Bridge questions
Posted: Thu Mar 28, 2019 1:38 pm
I'm considering DAC1500 or 1046 Bridge for measuring temperatures with RTDs. I'm a little confused with the guides.
https://www.phidgets.com/docs/1046_User ... idge_Input
1) I assume what is referred as bridge voltage (Vb) is the voltage that is on the 5V terminal. And this terminal is an output of the USB input voltage and the ADC reference. Is this true?
2) For computing range, if Vb=5V and Gain=1, I apply +2.5V to V-, the full scale range of voltages on V+ would be 0 to +5V correct? Note: I'm not sure this is possible without upsetting maximum input levels of ground+0.25V and 5V-0.25V.
3) For computing range, if Vb=5V and Gain=2, I apply +2.5V to V-, the full scale range of voltages on V+ would be +1.25 to +3.75V correct? Basically gain only applies to differential voltage between V+ & V- pins and not common mode voltage to ground.
4) Max bridge current spec is 50mA. I assume that means the current out of 5V connection.
All voltages relative to ground connection.
https://www.phidgets.com/docs/1046_User ... idge_Input
1) I assume what is referred as bridge voltage (Vb) is the voltage that is on the 5V terminal. And this terminal is an output of the USB input voltage and the ADC reference. Is this true?
2) For computing range, if Vb=5V and Gain=1, I apply +2.5V to V-, the full scale range of voltages on V+ would be 0 to +5V correct? Note: I'm not sure this is possible without upsetting maximum input levels of ground+0.25V and 5V-0.25V.
3) For computing range, if Vb=5V and Gain=2, I apply +2.5V to V-, the full scale range of voltages on V+ would be +1.25 to +3.75V correct? Basically gain only applies to differential voltage between V+ & V- pins and not common mode voltage to ground.
4) Max bridge current spec is 50mA. I assume that means the current out of 5V connection.
All voltages relative to ground connection.