Datasheet

IEEE 802.3af/at-Compliant, Powered Device Interface

Controller with Integrated Power MOSFET

MAX5969D

8 ______________________________________________________________________________________

Pin Description (continued)

PIN NAME FUNCTION

9 WAD

Wall Power Adapter Detector Input. Wall adapter detection is enabled the moment V

- V

crosses

the mark event threshold. Detection occurs when the voltage from WAD to RTN is greater than 9V.

When a wall power adapter is present, the isolation n-channel power MOSFET turns off, 2EC current

sink turns on. Connect WAD directly to RTN when the wall power adapter or other auxiliary power

source is not used.

10 PG

Open-Drain Power-Good Indicator Output. PG sinks 230FA to disable the downstream DC-DC

converter while turning on the hot-swap MOSFET switch. PG current sink is disabled during detection,

classification, and in the steady-state power mode. The PG current sink is turned on to disable the

downstream DC-DC converter when the device is in sleep mode.

11 2EC

2-Event Classification Detect or Wall Adapter Detect Output. A 1.5mA current sink is enabled at 2EC

when a Type 2 PSE or a wall adapter is detected. When powered by a Type 2 PSE, the 2EC current

sink is enabled after the isolation MOSFET is fully on until V

drops below the UVLO threshold. 2EC is

latched when powered by a Type 2 PSE until V

drops below the reset threshold. 2EC also asserts

when a wall adapter supply, typically greater than 9V, is applied between WAD and RTN. 2EC is not

latched if asserted by WAD. The 2EC current sink is turned off when the device is in sleep mode.

12 CLS

Classification Resistor Input. Connect a resistor (R

CLS

) from CLS to V

to set the desired classification

current. See the classification current specifications in the Electrical Characteristics table to find the

resistor value for a particular PD classification.

–– EP

Exposed Pad. Do not use EP as an electrical connection to V

. EP is internally connected to V

through a resistive path and must be connected to V

externally. To optimize power dissipation,

solder the exposed pad to a large copper power plane.