input into the control loop, so as to realize the normal operation of the control loop. [0003] In order to prevent the detection current obtained by the detection from being too large or too small, after the detection current is input into the control loop, the control loop is out of control and the main power circuit is damaged. Therefore, at this time, it is necessary to The detected detection current is clamped and controlled. In the prior art, when the detection current is clamped and controlled, the current signal is usually converted into a voltage signal, and the closed-loop adjustment is performed through the operational amplifier loop to control the...

AI Technical Summary

Problems solved by technology

[0004] However, in the above solution, the structure of the current detection circuit for detecting the current clamping function is complex, and an additional compensation circuit needs to be added, resulting in a large loss of integrated circuit chip area, and only unilateral current clamping can be performed in the prior art. Bilateral current clamping requires two sets of detection current control systems, further occupying the chip area, and the cost of the current detection circuit is relatively high

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