OMAP
TM
4 PandaBoard System
Reference Manual
Revision 0.4
September 22, 2010
DOC-21010
Page 24 of 83
Figure 3 – SYSBOOT[5:0] Resistor Locations
2.7
Miscellaneous Power Circuitry
2.7.1
Input Power Circuitry
The input power circuitry may be found on sheet 2 of the board schematic. A block diagram of this
circuitry is shown in Figure 4 below. The PandaBoard may be run either with or without a DC wall
supply plugged into the input power jack at P3.
Without an external power supply plugged in, the 5Vdc input power is supplied from the mini-AB
USBOTG connector at J18. This supply is only capable of providing 500mA of output current, so board
operations will be limited in this mode (e.g. USB host port operation will not be possible, and other
operations could be limited, depending on current requirements). The path of current flow in this mode is
designated below by the red arrow. The 5V from VBUS will be routed through the switch at U22, to the
LDO at U23, which provides a 4.2V “battery” voltage for the TWL6030 and TWL6040 Companion ICs.
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