Atmel Xplained Pro Evaluation Kit ATSAMD20-XPRO ATSAMD20-XPRO Fiche De Données
Codes de produits
ATSAMD20-XPRO
609
Atmel | SMART SAM D20 [DATASHEET]
Atmel-42129K–SAM-D20_datasheet–06/2014
Notes:
1.
These values are only given as typical examples.
2.
Decoupling capacitor should be placed close to the device for each supply pin pair in the signal group, low
ESR caps should be used for better decoupling.
ESR caps should be used for better decoupling.
3.
An inductor should be added between the external power and the V
DD
for power filtering.
4.
Ferrite bead has better filtering performance than the common inductor at high frequencies. It can be added
between V
between V
DD
and V
DDANA
for preventing digital noise from entering the analog power domain. The bead
should provide enough impedance (e.g. 50
Ω at 20MHz and 220Ω at 100MHz) for separating the digital
power from the analog power domain. Make sure to select a ferrite bead designed for filtering applications
with a low DC resistance to avoid a large voltage drop across the ferrite bead.
with a low DC resistance to avoid a large voltage drop across the ferrite bead.
34.3
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
references. If the internal references are used instead, the following circuits in
and
are not
necessary.
Figure 34-2. External Analog Reference Schematic With Two References
V
DDCORE
1.6V to 1.8V
Decoupling/filtering capacitor 100nF
Decoupling/filtering capacitor 100nF
Core supply voltage / external decoupling pin
GND
Ground
GND
ANA
Ground for the analog power domain
Table 34-1. Power Supply
Connections, V
DDCORE
From Internal Regulator (Continued)
Signal Name
Recommended Pin Connection
Description
GND
AREFA
EXTERNAL
REFERENCE 1
4.7µF
100nF
GND
AREFB
EXTERNAL
REFERENCE 2
4.7µF
100nF
Close to device
(for every pin)