EVALUATION KIT AVAILABLE
MAX5969A/MAX5969B
IEEE 802.3af/at-Compliant, Powered Device Interface
Controllers with
Integrated Power MOSFET
General Description
The MAX5969A/MAX5969B provide a complete interface
for a powered device (PD) to comply with the IEEE®
802.3af/at standard in a power-over-Ethernet (PoE)
system. The MAX5969A/MAX5969B provide the PD
with a detection signature, classification signature,
and an integrated isolation power switch with inrush
current control. During the inrush period, the MAX5969A/
MAX5969B limit the current to less than 180mA before
switching to the higher current limit (720mA to 880mA)
when the isolation power MOSFET is fully enhanced. The
devices feature an input UVLO with wide hysteresis and
long deglitch time to compensate for twisted-pair cable
resistive drop and to assure glitch-free transition during
power-on/-off conditions. The MAX5969A/MAX5969B
can withstand up to 100V at the input.
The MAX5969A/MAX5969B support a 2-event classifica-
tion method as specified in the IEEE 802.3at standard
and provide a signal to indicate when probed by Type 2
power-sourcing equipment (PSE). The devices detect the
presence of a wall adapter power-source connection and
allow a smooth switchover from the PoE power source to
the wall power adapter.
The MAX5969A/MAX5969B also provide a power-
good (PG) signal, two-step current limit and foldback,
overtemperature protection, and di/dt limit.
The MAX5969A/MAX5969B are available in a space-
saving, 10-pin, 3mm x 3mm, TDFN power package. These
devices are rated over the -40NC to +85NC extended
temperature range.
S
S
S
S
S
S
S
S
S
S
S
S
Features
IEEE 802.3af/at Compliant
2-Event Classification
Simplified Wall Adapter Interface
PoE Classification 0 to 5
100V Input Absolute Maximum Rating
Inrush Current Limit of 180mA Maximum
Current Limit During Normal Operation Between
720mA and 880mA
Current Limit and Foldback
Legacy UVLO at 36V (MAX5969A)
IEEE 802.3af/at-Compliant, 40V UVLO (MAX5969B)
Overtemperature Protection
Thermally Enhanced, 3mm x 3mm, 10-Pin TDFN
Ordering Information
PART
MAX5969AETB+
MAX5969BETB+
PIN-
TEMP RANGE
PACKAGE
-40NC to +85NC 10 TDFN-EP*
-40NC to +85NC 10 TDFN-EP*
UVLO
THRESHOLD
(V)
35.4
38.6
+Denotes
a lead(Pb)-free/RoHS-compliant package.
*EP
= Exposed pad.
Pin Configuration
TOP VIEW
Applications
IEEE 802.3af/at Powered Devices
IP Phones, Wireless Access Nodes, IP Security
Cameras
WiMAX® Base Station
V
DD
DET
N.C.
I.C.
V
SS
1
2
3
4
5
+
10
9
CLS
2EC
PG
WAD
RTN
MAX5969A
MAX5969B
EP*
8
7
6
TDFN
(3mm × 3mm)
IEEE is a registered service mark of the Institute of Electrical
and Electronics Engineers, Inc.
WiMAX is a registered certification mark and registered
service mark of the WiMAX Forum.
*EP = EXPOSED PAD. CONNECT TO V
SS
.
For pricing, delivery, and ordering information, please contact Maxim Direct
at 1-888-629-4642, or visit Maxim’s website at www.maximintegrated.com.
19-5008; Rev 1; 7/15
MAX5969A/MAX5969B
IEEE 802.3af/at-Compliant, Powered Device Interface
Controllers with
Integrated Power MOSFET
ABSOLUTE MAXIMUM RATINGS
V
DD
to V
SS
..........................................................-0.3V to +100V
DET, RTN, WAD, PG,
2EC
to V
SS
....................... -0.3V to +100V
CLS to V
SS
..............................................................-0.3V to +6V
Maximum Current on CLS (100ms maximum) .................100mA
Continuous Power Dissipation (T
A
= +70NC) (Note 1)
10-Pin TDFN (derate 24.4mW/NC above +70NC)
Multilayer Board ........................................................1951mW
Operating Temperature Range .......................... -40NC to +85NC
Maximum Junction Temperature.....................................+150NC
Storage Temperature Range............................ -65NC to +150NC
Soldering Temperature (reflow) .................................... +260NC
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute
maximum rating conditions for extended periods may affect device reliability.
PACKAGE THERMAL CHARACTERISTICS (Note 2)
Junction-to-Ambient Thermal Resistance (θ
JA
) .................. 4NC/W
Junction-to-Case Thermal Resistance (θ
JC
) ....................... 9NC/W
Note 1:
Maximum power dissipation is obtained using JEDEC JESD51-5 and JESD51-7 specifications.
Note 2:
Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a four-
layer board. For detailed information on package thermal considerations, refer to
www.maximintegrated.com/thermal-
tutorial.
