为获得宽频带的无源积分器, 建立了考虑杂散参数的等效电路并进行了电路仿真。结果表明无源积分器的频响上限由杂散参数决定。对于相同结构的积分器, 增大RC积分常数, 会使杂散参数的影响加剧, 导致积分器的高频响应变差。使用同轴结构可以减小电容的杂散电感, 提高积分器的带宽。对制作的RC常数为10 μs的同轴式积分器进行了频响实验。实验结果表明：在偏差小于5％的范围内, 同轴式积分器带宽为50 kHz～80 MHz。在D-dot电压探头线下标定实验和初级试验平台(PTS)单路样机激光触发开关输出电压测量中, 使用该同轴积分器获取的测量波形没有波形畸变和高频干扰。

The equivalent circuit of passive integrator has been established and simulated considering its stray parameters. The higher frequency restriction of the integrator is found to be determined by the stray inductance from integral capacitor and the stray capacitance from integral resistor, whose influence grows as the RC time constant increases, for integrators of the same structure. Coaxial structure can reduce the stray inductance from integral capacitor and thus enlarge the bandwidth of the integrator. A coaxial passive integrator with the RC time constant of 10 μs has been designed and fabricated. Frequency response tests show that, its operation band ranges from 50 kHz to 80 MHz when the error is less than 5%. The output waveform of the integrator connected with a D-dot probe is not distorted for square input with rise edge of 8 ns. And no high frequency interference is observed when the integrator is used to measure the switch output voltage for the prototype module of the Z-pinch primary test stand(PTS).