ADC - is many analog signals measure in time possible?

[bigplik]

hi,
just wonder if is it possible to measure few low signals by teensy LC or teensy 3.2,
I read that teensy 3.2 can make only 2 measurements at one time (2 ADS)
but if I make some small delays (eg. 50ms) between measurements and put that in one function,
then make longer loop would that work and I can read 4 or more low signals?

I also would like to find out about gain function in teensy 3.2,
is it possible to gain more than 2 signals if I make code similar to idea I wrote above?

 

[Epyon]

Teensy 3.X can read 10 analog signals (20 if you also use the backside pads). See the reference schematic, all pins in light pink can be used.

What you are referring to are the two ADCs in the Teensy. Teensy can only read two signals simultaneously. But these two ADCs are multiplexed over the analog pins. E.g. if you read analog pin A0, a few ms later you read A1, then A2 etc. the ADC will switch between and read those pins. There will be a small delay between reads like you describe, but you don't have to code that yourself.

You can also do consecutive simultaneous or differential reads, but only on a few pins (16 (A2), 17 (A3), 34-36 (A10-A13)). See pedvides ADC library.

 

[bigplik]

Teensy 3.X can read 10 analog signals (20 if you also use the backside pads). See the reference schematic, all pins in light pink can be used.

What you are referring to are the two ADCs in the Teensy. Teensy can only read two signals simultaneously. But these two ADCs are multiplexed over the analog pins. E.g. if you read analog pin A0, a few ms later you read A1, then A2 etc. the ADC will switch between and read those pins. There will be a small delay between reads like you describe, but you don't have to code that yourself.
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thanks for an info

do you know anything about PGA/signal gain? how to use it? my signals are sometimes less than 10mV, would like to read several of them,
small delay isn't a problem in this case,
is it possible to use gain for more reads? in the way you described? I mean with some delay?

 

[Pedvide]

The ADC library has support for PGA. But PGA only works for the differential pins A10-A11, A12-A13 (and only for Teensy 3.1/3.2).

 

[gofaster]

The ADC library has support for PGA. But PGA only works for the differential pins A10-A11, A12-A13 (and only for Teensy 3.1/3.2).

And only with the internal 1.2V reference.

 

[Brooks]

my signals are sometimes less than 10mV

Consider amplifying the signal before applying it to the Teensy. As a digital environment 10 mV is probably in the noise.