The screw terminal block J1 is used to connect the external high voltage supplies. These supplies are not provided in the evaluation module kit and the expectation is that a low-noise lab supply is used to provide this power (for example, Keysight™ E3632A). The high-voltage supplies have transient voltage suppressor diodes to help protect the ADC from transients. These supplies are typically connected to ±15 V. For details on operation, see the ADS8555 data sheet. Figure 4-1 also shows how each supply has a light-emitting diode (LED) monitor for quick verification that power is applied.

Figure 4-1 External Power Connections and Test Points