For best performance, connect differential analog input signals through the SMA connectors on channels 1 and 2, as shown in Figure 3-1. Alternatively, headers are provided to directly connect inputs for dc measurements, or where best ac performance is not needed. A possibility is to use the fully-differential SMA inputs as single-ended inputs. Connect the single-ended input to either the AINP or AINN SMA connector, then use the supplied shunt to connect the unused input to GND via the header. The input driver circuits use the THS4551 fully-differential amplifier in a low pass, unity-gain configuration with an additional single-pole RC filter at the output. Multiple passive components around the amplifier are intentionally left uninstalled to give users the flexibility to customize the input drive circuit for specific application.

Figure 2-1 SMA Input Connections