Interfacing ADC

[dark]

Can this ADC MCP3551

**broken link removed**

which is a differential input ADC be used as single-ended ADC with -ve Grounded .

Thanks

 

[MikeMl]

According to the data sheet fragment, it looks like it will work as long as both inputs are constrained to be between Vss and Vref.

 

[dark]

According to the data sheet fragment, it looks like it will work as long as both inputs are constrained to be between Vss and Vref.

Mike, I am still bit confused the spec you have attached says regarding differential input and nothing regarding the single ended conversion .Say in the case of MCP3421 it says regarding single ended wiring for ADC.

 

[Mikebits]

Why are you opposed to a differential input? This will keep your system more noise free. Otherwise, why not use a simpler ADC?

 

[dark]

Why are you opposed to a differential input? This will keep your system more noise free. Otherwise, why not use a simpler ADC?

Mike, we already source from Microchip ,therefore its easy to choose their products. In my application I am getting conditioned 0~5V single ended signal and need to know if this is doable with the above ADC .

 

[MikeMl]

Try powering it from 5V; Vref to 5V, Vss=0V, Vin-=0V. Feed input to Vin+. If you use your 5V logic supply for Vref, you will be lucky to get 12bits noise free. To get over 12bits, you will have to use differential input and a very clean Vref.

 

[dark]

Thanks Mike , I feel it would be of no use in single ended application with 12bits .

 

[Mikebits]

Mike, we already source from Microchip ,therefore its easy to choose their products. In my application I am getting conditioned 0~5V single ended signal and need to know if this is doable with the above ADC .

Have you determined the minimum noise output of your sensor? Is it small enough to require a high res ADC? If the sensor noise floor is substantially greater than the ADC resolution, then you can get away with a lower res ADC part. I am sure Microchop has a large selection of parts.