Figure 48-4. External Analog Reference Schematic With Two References
GND
VREFA
EXTERNAL
REFERENCE 1
4.7μF
100nF
GND
VREFB
EXTERNAL
REFERENCE 2
4.7μF
100nF
Close to device
(for every pin)
Figure 48-5. External Analog Reference Schematic With One Reference
GND
VREFA
EXTERNAL
REFERENCE
4.7μF
100nF
GND
VREFB
100nF
Close to device
(for every pin)
Table 48-2. External Analog Reference Connections
Signal Name Recommended Pin Connection
Description
V
REFA
/V
REFB
1.0V to (V
DDANA
- 0.6V) for ADC
Decoupling capacitors
100nF
(1)(2)
and 4.7µF
(1)
External reference V
REFA
/V
REFB
for the analog port
GND
Ground
1. These values are only given as a typical example.
2. Decoupling capacitor should be placed close to the device for each supply pin pair in the signal group.
Atmel SAM L22G / L22J / L22N [DATASHEET]
Atmel-42402E-SAM L22G / L22J / L22N_Datasheet_Complete-07/2016
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