Features
• Features of the PM8805 PoE-PD interface:
– System in package integrating a double active bridge, a hot-swap MOSFET
and a PoE-PD
– Supports legacy high power, 4-pair applications
– 100 V N-ch MOSFETs with 0.2 Ω total path resistance for each active
bridge
– Identifies which kind of PSE (standard or legacy) it is connected to and
provides successful IEEE 802.3af/at/bt classification indication as a
combination of the T0, T1 and T2 signals (open drain)
– Smart operation mode selection through the STBY, FAUX and RAUX
control signals
– QFN 56 8x8mm package with 43 pins and 6 exposed pads
• Features of the PM8804 PWM controller:
– PWM peak current mode controller
– Input operating voltage up to 75 V
– Internal high voltage start up regulator with 20 mA capability
– Programmable fixed frequency up to 1 Mhz
– Soft startup with settable time
– Soft turn off (optionally disabled)
– Dual 1 APK, low side complementary gate drivers
– GATE2 can be turned off for reduced consumption
– 80% maximum duty cycle with internal slope compensation
– QFN 16 3x3mm package with exposed pad
Description
This reference design represents a 3.3 V, 20 A converter solution ideal for various
applications including wireless access points, supplied with a PoE-PD interface and a
DC-DC active clamp forward converter.
The PoE-PD interface is based on the PM8805 system in package device with two
active bridges and an IEEE 802.3bt compliant Powered Device (PD) interface. It can
be used in all medium-to-high power 2P and 4P high efficiency PoE and PoE+
applications.
The DC-DC active clamp forward converter is designed around the PM8804 PWM
controller, which is an integrated solution for smart and efficient 48 V converters,
featuring a programmable oscillator for the switching frequency, adjustable slope
compensation, dual complementary low-side drivers with programmable dead time,
programmable soft start, soft turn off and a programmable current sense blanking
time.
Product summary
High power PoE PD, 3 V
up to 20 A active clamp
forward evaluation board
STEVAL-
POE006V1
PWM peak current mode
controller for PoE and
telecom systems
PM8804
IEEE802.3bt PoE-PD
interface with integrated
dual-active bridge
PM8805
3.3V/20A, active clamp forward converter, Power Over Ethernet (PoE)
IEEE 802.3bt compliant reference design
STEVAL-POE006V1
Data brief
DB3669 - Rev 3 - June 2019
For further information contact your local STMicroelectronics sales office.
www.st.com
1Schematic diagrams
Figure 1. STEVAL-POE006V1 circuit schematic (1 of 3)
STEVAL-POE006V1
STEVAL-POE006V1 schematic diagrams
DB3669 - Rev 3 page 2/5
Figure 2. STEVAL-POE006V1 circuit schematic (2 of 3)
SLEEP/WKUP
4
VB
R116
SGND
1nF
2
Q14
2N7002
R115
R103
82K
1%
3
BAS70
D51
4
R131
D40
D46
R127
470K
PGD
3
R76
0R
Q13
2N7002
STBY
100K
0805
4
0R-NM
R77
0R
NM
R105
SOD323
R117
R130
1%
1
2
3
D42
3
J10
SOD323
10
R126
C84
BAT46J
0805
D37
SOD323 SOD323
R101
15K
D39
1k
R123
0805
TP-Red
1%
6K8-NM
Raux +live PoE
22nF
C82
5
D45
SMC
1
BAT46J
C81
GND
R132
FAUX
1
2
3
