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Single supply ADC driver Op amp

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jon-ecm

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Hi guys, I'm working on an ADC fronted for a new hobby project and was looking for some helpful advice on whether my circuit will work or not.
I understand that the op amp will not swing to absolute 0 and that there will be some missing codes but other than that, is this circuit going to work? Is it ok to use one ground for both VEE and the Common Mode, The ADC datasheet says it's rated for that but I've never done it before and would love some expert advice,

Datasheet for Op-Amp https://datasheets.maxim-ic.com/en/ds/MAX4434-MAX4437.pdf
Datasheet for ADC https://www.ti.com/lit/gpn/ads8330 The Input capacitance for the ADC is 40pf

That being said I'll post the schematic
opamp.png

Thanks!

Jon
 

kender

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Jon, what is the purpose of the voltage divider R2,R10? Can you reduce the gain of the first OpAmp instead?
The output of the first OpAmp has low impedance, so you can connect it directly to the ADC.

- Nick
 

jon-ecm

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the 100 ohm is just an isolation resistor so the amps don't oscillate from the capacitance in the ADC (40pf), also the vref on the adc is 4.096 so I have to cut down the voltage a little so it doesn't get damaged that's what the 1k is about

I understand about the first op amp having low impedance but I have the second one is there in-case I wanted to increase the gain higher without limiting bandwith. On my actual I pcb I have the spots for the feedback and gain resistors but it's just bridged right now in a buffer configuration like shown above.

but putting that aside, as far as the circuit goes, do you think it is going to work?

Jon
 
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