Biquad Filters (DSP with STM32) - Phil's Lab #172

Theory and implementation of digital, discrete-time biquad filters on an STM32-based audio-processing system. Limited-time: $2 for 6-layer PCBs up to 100×100 mm - grab your $33 coupon now: https://jlcpcb.com/events/6-layer-pcb... (Ad) OSHWLab Stars 2026: https://oshwlab.com/activities/stars2026 Altium Develop: http://altium.com/yt/philslab (Ad) [SUPPORT] Hardware design courses: https://phils-lab-shop.fedevel.education Course content: https://www.phils-lab.net/courses Patreon:   / phils94   [LINKS] DSP Playlist:    • DSP   [TIMESTAMPS] 00:00 Intro 02:02 JLCPCB (Ad) 03:37 Altium Develop (Ad) 04:42 Basics 07:02 Why use Biquads? 08:35 Transposed Direct Form II 09:58 Difference Equations 12:58 Computing Coefficients 15:33 Implementation 23:09 Lowpass Filter Test (2nd Order) 24:47 Cascading Biquads (4th Order LPF) 25:59 Outro