The analog inputs to the printed-circuit board (PCB) consists of an RC filter circuit and ferrite beads. By default, R2 and R4 on the analog input are populated as 10-Ω resistors. Capacitor C12 is populated with a 10-nF capacitor. This antialiasing filter has a cutoff frequency of 796 kHz, which is within the recommended cutoff frequency range of 200 kHz and 2 MHz. Figure 2-1 shows an example input circuit for the AMC3301, AMC3302, and AMC3330 devices.
By using a signal generator or other voltage source, the user can apply an input signal directly to J2.1. The linear input voltage range of the AMC3301 is –250 mVDC to 250 mVDC, whereas the linear input voltage range of the AMC3302 is –50 mVDC to 50 mVDC, and the range of the AMC3330 is –1 VDC to 1 VDC referenced to J3.3, GND1. If measuring across an external shunt resistor, tie J2.1 to the positive Kelvin connection terminal and J2.2 and J2.3 to the negative Kelvin connection terminal of the shunt resistor.