Copyright © 2016

Microsemi

Page 25

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

Operation with an External DC Source

PD applications utilizing PD70211 IC may be operated with an external power source (DC wall adaptor). There

are two cases of providing power with an external source, the cases are presented in.

Figure 6 and Figure 7.

 External source connected to application’s low voltage supply rails. External source voltage level is

dependent on DCDC output characteristics. Described in

 Figure 6

 External source connected to PD device output connection toward the application (VPP to VPN

OUT).

External source voltage level is dependent on DCDC input requirements. Described in Figure 7

100nF

100V

Primary DC(+)

Bootstrap Winding

controller VCC

Primary DC (-)

Isolated Output

Isolated Output

Isolated DCDC

Application

SUPP_S1

SUPP_S2

-

SUPP_S2

IN1B

IN2B

OUTN

+

SUPP_S1

OUTP

IN1A

IN2A

Data- from

line XFMR

Data+ from

line XFMR

Spare+ from

line XFMR

Spare- from

line XFMR

TVS

(+) Input

(-) Input

D1

10K

10K

PD70211

Supp_S1

Rcls

VPNI

VPNI

Supp_S2

Rref

PGND

Figure 6: External Power Input connected to Application supply Rails

100nF

100V

Primary DC(+)

Bootstrap Winding

controller VCC

Primary DC (-)

Isolated Output

Isolated Output

Isolated DCDC

Application

SUPP_S1

SUPP_S2

-

SUPP_S2

IN1B

IN2B

OUTN

+

SUPP_S1

OUTP

IN1A

IN2A

Data- from

line XFMR

Data+ from

line XFMR

Spare+ from

line XFMR

Spare- from

line XFMR

R1

R4

R3

TVS

R2

(+) Input

(-) Input

D1

Q1

10K

10K

100nF

PD70211

Supp_S1

Rcls

VPNI

VPNI

Supp_S2

Rref

PGND