Hello,
Let me Explain my problem here.
there are 16 thermo couples, I have to read all the 16 values and I have to store it in memory.
Each 4 thermocouples are connected to one cd4052 multiplexer and it's output is connected to lmp90100
Like this totally 4 CD4052 multiplexers output is connected to lmp90100.
And now we are using Vref as lm4140-4.1v output.
As i already told you we have to measure Thermocouple voltage. But This will be voltage in milli volts, of course some times it will be micro volts for some other thermocouples type.
Why I am telling this is we have to measure micro volts.
Firstly I am measuring ch0 ---> vin1-vin0
next Ch0 ----> vin3-vin2
next ch0 ----->vin5-vin4
at last ch0----> vin7-vin6
Like this i am reading values.
here how much time gap i have to give for each reading.
And while i am not connecting any input to one of the channel and if i tried to read that channel some times it is giving low value and sometimes it is giving negative values.
to get zero here what i have to do.
I am using gain = 8 and odr = 52.66sps ,
back ground calculation = 2;
scan mode: single channel continuous conversion
And while I am reading same channel I am getting different values. for example I am applying 14.77mv for this I am getting 1. 03a9cd(hex)
2. 039F52(hex)
3. 0399DF(hex)
How to reduce this difference
Thanks & Regards
vijay kumar