ELECTRICAL CHARACTERISTICS
(V
IN
= (V
DD
- V
SS
) = 48V, R
DET
= 24.9kω, R
CLS
= 619ω. RTN, WAD, PG, and
2EC
unconnected, all voltages are referenced to V
SS,
unless otherwise noted. T
A
= T
J
= -40
N
C to +85
N
C, unless otherwise noted. Typical values are at T
A
= +25
N
C.) (Note 3)
PARAMETER
DETECTION MODE
Input Offset Current
Effective Differential Input
Resistance
CLASSIFICATION MODE
Classification Disable
Threshold
Classification Stability Time
Class 0, R
CLS
= 619I
V
IN
= 12.5V to
20.5V, V
DD
=
RTN = WAD =
PG =
2EC
Class 1, R
CLS
= 117I
Class 2, R
CLS
= 66.5I
Class 3, R
CLS
= 43.7I
Class 4, R
CLS
= 30.9I
Class 5, R
CLS
= 21.3I
TYPE 2 (802.3at) CLASSIFICATION MODE
Mark Event Threshold
Hysteresis on Mark Event
Threshold
Mark Event Current
I
MARK
V
IN
falling to enter mark event, 5.2V
P
V
IN
P
10.1V
0.25
V
THM
V
IN
falling
10.1
10.7
0.84
0.85
11.6
V
V
mA
0
9.12
17.2
26.3
36.4
52.7
V
TH,CLS
V
IN
rising (Note 6)
22.0
22.8
0.2
3.96
11.88
19.8
29.7
43.6
63.3
mA
23.6
V
ms
I
OFFSET
dR
V
IN
= 1.4V to 10.1V (Note 4)
V
IN
= 1.4V up to 10.1V with 1V step,
V
DD
= RTN = WAD = PG =
2EC
(Note 5)
23.95
25.00
10
25.5
FA
kI
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
Classification Current
I
CLASS
2
Maxim Integrated
MAX5969A/MAX5969B
IEEE 802.3af/at-Compliant, Powered Device Interface
Controllers with
Integrated Power MOSFET
ELECTRICAL CHARACTERISTICS (continued)
(V
IN
= (V
DD
- V
SS
) = 48V, R
DET
= 24.9kω, R
CLS
= 619ω. RTN, WAD, PG, and
2EC
unconnected, all voltages are referenced to V
SS,
unless otherwise noted. T
A
= T
J
= -40
N
C to +85
N
C, unless otherwise noted. Typical values are at T
A
= +25
N
C.) (Note 3)
PARAMETER
Reset Event Threshold
POWER MODE
V
IN
Supply Voltage Range
V
IN
Supply Current
V
IN
Turn-On Voltage
V
IN
Turn-Off Voltage
V
IN
Turn-On/-Off Hysteresis
(Note 7)
V
IN
Deglitch Time
Inrush to Operating Mode
Delay
Isolation Power MOSFET
On-Resistance
RTN Leakage Current
CURRENT LIMIT
Inrush Current Limit
Current Limit During Normal
Operation
Foldback Threshold
LOGIC
WAD Detection Threshold
WAD Detection Threshold
Hysteresis
WAD Input Current
2EC
Sink Current
2EC
Off-Leakage Current
PG Sink Current
PG Off-Leakage Current
THERMAL SHUTDOWN
Thermal-Shutdown Threshold
Thermal-Shutdown Hysteresis
T
SD
T
J
rising
T
J
falling
+140
28
NC
NC
I
WAD-LKG
V
WAD-REF
V
WAD
rising, V
IN
= 14V to 48V (referenced
to RTN)
V
WAD
falling, V
RTN
= 0V, V
SS
unconnected
V
WAD
= 10V (referenced to RTN)
V
2EC
= 3.5V (referenced to RTN), V
SS
unconnected
V
2EC
= 48V
V
RTN
= 1.5V, V
PG
= 0.8V, during inrush
period
V
PG
= 48V
125
230
1
1.5
8
9
0.725
3.5
2.25
1
375
1
FA
mA
FA
FA
FA
10
V
I
INRUSH
I
LIM
During initial turn-on period,
V
RTN
= 1.5V
After inrush completed,
V
RTN
= 1V
V
RTN
(Note 9)
90
720
13
135
800
180
880
16.5
mA
mA
V
I
Q
V
ON
V
OFF
V
HYST_UVLO
t
OFF_DLY
t
DELAY
Measured at V
DD
V
IN
rising
V
IN
falling
MAX5969A
MAX5969B
V
IN
falling from 40V to 20V (Note 8)
t
DELAY
= minimum PG current pulse width
after entering into power mode
T
J
= +25NC
R
ON_ISO
I
RTN_LKG
I
RTN
= 600mA
T
J
= +85NC
T
J
= +125NC
V
RTN
= 12.5V to 30V
MAX5969A
MAX5969B
34.3
37.2
30
4.2
7.3
30
80
120
96
0.5
0.65
0.8
10
FA
112
0.7
1
I
0.27
35.4
38.6
60
0.55
36.6
40
V
mA
V
V
V
Fs
ms
SYMBOL
V
THR
V
IN
falling
CONDITIONS
MIN
2.8
TYP
4
MAX
5.2
UNITS
V
Maxim Integrated
3
MAX5969A/MAX5969B
IEEE 802.3af/at-Compliant, Powered Device Interface
Controllers with
Integrated Power MOSFET
ELECTRICAL CHARACTERISTICS (continued)
(V
IN
= (V
DD
- V
SS
) = 48V, R
DET
= 24.9kω, R
CLS
= 619ω. RTN, WAD, PG, and
2EC
unconnected, all voltages are referenced to V
SS,
unless otherwise noted. T
A
= T
J
= -40
N
C to +85
N
C, unless otherwise noted. Typical values are at T
A
= +25
N
C.) (Note 3)
All devices are 100% production tested at T
A
= +25NC. Limits over temperature are guaranteed by design.
