Part II: PCM-959/phyCORE-OMAP44xx Carrier Board
phyCORE-OMAP44xx
100
©
PHYTEC Messtechnik GmbH
2012
L-760e_1
2.1.3.2.2 Power over Ethernet (PoE)
The Power-over-Ethernet (PoE) circuit provides a method of powering the board via the Ethernet interface.
In this configuration the phyCORE-OMAP44xx Carrier Board acts as the Powered Device (PD) while the connect-
ing Ethernet interface acts as the Power Source Equipment (PSE). For applications that require Ethernet
connectivity this is an extremely convenient method to also simultaneously provide power. To make use of the
PoE circuit you must have a PSE for connectivity. Typically a PoE enabled router or switch can be used.
LED D18 indicates the availability of the PoE supply voltage.
The PoE circuit generates a supply voltage of 12 V, which is feed into the VCC_12_24 branch through a diode.
The IEEE PoE standard restricts the maximum amount of power a PSE must provide and therefore a PD can
consume. The phyCORE-OMAP44xx PoE circuit was designed to provide up to 25 W of power to the board.
The phyCORE-OMAP44xx Carrier Board Ethernet connector X9 supports both PSE power sourcing methods of
power over the data wires, or power over the spare wires.
Note:
For powering up the phyCORE the following actions have to be done:
1. Plug in the power supply connector
» The power LEDs D14 - D17 should light up and the phyCORE sends serial data from UART3 to the top
DB-9 sub-connector of connector P1.
2. For powering down the phyCORE-OMAP44xx button S3 should be pressed for a minimum time of 10 s.
3. To restart the system press button S3 for approx. 2 s.
» All power LEDs should light up again and the phyCORE sends serial data from UART3 to the top DB-9
sub-connector of connector P1.
Caution:
The PoE circuit was designed to provide up to 25 W of power to the board. This is less than the board can
potentially consume. Be aware that this limitation could cause board operation to fail if peak power is
exceeded due to enabled peripherals. Do not supply the system over Ethernet, if the power consumption
expected is more than 25 W ! Do not change modules or jumper settings while the carrier board is supplied
with power over the Ethernet!
Note:
For powering up the phyCORE the following actions have to be done:
1. Plug in the POE supply connector
» The power LEDs D14 - D18 should light up and the phyCORE sends serial data from UART3 to the top
DB-9 sub-connector of connector P1.
2. For powering down the phyCORE-OMAP44xx button S3 should be pressed for a minimum time of 2000 ms.
3. To restart the system press button S3 for a maximum time of 1000 ms.
» All power LEDs should light up again and the phyCORE sends serial data from UART3 to the top DB-9
sub-connector of connector P1.
