42.4 External Analog Reference Connections

The following schematic checklist is only necessary if the application is using the external analog reference. If the internal reference is used instead, the following circuits are not necessary.

Figure 42-3. External Analog Reference Schematic
Table 42-2. External Analog Reference Connections
Signal NameRecommended Pin ConnectionDescription
VREFA2.4V to AVDD - 0.6V for ADC (2)

Decoupling/filtering capacitors: 100nF(1,2,3) and 4.7µF(1)

External reference from VREFA pin on the analog port.
GNDGround
Note:
  1. Refer to Power Supply Electrical Specifications from the Electrical Characteristics chapter.
  2. Refer to the Electrical Characteristics chapter for the intended peripheral to be used with VREFA to determine suggested operational conditions. These peripherals include the ADC and AC.
  3. Decoupling capacitor must be placed close to the device for each supply pin pair in the signal group.