Measurement Computing Data Translation DT3034 User Manual page 126

Calibrating the Analog Input Subsystem
This section describes how to configure the DT740 screw terminal panel for an internal or
external reference, and how to use the DT3034 Calibration Utility to calibrate the analog input
subsystem of the board.
Choosing a Calibration Reference
To calibrate the analog input circuitry, you can use either of the following references:
• The internal +5 V reference on the DT3034 board.
Using the +5 V reference on the board allows you to calibrate the analog input circuitry
quickly without using external equipment; the accuracy of the calibration is
approximately 0.05%.
• An external +9.3750 V reference (precision voltage source).
Using an external +9.3750 V reference provides an accuracy of approximately ±1 LSB.
This section describes how to configure for an internal or external reference.
Configuring for the Internal Reference
To calibrate the analog input circuitry using the internal +5 V reference, do the following:
1. Connect Analog In 0 to +5 V Reference Out.
2. Connect Analog In 0 Return to Analog Ground.
3. Connect Analog In 1 to Analog In 1 Return and Analog Ground.
Signal DT740 Screw Terminal
Analog Input 0
+5 V Reference
Signal
Analog Input 0 Return
Analog Ground
TB1
TB49
DT740 Screw Terminal
TB2
TB34
Calibration
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