4-Port PoE Manager

Microsemi Proprietary and Confidential. PD69104B1/F Datasheet Revision 2.0

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Also, when total power > budget (above top line):

An internal digital power integration calculation machine starts integrating power

When this Integrated total power is larger than Budget + 12.5% (RED LINE) > lowest priority port

is turned OFF

This specific port LED is OFF

Max LED will reflect the NEW Total Power status

If ports turn off due to PM, their per port LEDs will blink (in PM frequency) and MAX_LED will

turn off

Timing to shut down this port is proportional to the over power (above budget) but limited to a

maximum of 2 seconds.

In 4 pairs mode, please use only the master LED per port (LED 1 and LED 3 are masters in 4 pairs

mode, LED 0 and 2 should not be used).

In 4 pairs mode, the port’s LED is blinking when the ports enters to UDL condition, unlike the 2 pairs

condition.

The following illustration shows the MAX_LED behavior description.

Figure 19 • MAX_LED Behavior Description

For example:

Budget = 100 W, GB = 20 W

When total power = 70 W – MAX LED is OFF

When total power = 85 W – MAX LED is ON (power Integrator is not activated)

When total power = 110 W – MAX LED BLINKS (power Integrator is activated)—Port at lowest

priority is shut off

Timing to shut off is based on : delta(P) x T = Power Budget × 1.125

off

In this example, 10 W x T = 100 W × 0.125 T = 1.25 seconds

off

off

If total power = 105 W delta (P) = 5, then T = 2 seconds (the max timer)

off

The following table lists the power budget for the PD69104B1/F device.