Electronic Components Datasheet Search
  English  ▼

Delete All
ON OFF
ALLDATASHEET.COM

X  

Preview PDF Download HTML

NCP1081 Datasheet(PDF) 4 Page - ON Semiconductor

Part No. NCP1081
Description  Integrated High Power PoE-PD Interface & DC-DC Converter Contr
Download  18 Pages
Scroll/Zoom Zoom In 100% Zoom Out
Maker  ONSEMI [ON Semiconductor]
Homepage  http://www.onsemi.com
Logo 

NCP1081 Datasheet(HTML) 4 Page - ON Semiconductor

 
Zoom Inzoom in Zoom Outzoom out
 4 / 18 page
background image
NCP1081
http://onsemi.com
4
SIMPLIFIED APPLICATION DIAGRAMS
Figure 4. Non−Isolated Fly−back with Extra Winding
Cpd
NCP1081
GATE
RTN
FB
VPORTN2
VDDH
VDDL
Rcs
Cvddh
C1comp
C2comp
Rcomp
Css
M1
R4
VPORTN1
CLASS
ARTN
ILIM1
INRUSH
TEST1
TEST2
Rclass
Rilim1
Rinrush
R1
R2
UVLO
CS
VPORTP
Rslope
D1
D2
T1
R5
Voutput
Spare
Pairs
RJ−45
DB1
DB2
LD1
Rd1
Cvddl
nCLASS_AT
R3
Cload
Rosc
Data
Pairs
Figure 4 shows the same non−isolated fly−back configuration as Figure 3, but adds a 12 V auxiliary bias winding on the
transformer to provide power to the NCP1081 DC−DC controller via its VDDH pin. This topology shuts off the current flowing
from VPORTP to VDDH and therefore reduces the internal power dissipation of the PD, resulting in higher overall power
efficiency.
Figure 5. Non−Isolated Forward Converter
Cpd
NCP1081
GATE
RTN
FB
VPORTN2
VDDH
VDDL
Rcs
Cvddh
C1comp
C2comp
Rcomp
Css
M1
Cload
R3
R4
VPORTN1
CLASS
ARTN
ILIM1
INRUSH
TEST1
TEST2
Rclass
Rilim1
Rinrush
R1
R2
UVLO
CS
VPORTP
L1
Rslope
Voutput
T1
D1
D2
D3
Spare
Pairs
RJ−45
DB1
DB2
LD1
Rd1
Cvddl
nCLASS_AT
Data
Pairs
Rosc
Figure 5 shows the NCP1081 used in a non−isolated forward topology.
High Power Considerations
The NCP1081 is designed to implement various
configurations of high−power PoE systems including those
based on the IEEE802.3at standard. High power operation
can be enabled by a Dual Event Layer 1 classification or a
Single Event Layer 1 classification combined with a Layer 2
high power classification. The NCP1081 also supports
proprietary designs capable of delivering 25 W to 40 W to
the load in two−pair configurations. A separate application
note describes these implementations (AND8332).


Html Pages

1  2  3  4  5  6  7  8  9  10  11  12  13  14  15  16  17  18 


Datasheet Download




Link URL




Privacy Policy
ALLDATASHEET.COM
Does ALLDATASHEET help your business so far?  [ DONATE ]  

About Alldatasheet   |   Advertisement   |   Datasheet Upload   |   Contact us   |   Privacy Policy   |   Alldatasheet API   |   Link Exchange   |   Manufacturer List
All Rights Reserved© Alldatasheet.com


Mirror Sites
English : Alldatasheet.com  |   English : Alldatasheet.net  |   Chinese : Alldatasheetcn.com  |   German : Alldatasheetde.com  |   Japanese : Alldatasheet.jp
Russian : Alldatasheetru.com  |   Korean : Alldatasheet.co.kr  |   Spanish : Alldatasheet.es  |   French : Alldatasheet.fr  |   Italian : Alldatasheetit.com
Portuguese : Alldatasheetpt.com  |   Polish : Alldatasheet.pl  |   Vietnamese : Alldatasheet.vn