

Member level 1
adc working
In the world, there are three catagories of ADC. I would like to ask what is the working principle of the successive approximate ADC. I get the block diagram but I don't understand the working principle...
thx:)

21st May 2007, 12:38

Full Member level 3
adc working principle
From this time diagram you can see basic idea. First you test MSB (100000), if it is less than Vin, then MSB=1 else MSB=0. Then you test MSB1 (110000) from the pisture you can see that it is greater than Vin, so MSB1=0 (100000). Than you test MSB2 (101000) from picture it is equal, but you need to test rest of the bits. And so on, and so on.....

21st May 2007, 13:25

Advanced Member level 5
successive approximation principle
the working principle is that you set the MSB as 1 and convert it to analog and compare it with the input and if the input is larger than this generated value then it is obvious that the MSB is 1 else it is 0... so you have found the MSB... now u keep the MSB as such and then find MSB1 place and then so forth.....

31st May 2007, 14:56

Full Member level 6
adc working
Look through AN 1080 from Maxim
"Understanding SAR ADCs"
http://pdfserv.maximic.com/en/an/AN1080.pdf