SBAU488 June 2025 AMC23C15 , AMC3302
Figure 2-2 shows the analog input circuit for the AMC-AMP-200A-EVM.
The input is supplied through high current input lugs, connected to either end of R20. The input current is sensed through the bus-bar shunt resistor R20 and is carried into the analog inputs of the AMC3302 and into the analog input of the AMC23C15. The AMC3302 input is accessible to the user through test-points INP and INN. The AMC23C15 input is accessible to the user through test-points IN and REF.
For the AMC3302 input, the passive components R5, R8, and C14 make a differential anti-aliasing filter with a cutoff frequency of 497kHz. Ferrite beads FB1, FB2, and FB3 help to suppress high frequency signals on the signal lines. See the Best Practices to Attenuate AMC3302 Family Radiated Emissions EMI application note for more information. Capacitors C3, C4, C5, C12, and C13 serve as decoupling capacitors.
For the AMC23C15 input, the passive components R17 and C23 make an RC filter with a cutoff frequency of 1.59GHz. Passive components R18 and C24 define the adjustable threshold voltage determined by the desired overcurrent value. See the AMC23C15 data sheet for more details. Capacitors C19 and C20 serve as decoupling capacitors.