Z-World RabbitLink EG2100, Руководство пользователя

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User’s Manual 27
C.4 Power Supplies
Power is supplied to the RabbitLink board from an external source either through jack J4 or
through screw terminal connector J5/J6. The connection through jack J4 is protected against
reverse polarity by a Sshottky diode at D1 as shown in Figure D-4, but the alternative connection
through J5/J6 is not protected against reverse polarity.
Figure D-4. RabbitLink Power Supply Schematic
The power supply connection through jack J4 is handy for the AC adapter included with the Rab-
bitLink tool kit for desktop demonstration and development. The power supply connection
through screw terminal connector J5/J6 enables you to connect the RabbitLink directly to a power
supply in the production system.
Capacitor C8 provides noise and ripple stablization protection for the voltage regulator, and allows
the external power supply to be located some distance away from the RabbitLink. A switching
power regulator is used. The +RAW or DCIN input voltage may range from 9 V to 40 V.
C.5 Batteries and External Battery Connections
Although the RabbitLink has room for a backup battery on the circuit board, battery backup is not
supported at this time.
C.6 Reset Generator
The RabbitLink uses a reset generator, U14, to reset the Rabbit 2000 microprocessor when the
voltage drops below the voltage necessary for reliable operation. The reset occurs between 4.50 V
and 4.75 V, typically 4.63 V.
47 µF
330 µF
LM2575
U16
Vcc
L1
C1
C8
330 µH
D2
1N5819
14
15
8
1
12
7
17
18
10
2
3
4
1
SWITCHING POWER REGULATOR
POWER
IN
J4
1
2
D1
+RAW
3
DCIN
J5/J6
6
1
J6
J5