FPGA-based Low-Latency Digital Servo for Optical Physics Experiments
Marco Pomponio, Archita Hati, Craig Nelson
We propose a general-purpose dual-channel field-programmable gate array (FPGA) based digital servo with a minimum latency around 200 ns. This servo implements a proportional, dual- integration and derivative (PIID) controller along with internal numerical controlled oscillators (NCO), a phase detector (PD) utilizing a fast in-phase and quadrature (I/Q) detection algorithm (80 ns), NCO modulator, network analyzer, auto-locker, ramp generator, and low pass filters. A web interface and/or python commands over TCP/IP allows full control and monitoring. The servo has been successfully used to lock Pound-Drever-Hall cavities, phase- locked loops and optical frequency combs. A simple experiment phase-locking two dielectric resonator oscillators (DRO) has been set up to demonstrate a 1 MHz closed-loop bandwidth.
, Hati, A.
and Nelson, C.
FPGA-based Low-Latency Digital Servo for Optical Physics Experiments, IEEE IFCS-ISAF 2020 Conference Proceedings, Keystone, CO, US, [online], https://doi.org/10.1109/IFCS-ISAF41089.2020.9234889
(Accessed June 5, 2023)