I'm studying reference design from TI (pdf).This design shows the solenoid control circuit. I was interested, why a differential amplifier is used to measure the current? Why not use non-inverting circuit op-amp?
A differential input with Kelvin connection from shunt to amplifier will reject noise much more effectively than a single-ended input. I think this is the main reason. If it were single ended, some common mode noise might couple onto the trace. With differential pair routing, noise will most likely couple onto both traces equally and be rejected by the amplifier.