MrDEB
Well-Known Member
using a 18F4520 and an RTD sensor. I want an increase in the ADC readings to indicate the status of the RTD sensor.
Using an RTD amplifier circuit but the results are dismal
The voltages at VF4 change according but can't get the same on the ADC readout.
Doing something wrong or need to change something.
The code is in Swordfish and using
So the reference voltage is right
op amp 1 is a constant current source. That section seems to be working fine.
all I am after is better resolution on the LCD display. Presently it indicates .0081 regardless if the RTD is 50 ohms or 100 ohms.
Using an RTD amplifier circuit but the results are dismal
The voltages at VF4 change according but can't get the same on the ADC readout.
Doing something wrong or need to change something.
The code is in Swordfish and using
Code:
Function sensor() As Word
result = (ADC.Read(0)+1)*500/1024 //14 (RT) to 37 (melt) *30+22
End Function
op amp 1 is a constant current source. That section seems to be working fine.
all I am after is better resolution on the LCD display. Presently it indicates .0081 regardless if the RTD is 50 ohms or 100 ohms.