基于ADL5303的串列加速器缝隙仪前置放大器的研究

Study of Tandem Accelerator Slits Preamplifier Based on ADL5303

为了满足串列加速器粒子能量高稳定度的要求,需采用缝隙仪来稳定加速高压的方式,利用缝隙仪高、低能端束流强度的差异反馈稳定头部高压。由于束流变化动态范围较大,在前置放大器中采用对数放大来满足束流强大动态范围的要求。根据串列加速器高压稳定系统的实际需要,设计了采用ADL5303的对数前置放大器电路,并对该电路做了仿真和实验测试,得到了理论和实际对数放大曲线。结果表明,对数放大器范围可以从100 pA到1 mA,可以实现大范围束流变化下对高压稳定系统的调节。

In order to meet the requirements of high stability of particle energy in a tandem accelerator,it is necessary to rely on the slits to stabilize the acceleration high voltage,and control the stability of the terminal high voltage by using the differential feedback of the beam intensity signal at the high and low energy ends of the slits.Due to the large dynamic range of beam changes,logarithmic amplification is used in the preamplifier to meet the wide dynamic range of beam current.According to the actual demands of the high-voltage stabilization system of the tandem accelerator,a logarithmic preamplifier circuit using ADL5303 is designed,the circuit is simulated and tested,and the theoretical and practical logarithmic amplification curves are obtained.The results show that the logarithmic amplifier can achieve a 100 pA response from 100 pA to 1 mA,and realize the regulation of high-voltage stable systems under a wide range of beam changes.