RabbitCore RCM3305, User Manual

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User’s Manual 85
B.3 Power Supply
The RCM3305/RCM3315 requires a regulated 3.15 V to 3.45 V DC power source to oper-
ate. Depending on the amount of current required by the application, different regulators
can be used to supply this voltage.
The Prototyping Board has an o5 V switching power regulator from which a
+3.3 V linear regulator draws its supply. Thus both +5 V and +3.3 V are available on the
Prototyping Board.
The Prototyping Board itself is protected against reverse polarity by a diode at D1 as
shown in Figure B-3.
Figure B-3. Prototyping Board Power Supply
LINEAR POWER
REGULATOR
POWER
IN
J4
10 µF
LM1117
U4
+3.3 V
3
1
2
1
2
3 DL4003
D1
47 µF
330 µF
+5 V
L1
C1
330 µH
D2
1N5819
SWITCHING POWER REGULATOR
DCIN
U1
LM2575
10 µF