(i have posted this on another forum section too, i wasnt sure which forum would be right for this, even though this is a project)
I'm working on a project where i have to build a 4 bit dual slope adc.
So far i have figured out everything but looping it...
I have attached what i ve done so far for generating the pulse and connecting the binary counter and decoder and getting out the digital output through a 7segment display.
(input to the clamp comes from the comparator)
i need to loop this now.. like back and forth from v ref to v in.
and the worst part is, i have to use bjt as a switch and/or comparators to loop it.
If i am right-- the logic goes like this:
if you get 1111 out of the binary counter, then you want to switch to v ref--
therefore i get v ref from the capacitor discharge. Ones the capacitor has fully discharged, the number left in the 7segment display is the digital output. at this point v ref is 0, therefore i have to switch back to v in, and so on it loops...
i am utterly confused with this looping.. i can get an and gate to tell me if all are 1s in the output of my binary counter.. but then what..? i can get the discharge of the capacitor as v ref through a bjt then what..? how will i connect the dots..?
help me!!
Thank you.
Sean
I'm working on a project where i have to build a 4 bit dual slope adc.
So far i have figured out everything but looping it...
I have attached what i ve done so far for generating the pulse and connecting the binary counter and decoder and getting out the digital output through a 7segment display.
(input to the clamp comes from the comparator)
i need to loop this now.. like back and forth from v ref to v in.
and the worst part is, i have to use bjt as a switch and/or comparators to loop it.
If i am right-- the logic goes like this:
if you get 1111 out of the binary counter, then you want to switch to v ref--
therefore i get v ref from the capacitor discharge. Ones the capacitor has fully discharged, the number left in the 7segment display is the digital output. at this point v ref is 0, therefore i have to switch back to v in, and so on it loops...
i am utterly confused with this looping.. i can get an and gate to tell me if all are 1s in the output of my binary counter.. but then what..? i can get the discharge of the capacitor as v ref through a bjt then what..? how will i connect the dots..?
help me!!
Thank you.
Sean
