BeagleBoard XM C2, Справочное руководство

Страница: 95 / 163

REF: BB_SRM_xM
BeagleBoard-xM System
Reference Manual
Revision C2
Page 95 of 163
The current available on the DC_5V rail is limited to the available current that remains
from the DC supply that is connected to the DC power jack on the board. Keep in mind
that some of that power is needed by the USB Host power rail and if more power is
needed for the expansion board, the main DC power supply current capability may need
to be increased. All signals are 1.8V except the DVI_PUP which is a 3.3V signal.
Table 17 shows the signals that are on connector P13.
Table 17. P13 LCD Signals
Pin# Signal I/O Description
1 3.3V PWR 3.3V reference rail
2 VIO_1V8 PWR 1.8V buffer reference rail.
3 DVI_DATA20 O LCD Pixel Data bit
4 DVI_DATA21 O LCD Pixel Data bit
5 DVI_DATA17 O LCD Pixel Data bit
6 DVI_DATA18 O LCD Pixel Data bit
7 DVI_DATA15 O LCD Pixel Data bit
8 DVI_DATA16 O LCD Pixel Data bit
9 DVI_DATA7 O LCD Pixel Data bit
10 DVI_DATA13 O LCD Pixel Data bit
11 DVI_DATA8 O LCD Pixel Data bit
12 nUSB_PWR O
LO indicates power is
from the USB port. HI
indicates that power is
from the DC jack.
13 DVI_DATA9 LCD Pixel Data bit
14 I2C3_SCL I/O I2C3 Clock Line
15 DVI_DATA6 O LCD Pixel Data bit
16 O DVI Clock
17 DVI_DEN O Data Enable
18 DVI_HSYNC O Horizontal Sync
19 GND PWR Ground bus
20 GND PWR Ground bus
The 1.8V rail is for level translation only and should not be used to power circuitry on the
board. The 3.3V rail also has limited capacity on the power as well. If the
TFP410 is
disabled on the Beagle, then 80mA is freed up for use on an adapter card connected to the
LCD signals connectors. It is not required that the
TFP410 be disabled when running an
adapter card, but the power should be taken into consideration when making this
decision.
It is suggested that the 5V rail be used to generate the required voltages for an adapter
card.