针对电气设备局部放电信号宽频带、传感器输出信号幅值差异显著等问题，设计了一种基于0.18 μm CMOS工艺的宽动态范围可重构对数放大器。为兼顾宽带响应与宽动态范围检测能力，采用连续检波对数放大架构，通过多级限幅放大与全波检波电路相结合，实现输入信号的对数压缩。为提高偏置稳定性并降低工艺及温度变化影响，引入恒跨导自偏置电路，提高各级限幅放大单元偏置电流和静态工作点的一致性。针对不同检测场景对对数斜率差异化需求，提出一种基于片上数字开关阵列的对数响应斜率重构方法。在保持主体电路结构不变的条件下，通过数字开关阵列选择不同检波电流支路的输出，实现多档对数响应斜率的灵活配置。仿真结果表明，在2 V电源电压下，实现40 MHz的-3 dB带宽，有效输入动态范围达到72 dB，对数一致性误差在±1.9 dB以内，支持实现八档斜率配置。该放大器兼顾宽频带、宽动态范围及可重构特性，可满足局部放电在线监测系统对多传感器适配、宽动态范围检测及多档输出配置的应用需求。

A wide-dynamic-range reconfigurable logarithmic amplifier based on 0.18 μm CMOS process is designed to address the problems of wide bandwidth of partial discharge signals of electrical equipment and significant amplitude difference in sensor output signals. To balance broadband response and wide dynamic range detection capability, a successive detection logarithmic amplification architecture is adopted, which combines multi-stage limiting amplification with full-wave detection circuits to realize logarithmic compression of input signals. To improve bias stability and reduce the influences of process and temperature variations, a constant-transconductance self-bias circuit is introduced to enhance the consistency of bias current and static operating point of each limiting amplification unit. Aiming at the differentiated requirements of logarithmic slopes in different detection scenarios, a logarithmic response slope reconfiguration method based on an on-chip digital switch array is proposed. With the main circuit structure unchanged, flexible configuration of multiple logarithmic response slopes is realized by selecting outputs of different detection current branches through the digital switch array. Simulation results show that the designed amplifier achieves a −3 dB bandwidth of 40 MHz and an effective input dynamic range of 72 dB under a 2 V supply voltage, with the logarithmic conformity error within ±1.9 dB and eight adjustable slope gears supported. Integrating broadband performance, wide dynamic range and reconfigurable characteristics, the proposed amplifier can meet the application requirements of partial discharge online monitoring systems for multi-sensor adaptation, wide-dynamic-range detection and multi-gear output configuration.