Schussheim Daniel T, Gibble Kurt
Department of Physics, The Pennsylvania State University, University Park, Pennsylvania 16802, USA.
Rev Sci Instrum. 2023 Aug 1;94(8). doi: 10.1063/5.0157330.
We describe a many-channel experiment control system based on a field-programmable gate array (FPGA). The system has 16 bit resolution on 10 analog 100 megasamples-per-second (MS/s) input channels, 14 analog 100 MS/s output channels, 16 slow analog input and output channels, dozens of digital inputs and outputs, and a touchscreen display for experiment control and monitoring. The system can support ten servo loops with 155 ns latency and MHz bandwidths, in addition to as many as 30 lower bandwidth servos. We demonstrate infinite-impulse-response (IIR) proportional-integral-differential filters with 30 ns latency by using only bit-shifts and additions. These IIR filters allow timing margin at 100 MS/s and use fewer FPGA resources than straightforward multiplier-based filters, facilitating many servos on a single FPGA. We present several specific applications: Hänsch-Couillaud laser locks with automatic lock acquisition and a slow dither correction of lock offsets, variable duty cycle temperature servos, and the generation of multiple synchronized arbitrary waveforms.
我们描述了一种基于现场可编程门阵列（FPGA）的多通道实验控制系统。该系统在10个模拟100兆样本每秒（MS/s）输入通道上具有16位分辨率，14个模拟100 MS/s输出通道，16个慢速模拟输入和输出通道，数十个数字输入和输出，以及用于实验控制和监测的触摸屏显示器。该系统除了支持多达30个较低带宽的伺服系统外，还能支持十个延迟为155纳秒且带宽为兆赫兹的伺服回路。我们通过仅使用移位和加法演示了延迟为30纳秒的无限脉冲响应（IIR）比例积分微分滤波器。这些IIR滤波器在100 MS/s时允许有定时裕量，并且比直接基于乘法器的滤波器使用更少的FPGA资源，便于在单个FPGA上实现多个伺服系统。我们展示了几个具体应用：具有自动锁相获取和锁相偏移慢抖动校正的 Hänsch-Couillaud 激光锁相、可变占空比温度伺服系统以及多个同步任意波形的生成。