The input offset current is illustrated in Figure 1.
Effective differential input resistance is defined as the differential resistance between V
DD
and V
SS
. See Figure 1.
Classification current is turned off whenever the device is in power mode.
UVLO hysteresis is guaranteed by design, not production tested.
A 20V glitch on input voltage that takes V
DD
below V
ON
shorter than or equal to t
OFF_DLY
does not cause the MAX5969A/
MAX5969B to exit power-on mode.
Note 9:
In power mode, current-limit foldback is used to reduce the power dissipation in the isolation MOSFET during an overload
condition across V
DD
and RTN.
Note
Note
Note
Note
Note
Note
3:
4:
5:
6:
7:
8:
I
IN
dR
i
=
1V
(V
INi + 1
- V
INi
)
=
(I
INi + 1
- I
INi
) (I
INi + 1
- I
INi
)
V
INi
dR
i
I
OFFSET
=
I
INi
-
I
INi + 1
I
INi
dR
i
I
OFFSET
V
INi
1V
V
INi + 1
V
IN
Figure 1. Effective Differential Input Resistance/Offset Current
4
Maxim Integrated
MAX5969A/MAX5969B
IEEE 802.3af/at-Compliant, Powered Device Interface
Controllers with
Integrated Power MOSFET
Typical Operating Characteristics
(V
IN
= (V
DD
- V
SS
) = 54V, R
DET
= 24.9kω, R
CLS
= 615ω. RTN, WAD, PG, and
2EC
unconnected; all voltages are referenced to V
SS.
)
INPUT CURRENT (DETECTION)
vs. INPUT VOLTAGE
MAX5969A toc01
SIGNATURE RESISTANCE
vs. INPUT VOLTAGE
MAX5969A toc02
INPUT OFFSET CURRENT
vs. INPUT VOLTAGE
MAX5969A toc03
0.5
0.4
0.3
0.2
0.1
0
0
25.5
R
SIGNATURE
(kI)
INPUT OFFSET CURRENT (µA)
I
IN
= I
VDD
+ I
DET
R
DET
= 24.9kI
RTN = 2EC = PG = WAD = V
DD
-40°C
P
T
A
P
+85NC
26.0
I
IN
= I
VDD
+ I
DET
R
DET
= 24.9kI
RTN = 2EC = PG = WAD = V
DD
T
A
= -40NC
4
2
T
A
= -40NC
T
A
= +85NC
I
IN
(mA)
25.0
T
A
= +25NC
24.5
T
A
= +85NC
0
T
A
= +25NC
-2
24.0
2
4
V
IN
(V)
6
8
10
0
2
4
V
IN
(V)
6
8
10
-4
0
2
4
V
IN
(V)
6
8
10
INPUT CURRENT (CLASSIFICATION)
vs. INPUT VOLTAGE
MAX5969A toc04
CLASSIFICATION SETTLING TIME
MAX5969A toc05
2EC SINK CURRENT vs. 2EC VOLTAGE
V
IN
10V/div
T
A
= -40NC
1.6
1.2
0.8
0.4
0
0
10
20
30
V
2EC
(V)
40
50
60
V
SS
UNCONNECTED
V
2EC
REFERENCED TO RTN
V
WAD
= 14V
T
A
= +85NC
T
A
= +25NC
MAX5969A toc06
70
60
50
I
IN
(mA)
40
30
20
10
0
0
5
10
15
V
IN
(V)
20
25
CLASS 5
2.0
CLASS 3
CLASS 2
CLASS 1
CLASS 0
30
100µs/div
R
CLS
= 30.9
I
I
IN
0A 200mA/div
V
CLS
1V/div
0V
I
2EC
(mA)
CLASS 4
PG SINK CURRENT vs. PG VOLTAGE
MAX5969A toc07
INRUSH CURRENT LIMIT
vs. RTN VOLTAGE
MAX5969A toc08
NORMAL OPERATION CURRENT LIMIT
vs. RTN VOLTAGE
800
CURRENT LIMIT (mA)
700
600
500
400
300
200
MAX5969A toc09
300
T
A
= -40NC
250
200
150
100
50
0
10
20
30
V
PG
(V)
40
50
T
A
= +85NC
T
A
= +25NC
150
130
110
90
70
50
900
INRUSH CURRENT LIMIT (mA)
I
PG
(µA)
100
0
10
20
30
V
RTN
(V)
40
50
60
0
10
20
30
V
RTN
(V)
40
50
60
60
Maxim Integrated
5
测试/测量
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