The way I see it there are two issues so far:
1) I do not know the precise pinout of my sensor.
2) There may be something wrong with my amplification stage.
I rewired the Sensor, energizing 5V across pins 2 and 5. The response as I swing from 0 - 15 PSI and back down to 0 PSI is attached. I am measuring between pin 4 (+OUT) and pin 6 (-OUT). (Measuring across pin 3 and 6 does nothing!) These correspond to the MPS20N0040D-D data sheet, except for pin3 which on my sensor is actually pin 4. I see roughly 40 mV change for 15 PSI difference. My voltage baseline for 0 PSI is ~ 1.98V
After hooking +OUT of the sensor (pin 4) to +IN of my OPA (pin 3) and -OUT of sensor (pin 6) to -IN of my OPA I am still getting no amplification. I am reading a base voltage of ~4.3 - 4.5 V
I have attached a new schematic. Should I just play around with my Rg now or is there something else I am doing fundamentally wrong in the amplification stage?
Thanks for everyone's help so far.
1) I do not know the precise pinout of my sensor.
2) There may be something wrong with my amplification stage.
I rewired the Sensor, energizing 5V across pins 2 and 5. The response as I swing from 0 - 15 PSI and back down to 0 PSI is attached. I am measuring between pin 4 (+OUT) and pin 6 (-OUT). (Measuring across pin 3 and 6 does nothing!) These correspond to the MPS20N0040D-D data sheet, except for pin3 which on my sensor is actually pin 4. I see roughly 40 mV change for 15 PSI difference. My voltage baseline for 0 PSI is ~ 1.98V
After hooking +OUT of the sensor (pin 4) to +IN of my OPA (pin 3) and -OUT of sensor (pin 6) to -IN of my OPA I am still getting no amplification. I am reading a base voltage of ~4.3 - 4.5 V
I have attached a new schematic. Should I just play around with my Rg now or is there something else I am doing fundamentally wrong in the amplification stage?
Thanks for everyone's help so far.
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