Application background:
We are using MC9S12ZVMC25F1WKK intending to drive a motor (SRM) by its on-chip GDU module. The figure as shown is Current Sense Amplifier circuits configured with the datasheet.
Description:
In addition, No matter Normal or Abnormal, it has been confirmed that the positive input voltage of the amplifier is 33 mV and Voffset is 0 .
Questions:
Hi,
Please replace the 200 ohm resistor with 1K. WHy?
1) Gain = 30k/200 = 150 is probably out of specification of the amplifier
2) Since Rp = Rn, then Rp/a = Rn/a. Your opamp configuration is unbalanced, therefore, I'm pretty sure it will not work.
Best regards
Matej