How fast resolution could I get using 12 bit ADC?

jayy — Mon, 01 Oct 2012 18:04:36 GMT

Hello everyone,

How fast could I get the ADC conversion time from 1800 sensor using 60 GPIO pins and 30 ADC pins?

I am sensing analog signal from 1800 points using 12bit ADC in MK60DN512ZVLQ10 Microcontroller.

It takes little over 170ms now, but from the datasheet Min 20 Ksps(1800 / 20 K = 90ms) ~ Max 818.330 Ksps(1800 / 818.330 K = 2.2ms).

I am using MQX too.

I need 5 ms resolution. Is is possible to get the result with MK60DN512ZVLQ10?

If not, do you have other microcontroller to get this resolution?

Re: How fast resolution could I get using 12 bit ADC?

apanecatl — Wed, 31 Oct 2012 17:19:53 GMT

Hi Jayy

First I'd like to know a couple of things about your project:

1) If you sampling1,800 different sensors sensors,

How are you reading all of them using only 30 ADC channels?

How are you multiplexing the signals?

2) If you are indeed multiplexing the signals you must take into consideration there will be a delay between readings,

slowing down the total mount of time necessary to perform the readings and conversions

3 If you are reading 1,800 consecutive samples instead of reading 1,800 different signals you can easily get the

conversion time you are looking for, please ellaborate, your statement is not clear enough.