MAX5940A/MAX5940B/MAX5940C/MAX5940D
IEEE 802.3af PD Interface Controller
For Power-Over-Ethernet
______________________________________________________________________________________ 13
60V
68nF
UVLO
GND
V
EE
GATE
RCLASS
PGOOD
PGOOD
DC-DC CONVERTER
GND
-48V
WALL
ADAPTER
SUPPLY
R
CL
D1
GND
V+
VREG
OUT
1
2
3
4
5
6
7
8
C
OUT
C
GATE
R
DISC
25.5kΩ
SS_SHDN
MAX5014
MAX5940B
MAX5940D
LOAD
Typical Application Circuits (continued)
Application Circuit 4
If the wall adapter supply comes up first, it provides
power to the load and pollute the discovery and classi-
fication signatures. If the power-over-ethernet comes
up first, it powers the load until taken over by a wall
adapter with higher output voltage.
Figure 7. Adding Wall Adapter Input Supply (the One with Higher Voltage Provides Power to the Load)
MAX5940A/MAX5940B/MAX5940C/MAX5940D
IEEE 802.3af PD Interface Controller
For Power-Over-Ethernet
14 ______________________________________________________________________________________
PGOOD
OUTV
EE
1
2
8
7
GND
N.C.RCLASS
GATE
N.C.
SO
TOP VIEW
3
4
6
5
MAX5940A
MAX5940C
PGOOD
OUTV
EE
1
2
8
7
GND
PGOODRCLASS
GATE
UVLO
SO
3
4
6
5
MAX5940B
MAX5940D
Pin Configurations
R1**
60V
68nF
UVLO
GND
V
EE
GATE
RCLASS
PGOOD
PGOOD
DC-DC CONVERTER
GND
-48V
R2**
R
CL
*OPTIONAL.
**R1 AND R2 ARE OPTIONAL AND WHEN USED, THEY MUST TOTAL 25.5kΩ AND REPLACE THE 25.5kΩ RESISTOR.
V
REG
OUT
1
2
3
4
5
6
7
8
C
OUT
C
GATE
R
DISC
25.5kΩ
MAX5940B
MAX5940D
D1*
D2*
GND
V+
SS_SHDN
MAX5014
LOAD
Typical Operating Circuits (continued)
Chip Information
TRANSISTOR COUNT: 3,643
PROCESS: BiCMOS
MAX5940A/MAX5940B/MAX5940C/MAX5940D
IEEE 802.3af PD Interface Controller
For Power-Over-Ethernet
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are
implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.
Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________ 15
© 2006 Maxim Integrated Products is a registered trademark of Maxim Integrated Products, Inc.
Package Information
(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information,
go to www.maxim-ic.com/packages
.)
SOICN .EPS
PACKAGE OUTLINE, .150" SOIC
1
1
21-0041
B
REV.DOCUMENT CONTROL NO.APPROVAL
PROPRIETARY INFORMATION
TITLE:
TOP VIEW
FRONT VIEW
MAX
0.010
0.069
0.019
0.157
0.010
INCHES
0.150
0.007
E
C
DIM
0.014
0.004
B
A1
MIN
0.053A
0.19
3.80 4.00
0.25
MILLIMETERS
0.10
0.35
1.35
MIN
0.49
0.25
MAX
1.75
0.050
0.016L
0.40 1.27
0.3940.386D
D
MINDIM
D
INCHES
MAX
9.80 10.00
MILLIMETERS
MIN
MAX
16
AC
0.337 0.344 AB8.758.55 14
0.189 0.197 AA5.004.80 8
N MS012
N
SIDE VIEW
H 0.2440.228 5.80 6.20
e 0.050 BSC 1.27 BSC
C
HE
e
B
A1
A
D
0-8
L
1
VARIATIONS:

MAX5940DESA+T

Mfr. #:
Manufacturer:
Maxim Integrated
Description:
I/O Controller Interface IC IEEE 802.3af PD Int Controller
Lifecycle:
New from this manufacturer.
Delivery:
DHL FedEx Ups TNT EMS
Payment:
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