OMAP4460 Pandaboard ES
System Reference Manual
Revision 0.1
September 29, 2011
DOC-21054
Page 47 of 82
2.20
LED Indicators
The Pandaboard ES provides three LED indicators. See Figure 18 for the location of these three LEDs on
the Panda PCB.
LEDs D1 and D2 are green LEDs. D1 is controlled via OMAP4460 GPIO_110 (ball AD27), while D2 is
controlled via OMAP4460 GPIO_WK8 (ball AC3). For both of these LEDs, writing the GPIO high will
turn on the LED, while writing it low will turn off the LED.
LED D3 is a red LED that is controlled automatically via onboard circuitry. This LED being illuminated
indicates an overvoltage condition on the input DC supply (i.e. a supply of greater than 5V has been
plugged into P3). The supervisor IC at U19 on sheet 2 of the schematics monitors the voltage from the
DC input jack (through a voltage divider to set the appropriate threshold). If a DC supply of more than
5V is plugged into the Pandaboard ES, the U19 output reset will be negated, which will turn on the red
LED at D3 and disable load switch U16 on sheet 2 of the schematic, which will remove 5V power to the
remainder of the Pandaboard ES circuitry. This is intended to prevent damage to onboard circuitry.
Figure 18 – Pandaboard ES LED Locations
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