Im building a dual-slope ADC for a university project which needs to run on +12V and 0V supply.
Vin can range from 100 uV to 2 V.
I have read up about the integrator circuit and think I know how it works. Using the Vout = 1/RC|Vin.dt formula have calculated the RC values.
I have a couple of problems though:
How do I create the negative Vref voltage with only 0 and 12V? Charge pump type circuit? or maybe bias the voltage regulator?
How do you determine what size R and C should be? eg 1uF & 22k or 1nF & 220k ect does it even matter?
How do I build the digital switch shown in the diagram? Multiplexer from a few FETs?
Vin can range from 100 uV to 2 V.
I have read up about the integrator circuit and think I know how it works. Using the Vout = 1/RC|Vin.dt formula have calculated the RC values.
I have a couple of problems though:
How do I create the negative Vref voltage with only 0 and 12V? Charge pump type circuit? or maybe bias the voltage regulator?
How do you determine what size R and C should be? eg 1uF & 22k or 1nF & 220k ect does it even matter?
How do I build the digital switch shown in the diagram? Multiplexer from a few FETs?
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