24-Channel Digital Input/Output with I2C Interface šŸ”3.3v

Hardware
1

Hi,

I have a few of these boards in stock, need to convert to 3.3V support
What do I need to do?

Thanks,
Jeff

2

Hi Jeff,

What are you connecting the board to(What is the I2C master device e.g. Raspberry Pi)? Are you using one of our I2C interface shields on the Master Device?

Thank you Jeff,
Travis

3

Hi Travis

IO is connecting to 3.3v logic on the UUT
I2C is going back to a PC using a USB<->I2C adapter
older version of this:
#I2C Converter with Dual Serial to 8-Port Hardware I2C

Thanks,
Jeff

4

@Bhaskar,
Would it be possible to switch this device from Bus power to Ext power, and supply it with 3.3VDC through the power supply screw terminals or 2.1 mm barrel? Would that make the Digital output channels from the MCP ICs output 3.3VDC instead of 5VDC? Iā€™m not sure if the MCP ICs were powered by 3.3VDC and the SDA and SCL lines were receiving data at a 5VDC level from the USB to I2C converter if that would damage the MCP ICs or not.

5

Yes, its possible to make the IO 3.3V.
You will have to send these units back for modification.

I would recommend sending the device in for RMA repair. You can do that by filling out this RMA form and shipping the device back to us(instructions for returning the item long with an RMA ID will be emailed to you after completing the RMA form):
https://ncd.io/contact-us/product-returns/

In the RMA note include " modify device for 3.3V IO see Bhaskar"

For future ref you can mention this while placing the order and device will be modified to work at 3.3V.

Thanks