The analog input of the EVM is accessible to the user by connector J3. The passive components of the analog input section are comprised of R1, R3, and C8 that form a simple differential antialiasing filter with a corner frequency of 796 kHz. The input of the AMC1411 is single-ended; therefore, R3 is not installed. R1 and C8 on the AMC1411EVM form a simple antialiasing filter with a corner frequency of 1.6 MHz. An antialiasing cutoff frequency between 200 kHz and 2 MHz is recommended. By default, INN (pin 3) of the AMC1400 and SHTDN (pin 3) of the AMC1411 is tied to GND1 (pin 4) by a 0 Ω resistor (R5). Figure 2-1 shows the input circuit for the AMC1400EVM.

Using a signal generator or other voltage source, the user can apply an input signal directly to J3.1. The linear input voltage range of the AMC1400 by J3.1 is –250 mVDC to 250 mVDC, whereas the linear input voltage range of the AMC1411 is 0 VDC to 2 VDC referenced to J3.3, GND1. If measuring across an external shunt resistor, tie J3.1 to the positive Kelvin connection terminal and tie J3.3 to the negative Kelvin connection terminal of the shunt resistor.