English

OLIA: an open-source digital lock-in amplifier

Signal Processing 2023-04-13 v2

Abstract

The Open Lock-In Amplifier (OLIA) is a microcontroller-based digital lock-in amplifier built from a small number of inexpensive and easily sourced electronic components. Despite its small credit card-sized form-factor and low build-cost of around US$35, OLIA is a capable instrument that offers many features associated with far costlier commercial devices. Key features include dual-phase lock-in detection at multiple harmonic frequencies up to 50 kHz, internal and external reference modes, adjustable levels of input gain, a choice between low-pass filtering and synchronous filtering, noise estimation, and a comprehensive programming interface for remote software control. OLIA comes with an optional optical breakout board that allows noise-tolerant optical detection down to the 40 pW level. OLIA and its breakout board are released here as open hardware, with technical diagrams, full parts-lists, and source-code for the firmware provided as Supporting Information.

Cite

@article{arxiv.2211.08889,
  title  = {OLIA: an open-source digital lock-in amplifier},
  author = {Andrew J. Harvie and John C. de Mello},
  journal= {arXiv preprint arXiv:2211.08889},
  year   = {2023}
}
R2 v1 2026-06-28T06:02:14.672Z