Xycom XVME 590, Manual

Page: 67 / 102

XVME-500/590 Manual
February, 1988
4.2.2
Programmable Gain Offset Adjustment
(version 2 & 3)
The following adjustments must be made for the input and output stage of the
programmable gain instrumentation amplifier:
1)
2)
Remove any connections at JKl
Set potentiometer R17 to center position. If the module is configured for
differential mode insert jumpers J23 and 24, if the module is in the
single-ended mode insert just jumper J23, and if the module is configured
for Pseudo-differential mode insert jumpers J23 and J17.
3)
4)
Set input to address the first channel (CH0).
Insert jumpers J15, and J19, and set the input stage gain to 1 (by setting
bits D6 and D7 of the Gain/Channel register to logic “0”). Measure and
record the amplifier output voltage
) at TP2 (TPl is ground).
5)
Set the input stage gain to 10 (by setting bits D6 and D7 of the
Gain/Channel register to logic “1”).
Measure and record the output
voltage (V, ) at TP2.
6) Calculate the voltage offset with the following formula:
Voltage Offset (Voos) =
[(10 *
9
7)
While maintaining an input stage gain of 10, adjust the input offset
voltage potentiometer (R17) until the output at TP2 is equal to Voos
8)
9)
Reset gain range jumpers to the desired range (see Table 2-6).
Remove grounding jumpers (J23 & J24).
4.2.3
Fixed Gain Offset Adjustment
(version 1)
The following adjustments must be made to the input and output stages of the fixed
gain instrumentation amplifier (version 1 only):
1)
Remove any connections at JKl
2)
If the module is configured for differential mode insert jumpers J23 and
24, if the module is in the single-ended mode insert just jumper J23, and
if the module is configured for Pseudo-differential mode insert jumpers
J23 and J17.
4-2