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Hardware Description
3-46
Copyright © ARM Limited 2000. All rights reserved.
Power input to the P1100 is selected automatically. If an external supply is inserted and
switched on, it causes a MOSFET switch arrangement (U38) to select the reg3V
source in preference to the +3V battery supply.
3.15.2
Power supply inputs
The P1100 can be powered from two sources:
•
external power supply
•
battery
The choice of power source largely depends on the type of system you have.
External power supply
An external power supply can be connected to the 1.3mm jack JP32 (see Supplying
power on page 2-4). The external supply should provide an output voltage of between
+6V and +12V. If a backlit display is being used, then a 9V/1.5A supply is needed.
A suitable power supply is shipped with the P1100 system.
Two linear regulators p3V and +5V to the system:
3V regulator Linear Technology LT1085, positive adjustable linear regulator, able to
supply an output current of 3A. Fitted with a 10.4 C/W heatsink.
5V regulator National Semiconductor LM2940CT-5.0 is a fixed 5V linear regulator,
capable of providing 1A.
The +5V supply is used for system expansion only and the +3V supply is used directly
for FPGA expansion in high current drain applications.
Battery power
A battery connector (JP33) allows the use of 2xAA batteries sup3V. An
automatic switch is used to select one input supply or the other, with the external supply
taking precedence. The common (selected) supply signal name is
3V_SUPPLY
.
Systems that are fitted with a display provide a battery compartment located beneath the
display hinge (see Installing batteries on page 2-4). This can accommodate two AA
sized batteries. You can also wire your own battery holder to JP33.
Caution
Take great care to connect the battery with the correct polarity. The positive pin (JP33
pin 2) is closest to the edge of the board.
Содержание Prospector P1100
Страница 1: ...ARM DUI 0122A Prospector P1100 User Guide ...
Страница 4: ...iv Copyright ARM Limited 2000 All rights reserved ARM DUI 0122A ...
Страница 86: ...Hardware Description 3 54 Copyright ARM Limited 2000 All rights reserved ARM DUI 0122A ...
Страница 140: ...Connector reference A 18 Copyright ARM Limited 2000 All rights reserved ARM DUI 0122A ...