Design of lossless current-sensing circuit

Abstract

A novel current detection circuit based on RC parallel inductor lossless current-sense technology is proposed to overcome the low efficiency of high current conversion in traditional series resistance detection.The circuit can accurately detect the instantaneous-current and average-current of inductive current at the same time and improve the detection efficiency. The main circuit consists of three parts: high precision and low speed current detection with correction, fast current detection and feedback calibration circuit. The first part detects the average value of the current, and the fast current detection circuit is calibrated by feedback calibration circuit to accurately detect the instantaneous value of the current. The problem of current reflux is solved by negative current generating circuit.The circuit is designed by TSMC 180 nm 1P3M GEN2 process and simulated by Cadence software.The results show that this method can obtain the the average and instantaneous value of the inductive current while ensuring the detection of inductive current.

Keywords

• high current
• lossless current-sense technology
• inductive current
• instantaneous-current
• average-current