High speed AD converter, IC selection help

Hi

In the process of selecting a external ADC. My aim is to reach above 200ksps (min 8bit), anyone have an earlier good experience with any ADC IC? Would this speed be able to manage over spi or i2c?

Thanks in advance!

Would this speed be able to manage over spi or i2c?

With i2c no way since it runs at a 400Khz bit clock. SPI maybe, with the right processor. Not with the arduino since there is no room to store your samples in RAM and you have no resources left to to write your data to external RAM.

Eberhard

Thanks Eberhard

So this said, a little bit as I assumed and read here at the forum, there is not so many options on arduino to increase the AD conversion capability internal or external, except decreasing the prescale factor to 16 and obtain around 30-40ksps?!

I don't know much about the topic beyond the qestion about i2c/spi bus-speed

This guy here seems to have dug deeper ... http://sites.google.com/site/measuringstuff/the-arduino

Eberhard

Eberhard, this is a most entertaining link to a well written article you posted, alas it contains no information other than already in this thread here, except of course a lot of demo code…

@krst Remember than a complete Arduino chip costs less than any medium quality ADC alone :slight_smile:

Yes, from a price point of view I have to agree. I am also looking into the netduino, maybe in native code this unit should be able to reach these samplings speed (at least states around 400ksps in the spec of the chip).

And thanks for the link Eberhard, I have seen this nice page before, and was able to increase the speed with the prescale.

My aim is to read a linear immage array, there are only 300pixels in each image frame, but i want to be able to take around >600 frames a second and there is where I want the high sampling speeds. I am making a laser ranger and i want to make a 180deg sweep more than once a second… I have some options on maxim ic (~20$), that has a conversion rate around 1us but then comes the problem with comunications to the ARV… I guess I can only dream about achiving these speeds but was hoping that maybe someone have tried something like this out by using spi :slight_smile: