8-Channel Analog to Digital Converter 12-Bit + 8-Channel Digital IO + 8-Channel Open Collector with I2C Interface power consumption?

I’m looking at this board and was wondering about the power consumption when powering it with 5V via the I2C port.

# 8-Channel Analog to Digital Converter 12-Bit + 8-Channel Digital IO + 8-Channel Open Collector with I2C Interface

Another question:
is there a board like this but with 4 ADC inputs and 4 digital IO’s by any chance?


Hi @gusgonnet,

Good to hear from you. I hope you’re doing well.

I will try to get a hold of one of these to check power consumption, however the largest power draw components on the board are going to be the ULN2003 and the MCP23017, if you add their power consumption ratings together you will be very close to the board’s overall power draw.

Thank you,
Travis Elliott

all good! I’m happy to land a project that can use one of these cool boards.

thanks for the tip, Travis, hope you are doing well too.

Hey Travis, I need a little push if you do not mind. Is this the right parameter I should be looking at for the power consumption of the MCP23017?
My plan is to use it all as inputs.

I would look at section 1.0. Looks like the maximum current into Vdd pin is 125mA. That would(I assume) be at the lowest possible supply voltage of 1.8V so overall wattage would be 0.225. Our board powers the MCP23017 at 5VDC so the current consumption at 5VDC would be a maximum of 45mA.

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Hey Travis @TravisE_NCD_Technica ,
Is the I2C bus on this board 5v or 3v3?
Is there a setting that I can use to select either?

Hi Gus,

The board is powered by 5VDC. The MCP23017 could be powered by the I2C bus at 3.3VDC but to be honest I’m not sure about the ULN2003. I don’t know if it could be powered by 3.3VDC or not.

If you supply power via the 2.1mm barrel connector then an on board regulator will supply power to the ICs at 5VDC so you should be careful directly connecting it to the I2C master. If you are not using an I2C interface adapter we sell and the I2C master is only 3.3VDC tolerant that could damage the master.

I’m not worried about the ULN2003 since I’m not planning on using it, also I’m reading this:

Both the MCP23017 and the ADS7828 seem to be able to work with 3V3.

So the question is: if I power the board from the I2C bus with 3v3, do I have chances it works?
I can’t find a schematic of the board (is there one somewhere?) so I can’t check what happens with the 5V I2C input, if it goes directly into the ICs or if there is a regulator or something else.
Thanks again!

power the the board using 3V3 ( using I2C port) and set the power jumper to Bus.


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