This design looks good on paper and on the bench, as long as I don't load the FETs, that is connect the drains. When I get this all tuned and balanced, I get a scope picture like this,
This is TP 9 & 10. TP2 should be a smooth line at 5.00 vdc and it is, but when I connected a resistive load to the Power FET driven by OP7, I got this on the scope, Yellow trace, Green trace is the saw tooth I use to create my pulse width output.(no torque on steering wheel)(and only one FET connected)
When I apply enough torque to the steering wheel to get the Pulse width to 100%, TP2 goes flat and smoother again.
My apologies if this is double posting, but I still have a problem. I'm planning on changing the Wheatstone bridge amp when I get the IC, Maybe that will fix every thing.
Does anyone have any suggestions on understand why TP2 distorts,
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