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View Full Version : Sharp GP2D12, ADC0831, and the Propeller - What to buy?



russ christensen
03-20-2009, 10:42 PM
Hi, I found out recently that I need an A/D converter to be able to use the GP2D12 Infrared Distance sensor. These A/D converters, the ADC0831, cost 6 bucks apiece at Parallax, and i would need one for every sensor i have. That much I understand. My question though, is there a multi-input, ADC that would work as well, so i could have one chip handling up to 6 or 8 GP2D12's? Thanks in advance!

Russ

Post Edited (russ christensen) : 3/20/2009 8:14:43 PM GMT

Mike Green
03-20-2009, 10:49 PM
There are many multi-input ADCs. The ADC0834 is a 4-input ADC in the series and the ADC0838 is an 8-input ADC. Although there are details that are different among them, they're built on the same ADC platform.

The Propeller can do multiple ADCs if you have enough I/O pins available (2 per channel).

Look in the Object Exchange for existing drivers for different ADCs. They're in the Sensor section of the ObEx.

Post Edited (Mike Green) : 3/20/2009 3:54:42 PM GMT

virtuPIC
03-21-2009, 12:09 AM
Well, I've got the impression that Microchip's MCP3208 (8 channels, 12 bit) is widely used by forum members.

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virtuPIC
03-21-2009, 12:25 AM
...oh, I forgot. MCP320x ADCs are comparably inexpensive. aND on www-microchip.com (http://www-microchip.com) you can also order free samples.

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www.airspace-v.com/ggadgets (http://www.airspace-v.com/ggadgets) for tools & toys

russ christensen
03-21-2009, 02:10 AM
All of these are compatible with the sharp sensor? Just wanna make sure before i order one. Thanks for all the info!

Russ

russ christensen
03-21-2009, 03:13 AM
I edited the title. I found the ADC0838 for sale on a web page for just over a buck fifty, but here's the problem, they have a minimum order of $35 bucks. What else should i buy? anything interesting i can add to my order? they don't have a plain catalogue so i have to know the part number. any suggestions?

Edit: guess i should tell you guys the website
http://www.onlinecomponents.com/

virtuPIC
03-21-2009, 04:15 PM
I am still advertising Microchip's MCP3208 (http://www.microchip.com/wwwproducts/Devices.aspx?dDocName=en010534). You can run it at the same supply voltage as the prop. If input voltage range is too low you can simply use a voltage divider made from two resistors. If it is too large you can simply drop some MSBs since you probably won't need full resolution anyway.

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Airspace V - international hangar flying!
www.airspace-v.com/ggadgets (http://www.airspace-v.com/ggadgets) for tools & toys