PD64012

12-CHANNEL PoE MANAGER

Vp o rt

M e a s u rem en t

I

PoL

Se q u e n c e r

P o w e r M a n a ge m e nt

I

Cu r re n t a n d A C

Vo lta g e

M e asu re m e nt

Ch a n n e l RT

Co n tro l Sta tu s

O v e r lo a d /

D isco nn ec t

R eco v e ry

Co m

In te rface

SP I

Ov e rlo a d

Lo gic

DC Dis c o n n e c t

Lo gic

A C D isc on ne ct

Ma c ro

C la ssifica tio n

R e sis tor Line

D e tectio n

Re a l T im e

P rotectio n

8-b it

AD C

I

I

C u r re n t L im itin g

x12

Clo c k

O s c illa to r

VM A IN

Vm a in

48 + 5 v

Pu m p

Up

PO R

Vo lta g e

Re g u la to r

R ese t

+ 4 8 V

V P ORT P OS

VP O R TNE G

PO RT SE NS E

V p o r t L e v e l S h ifte r

L in e D e te c tio n

x1 2

A C D isc on ne ct G e ne ra to r

x1 2

AC D A C

8-b it

LD D A C

Vpo r t

10 -b it

AD C

Se n s e

Re s is to r

C las sificatio n

V m ain -1 7 V

Dig ita l

Dig ita l

An a lo g

An a lo g

MIS O

MO S I

SS

SC K

SC L

SD A

D C D isc on nec t

Co m p a ra to r

SP I

C o mmu n ic a tio n

I/O

Figure 5: Internal Block Diagram

Digital Section

Communication I/O

The PD64012 incorporates two communication interfaces. When operating in the Enhanced mode, an SPI bus

connects the PD63000 MCU to the PD64012s. The second interface is the I

the host).

Both interfaces are used to communicate the contents of internal registers between the PD64012 logic and the

MCU.

PoE Sequencer

This central block of the Digital section includes a combination of internal state machines (macros). It is fed from

the Overload/Disconnect Recovery circuit and from the Power Management block.

Power Management

Receives data from the Vport Measurement block and receives commands and controls from the Communication

Interface. This, in order to control the power allocated to the system, as defined by the host. Power Management

receives requests to enable ports and decides, by communicating with the Sequencer, whether power is to be

allocated.

Overload /Disconnect Recovery

There is a number of macros which decide on port enable and some on port disconnect.

Port enabling: Classification, Resistor Line Detection and Vport Measurement.

Port disable: AC Disconnect, DC Disconnect and Overload Logic. These macros are connected to the Channel RT

Control Status block. Based on the inputs from these macros, the Channel RT controller starts the shutdown

operation or the recovery process. This is done according to preprogrammed parameters for different time

windows, as shown in Figure 2, Power Limits.

www.powerdsine.com

© PowerDsine 2003

Information in this document subject

06-0003-058 (Rev. 2.8) / 5 August 2004

to change without prior notice.

9