17.3 External Analog Reference Connections

The following schematic checklist is only necessary if the application is using one or more of the external analog references. If the internal references are used instead, the following circuits in Figure 17-3 and Figure 17-4 are not necessary.

Figure 17-3. External Analog Reference Schematic With Two References

Figure 17-4. External Analog Reference Schematic With One Reference

Table 17-2. External Analog Reference Connections
Signal Name	Recommended Pin Connection	Description
VREFx	1.0V to (V_DDANA – 0.6V) for ADC  Decoupling/filtering capacitors 100 nF⁽¹⁾⁽²⁾ and 4.7µF⁽¹⁾	External reference VREFx for the analog port
GND	—	Ground

Note:

These values are only given as a typical example.
It is recommended that the decoupling capacitor be placed close to the device for each supply pin pair in the signal group.