This repository contains the design of a digital controller for laser frequency 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 'lockbox' feature of the software package PyRPL.
The controller features:
- Bandwidth of 1.25 MHz
- Two independent control loops (e.g. laser current and piezo)
- Fast output (-1 to 1 V) e.g. for laser current
- Low-noise piezo output
- Voltage range: ± 10 V / 250 mA
- Variable analog piezo offset (± 10 V)
- Error signal input stage with optional amplification via hardware adjustment
- Buffered monitoring outputs for piezo output and error signal input
- Integrated 5 V / 2.5 A power supply for the RedPitaya 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. / 1.4 A max.)
- - 15 V (0.1 A typ. / 0.5 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.