Each ADC voltage channel is connected to the center pins of headers J1 through J16. The polarity of the channel pins are denoted by P and M above the respective channel header. Shunt jumpers can be placed on the headers to tie the P or M pins together, or short each to GND. 0402 footprints are provided to add a first-order, low-pass filter network on all ADC channels. By default, the filter capacitors are uninstalled and the filter resistors are populated with 0Ω. Use NP0 or C0G type capacitors and low-tolerance resistors to maintain AC performance when choosing to populate these footprints with a low-pass filter circuit.

Additionally, resistors (like R1) can be populated to short AINxP and AINxM. Other resistors (like R2) can be populated to short inputs to GND.

Figure 2-2 Input Channel