Embedded ADC with external Signal Conditioning

[cdanderson04]

Hello all:

This is my first post on the physics forum so I am excited to have found such a great community of scientists.

My problem is that I have been looking for an embedded board that contains an ADC but has a very good external signal conditioning stage. This will be for a data acquisition and the signal will be an analog, small range, voltage, most like 0-5V. I have been doing some research on Analog Devices and they have everything in a chip. I was looking for a more module like board. The ability to change the parameters in case the analog input changes would be great. For example the range is just 0-1V.

Any help that anyone could possibly provide would be greatly appreciated.

Thanks in advance.

 

[ranger]

Lots of these systems will have the ADC in a chip. They are called SoC (System-on-chip) and you should be really using those to do your design. But if you want an ADC module outside of your chip, then you need to purchase a ADC IC and interface that to the inputs of your uC. Here you have some flexibility to choose the precision, whereas SoCs may put an upper limit on the precision.

Maybe others may be able to suggest boards.

 

[cdanderson04]

Yeah. That is pretty much what I wanted to, but I wanted the signal conditioning outside of the chip.

So pretty much I want.

Sensor input > signal conditioning > ADC > micro-controller

Thanks for the input!

 

[berkeman]

Yeah. That is pretty much what I wanted to, but I wanted the signal conditioning outside of the chip.

So pretty much I want.

Sensor input > signal conditioning > ADC > micro-controller

Thanks for the input!

Have you looked at the National Instruments line-up?

http://www.ni.com/dataacquisition/

They have lots of different form factors and interfaces for ADC boards and modules.

There's also Omega:

http://www.omega.com/das/

.

 

[cjameshuff]

Lots of these systems will have the ADC in a chip. They are called SoC (System-on-chip) and you should be really using those to do your design. But if you want an ADC module outside of your chip, then you need to purchase a ADC IC and interface that to the inputs of your uC. Here you have some flexibility to choose the precision, whereas SoCs may put an upper limit on the precision.

Well, aside from offering more flexibility in selection, an external ADC allows some greater degree of immunity to noise from the microcontroller itself. Some microcontrollers can be put into a partial sleep state during conversion to minimize such noise, but an external converter could be put on a completely separate, well-filtered power supply, and could also perhaps be located closer to the signal source. It also gives you more room for future changes...it's easier to switch to a different ADC (or add another one) than it is to move to a different processor if it proves not to meet your needs.

If a really high quality ADC and analog section are what you want, you would probably be better off picking a uC you're familiar with or can more easily get tools for, and hooking it up to external components that suit your needs. If low cost/low complexity/compactness are higher priorities, a uC/DSP/SoC with an adequate on-chip ADC and analog front end is probably a better bet. It really depends on what you're trying to do...