Fastest ADC in the Arduino World - Page 1
Forum section: electronics / general

author: ats3788
author_rank: Contributor
timestamp: January 04, 2024, 02:27:18 pm
content: HelloWhat is the fastest ADC in the Arduino World ?I fiddle with the ADS1115 and MCP3421 but it would be nice to fiddle with a faster Controller.

author: Kleinstein
author_rank: Super Contributor
timestamp: January 04, 2024, 02:47:40 pm
content: If it is just about fast the µC internal ADCs are aready quite a bit faster, but lower resolution. With the AVR based one this should be some 16 kSPS at 10 bits and maybe 8 bit performance up to some 70 ksps.With the Arduino typical overhead this is about as fast as the SW side can do much with the result.It gets quite a bit faster with ARM based Arduino versions: they may offer 12 bits up to some 2 or 5 MSPS depending on the chip used.

author: dobsonr741
author_rank: Frequent Contributor
timestamp: January 04, 2024, 03:08:50 pm
content: Why do you need a faster converter? Consider what you’ll be doing with the volume of data a faster ADC dumps at you.

author: MasterT
author_rank: Frequent Contributor
timestamp: January 04, 2024, 04:16:41 pm
content: My recent finding is nucleo-G474re (form factor arduino and could be programmed under arduino IDE):11.2 MSPS when adc overclocked. Thare are 5 internal adc, so theoreticallly 56 MSPS.It's only uCPU in stm32 world that have adc with such high speed, others usually can't be drivven above specified ~5 MSPS, even 480 MHz core H7 series.

author: ats3788
author_rank: Contributor
timestamp: January 05, 2024, 01:00:21 pm
content: Why Why Why, because we are Hobby tinkerer and I would like to sample a 50Hz Wave properly The ADS1115 with its ADS1115_860_SPS is almost OK. 2k SPS would be perfect faster even better. Faster then 2K is not necessary.Thank you for the answers anyway.

author: iMo
author_rank: Super Contributor
timestamp: January 05, 2024, 01:35:43 pm
content: You have to look for an SPI ADC with 16bit resolution (as your 1115 is 16bit, mind its ENOB at 860Sampl/sec is lower), and the required sampling rate.For example I have an SAR MAX11166/67 in my junkbox gathering dust for ages, those are 16bit, SPI, max 250/500K Sampl/sec with true bipolar inputs (+/-5V max).There are tons of other ADCs with such params available (except they are usually not with true bipolar inputs).PS: also mind many sigma delta ADCs have got a notch filter at 50/60Hz, no idea how it may interfere with your intention to measure 50Hz signal, however..

author: Kleinstein
author_rank: Super Contributor
timestamp: January 05, 2024, 02:09:17 pm
content: The 50/60 Hz notch with SD ADC is only present with the slower conversion rates, like 50 SPS and less. They include a digital low pass filter by design as part of the ADC function and with the low conversion rates it helps to suppress main hum to have a zero at the mains frequency. Of cause this no longer works with faster conversions.For the speed / bandwidth the difference between SD ADCs and SAR types (e.g. the usual µC inernal ones) may be relevant:The SD ADCs are averaging over some time and doing low pass filtering. They don't need much extra AA filtering.With SAR ADCs the input sampled for a rather short time and one can thus get aliasing from higher frequencies. If a classic AA filter is used the usable BW will be lower than the Nyquist limit and usually the BW a SD ADC can use at the same sampling rate. If no AA filtering is used, one will also get parts from higher frequencies - this may be bad (extra noise from aliasing) or good e.g. with subsampling to include higher frequencies in RMS readings.

author: MarkT
author_rank: Frequent Contributor
timestamp: January 06, 2024, 02:34:07 pm
content: I've interfaced to an ADS8885 on the Teensy 4.0. That chip is an SAR ADC, 18 bit, upto 400kSPS.

author: ats3788
author_rank: Contributor
timestamp: January 07, 2024, 10:17:44 am
content: Thank, you very much iMo and Kleinstein, MarkT sound good. Check it out

author: ats3788
author_rank: Contributor
timestamp: January 07, 2024, 02:09:21 pm
content: ok, I admit defeat, the esp32 has a sampling rate that is fast and reasonably accurate Thank you Forum

author: spam_4_tea
author_rank: Newbie
timestamp: August 13, 2025, 10:05:51 am
content: this the STM32G474RE MCU?I need ENOB 10 bits to keep up with video clocked at max 2Mhz - one of 8 channels at a timeWas looking at the MAX19777 with a 4 or 8 way MUX.How do you find the noise / ADC range on the STM32G474RE? I am decoding video from a S13131-1536 image sensor - could run it slower if need be at 1Mhz

author: iMo
author_rank: Super Contributor
timestamp: August 13, 2025, 10:18:51 am
content: 10bit enob with an stm32 at XMsamples/sec would be rather challenging exercise, imho. It depends on the pcb design, using internal/external Vref, using internal/external clock, quality of power supplies, impedance of the signal source, etc. Typical noise levels I saw with stm32f1xx, stm32f3xx, stm32f4xx at much lower sampling rates and ebay pcbs were 6-8 counts peak-peak..