Part Number: INA125
For the last six months, I have been using INA 125 P amplifier. The problem I am facing is that in figure 6, page number 13 in the datasheet, pins 14 and 4 have been connected and due to this connection, we would be getting a reference voltage of 2.5V (as is shown in the figure). Experimentally, I also made the same connection but I am getting a reference voltage of 1.44V. Why this anomaly is happening when everything is correct in my circuit? Please help.
Zak Kaye Precision Amplifiers Applications
In reply to Zak Kaye:
I am attaching the schematic herewith
I have exactly made these connections. But my problem is that in the highlighted regions, I am getting a voltage of 1.44V instead of 2.5 volt. Pins 12,3 have been connected to the ground of the Wheatstone bridge. And at pin 1, I am supplying a voltage of 5V as is given in the data sheet. Pin 2 has been connected to pin 1.
My problem is that I want to get 2.5 V as the voltage which excites the Wheatstone bridge.
In reply to CAPTAIN SWING:
The effective resistance (or equivalent resistance) of my bridge is 109.091 ohm. And if I disconnect the bridge, I do get the expected 2.5 volt.
I am attaching herewith the diagram
So, what should be the net resistance of my bridge so that I can get the expected 2.5 Volts or any other reference voltage as given in the datasheet.
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