Part Number: INA240
Previous thread last two Tina models, indicate linear output with REF=GND. However the real output is not as linear and crosses 0V >-21mV. Also the idle Real 3 output/s got real quiet <6mV noise, very impressive. Oddly REF=GND is not controlling Real differential amp/s linear region as Tina Spice model indicates it does very well. Point being how can we trust the Real Spice results when 240 is no where close to producing a linear output? Asked last thread what would be a better circuit configuration to produce better linear region as plots indicate for (-IN=510k)?
Scope capture of Real linear results differs greatly from Spice projection! Yet output signal has the full ± (expected) signature not being produced from -IN tied directly to ground. Oddly making only center and last sensors Real lowered the digital output to more closely match an external current monitor. When 3 sensors were modified (-IN=510k) the digital results were way off from the external current monitors readout and 240 system could not detect rotor loading other than by PWM drive.
This capture is the Real results, note a full shunt ± (current) signature is very much present but not so linear as Spice had predicted.
