Cheap ADC and other boards

Post Reply
Posts: 1320
Joined: 10.07.2012, 04:00
Location: Texas, USA

Cheap ADC and other boards

Post by Richard-TX » 13.12.2013, 08:32

There are some cheap (< $2) PCF8591 4 channel ADC boards available on Ebay. The downside is that the address lines are all tied low (0x48) I have successfully lifted the SMD pins and tied them high to attain other addresses.

For less than what I can buy the chip for, I can have a board with the chip mounted.

The 3 jumpers connect a pot, light sensor, and a temp sensor to 3 of the ADC inputs. Simply removing the jumpers disables those components.

Do a search for "PCF8591" and you will find them.
$1.91 - free shipping

I have also found some reasonably priced I2C bus expander/multiplexer boards. It uses the PCA9544A chip from TI which costs about $3 in single lots quantities from Digikey. That means that you are buying the board and having the chip mounted on it for $4.

Data sheet at

It is at



Post Reply

Return to “DIY Hardware”