中圖分類號：TN402 文獻標志碼：A DOI: 10.16157//j.issn.0258-7998.246100 中文引用格式： 李新，俞晨,，楊森林. 一種應(yīng)用于電流檢測的低失調(diào)運算放大器設(shè)計[J]. 電子技術(shù)應(yīng)用,，2025，51(5)：5-9. 英文引用格式： Li Xin,，Yu Chen,，Yang Senlin. Design of a low offset operational amplifier for current detection[J]. Application of Electronic Technique，2025,，51(5)：5-9.
Design of a low offset operational amplifier for current detection
Li Xin1,，Yu Chen1，Yang Senlin2
1.School of Information Science and Engineering,， Shenyang University of Technology,； 2.Shenzhixin Microelectronics （Shanghai） Co.， Ltd.
Abstract： Aiming at the requirement of current detection for operational amplifier performance, a new low offset operational amplifier circuit is proposed. The closed-loop current sampling circuit is composed of low-loss op-amp, PMOS tube and resistor. The whole op-discharge route is composed of main op-amp and auxiliary op-amp. The high frequency path composed of main op-amp controls the circuit bandwidth, the auxiliary amplifier low-frequency path uses chopper technology and self-zeroing technology to reduce the circuit offset. The circuit was simulated based on the 180BCD process. The simulation results show that the temperature is 27 ℃, the input offset voltage is stable at 9 μV, the operation amplifier gain is 95.50 dB, the gain bandwidth product is 28.2 MHz, the phase margin is more than 76.6°, the CMRR value is 148 dB, and the PSRR value is more than 116 dB. The circuit can be used for high measurement current detection.
Key words : operational amplifier,；current detection,；chopper technology；self-zero technology
