This repository contains the design of a digital controller for laser intensity stabilization based on the RedPitaya STEMlab 125-14 board. The design includes schematics and readily usable PCB layouts for an analog interface integrable in standard 19-inch rack mount units using the available front panel. We recommend to use the controller with the 'pids' module of the software package PyRPL. The devices features two independent, identical channels using only one Red Pitaya board.
The controller features:
- Two independent channels for laser intensity stabilization
- Control bandwidth of 1.25 MHz
- Photodetector input with variable gain
- Gains (1,2,4,8,16) selectable via front panel DIP switch
- Gain bandwidth product: 35 MHz
- Reference level input
- Digital sample and hold with 150 ns delay
- Buffered control outputs
- Max. current: 30 mA
- Gain bandwidth product: 35 MHz
- Buffered monitoring outputs for photodetector signal and error signal
- Integrated 5 V / 2.5 A power supply for the Red Pitaya board
The design files can be found on the releases page and include the following resources:
- Schematics as a PDF
- Gerber files
- Pick & place position files
- Bill of materials as a CSV file and also as an interactive HTML version
The latest revision of those files can be found here.
Review of Scientific Instruments 91, 083001 (2020); https://doi.org/10.1063/5.0009524
arXiv:2009.00343 [physics.ins-det]; https://arxiv.org/abs/2009.00343
T. Preuschoff, Laser Technologies for Applications in Quantum Information Science, Ph.D. thesis, TU Darmstadt, 2023, https://tuprints.ulb.tu-darmstadt.de/23242/
- RedPitaya StemLab 125-14 board: Remove the noisy DC-offsets.
- Dual power supply
- +15 V (0.4 A typ. / 1.0 A max.)
- - 15 V (0.1 A typ. / 0.15 A max.)
- 19-inch rack mount unit (e.g. Fischer Elektronik BGT384)
- TCP/IP network and control computer
This work is released under the CERN OHL v.1.2 See www.ohwr.org/licenses/cern-ohl/v1.2 or the included LICENSE file for more information.