Hi All!
I'll try and not rabble on too much, but just to give some back story.
I had a plan to use the MCP3551 to measure a 1V voltage between 2-3V. I needed the finest resoloution I could get, so had planned to bias the MCP3551. I thought I had this in my head, however when I went to datasheet to start laying things out for the PCB, I realised I had probably made an error.
I've attached the block diagram of the MCP3551.
So my plan was to connect both a 3V and a 2V reference to the MCP3551, which should give the detail I want (or at least would on a standard ADC with with a Vref and a -Vref).
When I realised the MCP3551 was built differently to what I expected, I realised this probably wouldn't work, but the connections I have are as follows.
Vin- : To 2V reference.
Vin+: Actual voltage input.
Vref: 3V reference.
I know now that I've read the data sheet, that I'll lose the negative half of the 22bits, but will the above connections give me the top half at least? If not, what is the correct way to use the MCP3551 as a "standard" ADC with a negative and positive Vref?
I have gone through the datasheet, but I'm just not getting it! Sorry.