MCP4725 digital to analog converter + I2C

I just bought 2 Sparkfun Breakout Boards for MCP4725 DAC which communicate via the I2C bus.

This link made me understand how to use MCP4725 digital to analog converter: http://blog.michaelbparks.com/2008/09/sparkfun-dac-breakout-board-tutorial_8918.html

datasheet here: http://www.sparkfun.com/datasheets/BreakoutBoards/MCP4725.pdf

The DAC MCP4725 has a 12bit resolution, which allows for 4095 steps, 0 - 5 volts.

Unfortunately I was not able to use more than one MCP4725, since the breakout board had the external address pin A0 tied to Vss. If it would not be tied to anything then one DAC could use address 0 (A0=Vss) and the other address 1 (A0=Vdd).

Source Code here: http://maybevideodoes.de/howto/DAC/i2C_MCP4725.pde

Cheers, Stephan Schulz / www.maybevideodoes.de

more than one MCP4725, since the breakout board had the external address pin A0 tied to Vss

You can always use an analogue switch(s) to route the I2C data line to the relevant device.

just wanted to add something.

mcp4725 has pin A0 if tied to Ground one should use Wire.beginTransmission(96);

but if A0 is tied to +5V one should use Wire.beginTransmission(97);

this allows us to use two DAC on the same i2C line.