I want to use a 1010 powered by the USB on a board designed for the Mega. Plan to connect Gnd and other IO to pins on the board for a Mega via wire wrap.
Need to read MAX147 ADC's via SPI. Is the output of the MAX147 which is powered at 5v to the MISO a problem? https://datasheets.maximintegrated.com/en/ds/MAX146-MAX147.pdf
The board also has some digital inputs pulled up with 4.7k to 5v and a 1-Wire string of DS18S20 pulled up to 5v. Is that dangerous to the 1010?
The 1010 also needs to drive a ULN2803 directly from IO pins. https://www.st.com/content/ccc/resource/technical/document/datasheet/e4/fa/1c/16/4e/39/49/04/CD00000179.pdf/files/CD00000179.pdf/jcr:content/translations/en.CD00000179.pdf
The reason the board must be run at 5v is that it has a number of relays with 5v coils that call for 3.5v to operate. It has its own 5v power supply and reference for the MAX147 ADC.
Is there anything I may be missing?
Thanks in advance.