Copyright © 2016

Microsemi

Page 19

Rev. 1.4, July 2017

CPG

– PoE BU

One Enterprise Aliso Viejo, CA 92656 USA

PD70211

PD Controller with Switching Regulator for

AF/AT/UPOE/HDBaseT/4-pair PoE Applications

Truth Table for Status of Flags

Number of Fingers “N”

(N-Event Classification)

SUPP_S1

SUPP_S2

AT_FLAG

HD_FLAG

4P_AT_FLAG

4P_HD_FLAG

1

X

X

Hi Z

Hi Z

Hi Z

Hi Z

2

H

L

0V

Hi Z

Hi Z

Hi Z

2

L

H

0V

Hi Z

Hi Z

Hi Z

2

H

H

0V

Hi Z

0V

Hi Z

3

L

H

0V

0V

Hi Z

Hi Z

3

H

L

0V

0V

Hi Z

3

H

H

0V

0V

0V

Hi Z

4

X

X

0V

0V

0V

Hi Z

5

RESERVED FOR FUTURE

6

X

X

0V

0V

0V

0V

Wall Adapter mode

PD70211 support wall adapter functionality, i.e. by setting WA_EN pin high it will give priority to the wall

adapter jack to supply the load.

WA_EN pin is used while connecting a wall-adapter voltage between VPP and VPN_OUT by means of an OR-

ing diode.

While WA_EN, Wall-adapter enable pin, is held low (referenced to VPN_IN), the front-end works as a normal

PD.

When WA_EN is raised high (referenced to VPN_IN) three internal operations are forced:

 The Isolation FET is turned OFF.

 All output flags AT_FLAG, HD_FLAG, 4P_AT_FLAG and 4P_HD_FLAG are activated (low state).

 Vaux output voltage is turned ON.

While activating WA_EN pin, the wall-adapter will supply input voltage for the DC-DC converter.

Having WA_EN at high state does not disable detection and classification modes.