- #1
tomizzo
- 114
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I am currently working on a circuit design that is featuring both a ADC and DAC. I'll focus my question on the ADC in this thread.
I'm trying to figure out what each pin does. Am I correct in assuming that the Vref pin on the an ADC chip is used as the maximum encoded value for a voltage? Say for example I have an ADC capable of encoding a 0-5V signal with 8 bits of resolution. And then say that I only want to be measuring a maximum voltage of 2V. If I were to tie 2V to the Vref pin, this should scale the encoded values 0-255 to correspond with voltages from 0-2V. Correct?
However, I noticed on a recent data sheet that the sample rate of the ADC is dependent on the value of Vref (see image below). Why is this? Why would the sample rate depend on what is set to the Vref pin?
Any help regarding this?
I'm trying to figure out what each pin does. Am I correct in assuming that the Vref pin on the an ADC chip is used as the maximum encoded value for a voltage? Say for example I have an ADC capable of encoding a 0-5V signal with 8 bits of resolution. And then say that I only want to be measuring a maximum voltage of 2V. If I were to tie 2V to the Vref pin, this should scale the encoded values 0-255 to correspond with voltages from 0-2V. Correct?
However, I noticed on a recent data sheet that the sample rate of the ADC is dependent on the value of Vref (see image below). Why is this? Why would the sample rate depend on what is set to the Vref pin?
Any help regarding this?