Q: What is the STM32 ADC configuration for multi-channel sampling at high accuracy?
Answer
For multi-channel ADC with high accuracy: use independent power supplies (VDDA/VSSA) or at minimum filter VDDA with LC (10 uH + 10 uF) for analog section isolation. Use DMA in circular mode with a buffer sized to (channels x oversampling factor). Configure scan mode with DMA circular to automatically scan all channels. For 12-bit resolution allow sufficient ADC clock (<=14 MHz on most STM32) to meet programmed sampling time. Calibration: call HAL_ADCEx_Calibration_Start() before first conversion. For simultaneous dual-ADC sampling (STM32F3/F7/H7) interleave channels and use the higher combined sample rate. Average over multiple samples in software to improve effective ENOB.
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