Phase current sensing circuit with shunt and opamp filter

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PhysicsTest
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TL;DR
Phase current sensing and the phase delay
This is the phase current sensing circuit
Schematic of a differential shunt current sense amplifier using op-amp U5:B (MCP6024): inputs SHUNT_HIGH_SUM and SHUNT_HIGH_2 via 1K resistors R45 and R37, with C26 56pF across the inputs, 1K feedback resistors R46 and R38, 30K feedback resistor R52, 30K reference resistor R33 to VREF, output through 1K R55 to IMOTOR2 with C32 1nF to ground.


Here the phase currents are converted to voltages by passing through shunt resistor and fed to the opamp. Two questions i have
a. Can I analyze the R45, R37, C26 as one filter circuit and the remaining as other circuit for gain?
b. The phase currents are converted into voltages after passing through shunt resistor and are available at the output of the opamp. Does the capacitor C26 add any phase delay?
 
R45, R37, C26 has a product of about 100 ns, so it will only remove RF.

PhysicsTest said:
Does the capacitor C26 add any phase delay?
Not really. The TC is small compared to R55 * C32 = 1 us, which is probably an antialiasing filter before an A to D converter.

The gain of the shunt amplifier is set by series 1k + 1k = 2k input, to 30k output, gain = x15.