Hey folks,
Am a novice at electronics and new to this forum , so please try and correct my limitations .
I have been working on a load cell circuit for a project of mine. However i am unable to go past the amplifying stage of the circuit . I am using the INA 125 burr brown amplifier whose datasheet can be found here : http://www.ti.com/lit/ds/symlink/ina125.pdf .
Following the instructions in the datasheet i have made the following connection as shown in the jpg file .
What i see in the datasheet is that the amplification is based on a single resistor Rg that is to be connected across pin 8 and pin 9 of the INA 125 IC .
However given a certain input voltage , the amplified output that is read across pin 11 and ground doesn't seem to go beyond the applied reference voltage even if mathematically according to the value of Rg it is supposed to .
For eg : The INA 125 is connected across 12V and when the input between pins 6 and 7 is 0.03V and the applied resistor is 6 ohms , the desired amplification is 10000 i.e the output across pin 11 and ground is supposed to be 30V but the voltage reads 11.3 V . The output just doesn't exceed 12V ( Vref) for any combination of inputs and resistors.
Hopefully I have been clear regarding my doubt . Thank you in advance .
P.S : Please forgive the bad image of the circuit diagram .
Am a novice at electronics and new to this forum , so please try and correct my limitations .
I have been working on a load cell circuit for a project of mine. However i am unable to go past the amplifying stage of the circuit . I am using the INA 125 burr brown amplifier whose datasheet can be found here : http://www.ti.com/lit/ds/symlink/ina125.pdf .
Following the instructions in the datasheet i have made the following connection as shown in the jpg file .
What i see in the datasheet is that the amplification is based on a single resistor Rg that is to be connected across pin 8 and pin 9 of the INA 125 IC .
However given a certain input voltage , the amplified output that is read across pin 11 and ground doesn't seem to go beyond the applied reference voltage even if mathematically according to the value of Rg it is supposed to .
For eg : The INA 125 is connected across 12V and when the input between pins 6 and 7 is 0.03V and the applied resistor is 6 ohms , the desired amplification is 10000 i.e the output across pin 11 and ground is supposed to be 30V but the voltage reads 11.3 V . The output just doesn't exceed 12V ( Vref) for any combination of inputs and resistors.
Hopefully I have been clear regarding my doubt . Thank you in advance .
P.S : Please forgive the bad image of the circuit diagram .
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