OVP
R75
1k
R119
VOB
D44
C85
20K
SOD323
R121
20K
TP4
0
SOT23-5
1nF
STPS4S200S
R129
TS2431-AILT-NM
0805
3
BAT46J
1% SOT23
CLS1
RAUX_MAN
BAT46J
SOD323
TP1
4k3
NM
1%
RAUX
R128
10K
BAT46J
STBY High
D20
BAT46J
AUXF
RAUX
3
TP3
2.2K-NM
TP-Black
R67
0R-NM
1%
AUX Front
GND
J9
0805
FAUX
D43 D47
BAT46J
P1
U23
TS431AILT
R114
TP-Red
R120
1
SMC
U22
C78
U24
R102
OVP
NM
TP-Black
D52
BAS70-05
SOT23
R118
SS
AUX Rear
R0805
VDC
100k
SOT-23
STBY
TP2
VOUT
4k7
2
P2
R122
47K
NM
1%
FAUX_MAN
100
R104
27K
1%
2
R69
100k
SOD323
AutoClass
2
STPS4S200S
24
1
SOT23
0805 4k7
STBY
SHDN
SOD323
R133
C86
NM
100k
D53
BAS70-05
1
D41
1nF
SOT-23
VB
AUXR
1
GND
FOD817AS
MODE
D14
C83
0805
Figure 3. STEVAL-POE006V1 circuit schematic (3 of 3)
R61
1.5k
PGND
10K
D12
BAS70
1206
TP-Red
S3
VOUT Led
C44
0.1uF
0603
D7
D8
4
C21
2200pF
1812
C37
47uF
1210
L9
PBSS5240T-NM
0603
NC2 7
Q9
200V
STL110NS3LLH7-NM
R108
0R05
D49
BAS70
1K-NM
SGND
22R-NM
TP14
D7
8
VIN
C52
Coilcraft XAL5050-562
C54
2200pF
1812
Q12
TP5
4
BZX84C10-NM
S3
D6
PGND
6
PGD
0805
Auxiliary voltage
Synchronous rectifiers
TP-Black
D1
GSL
100V
Input Filter
0603
1
C39
1nF
R28
150R
U4
S2
TS431AILT
VSN
SOD323
SMA
2
2
D5
POE120PL-xxL_-NM
GSH
10
D7
D8
5
C60
50V
0805
4.7K 1%
C40
47uF
1210
3
S1
FDMC86259P
VSP
LPS4018-105ML
PBSS5240T-NM
PBSS4240T-NM
0805 R17
R4691K
S1
S2
2KV
0805
1%
TP-Red
SGND
Ex Pad
NM
CTL
15
TP-Red
BLK
16QFN_3X3X0.75_0.5
7
MMBT3904LT1-NM
SOT23-5
D8
S2
3
C25
100nF
4
STL110NS3LLH7
200V
C34
2200pF
1812
D8
D8
NC
GAT2 11
C47
2.2uF
25V
1K-NM
G4
0603
100V
820R
BZX84C10-NM
R24
0R
1
VSP
0603
AGND
R25
10K
16V
8x10.5
R55
12k
1%
Q2
STL110NS3LLH7-NM
0805
T4
R48
SOT23
16V
0603
16V
R15
NM
2KV
This circuit goes on the bottom side
under the equivalent circuit on the top side
C
SOT23
1
TP-Red
10K
Q8
220pF
5
NC1
4
1
100V
R54
15K
1%
C30
NM
SS
C33
4.7uF
1210
SGND
GND
PGND
D5
D2
GAT1
PGND 10
R40
100V
Power circuit
G4
TP9
100V
C57
16V
turret
S1
3
SMAJ58A
1206
R27
3M-NM
3
TP10
2KV
TS2431-AILT-NM
BSC190N15NS3
S1
D6
L2
0R
2
SOD323
R32
10R
R53
Q3
0R
NC
2
SGND
SOD323
Fairchild FOD817AS
C29
33uF
100V
R47
R36
10R
100V
powerFLAT 5x6
turret
TP7
R38
10R
C35
1812
2200pF-NM
C26
1nF
0805
R45200K
A
MODE
AGND
EEEFK2A330P
PM8804
U2
VSN
S2
S3
4
5
S3
D6
2KV
2
NM
TP11
PGD
D7
SOD323
SOT23
D7
SS
2
C23
1nF
0805
VC
0805
C20NM
1812
C56
NM
R16
5R6
10x10.2
D13
BAS16J
10k
SER2011-202L
TP-Black
TP12
0805
Q4
R51
12R
TP-Red
S1
S2
R26
0R
C96
2.2uF
25V
GSL
D11
C27
NM
C75
100pF-NM
0805
0805
47K
C59
1
Feedback circuit
AGND
VSP
2
NC
SOD323
1210
C38
47uF
1210
J4
SOT23
100pF
C55
100nF
25V
C53 33nF
S1
S2
SGND
D6
D7
A
SOT23
BZX84C10-NM
MODE
13
MA5509-BL
9
2
1
S3
STL110NS3LLH7
D5
L4
PBSS4240T-NM
T2
0603
D6
R35
R49
SOT23
0603
6
R43130K
1210
22nF
1
1
D9
BAS16J
TP-Red
R44
0R22
Q7
0603
SGND
D5
Q10
C28
NM R56
C43
330uF
TP6
R124
10R
D6
G4
0805
25V
0805
Q11
16V
T3
D17
C36
47uF
1210
R33
5R6
0805
C51
1nF
0805
C48
47nF
1206
1
11
8
U3
16V
D8
100V
12
1
2KV
SOT23
A
R34
BAS16J
VDC
Chassis
C31
4.7uF
1210
4FSW
12
DT
3
C58
PowerFLAT 5x6
PowerFLAT 5x6
SOT23
PowerFLAT 5x6
J6
0805
C32
4.7uF
1210
1
2
R31
NM
L1
5.6uH
SOT23
D16
BAS16J
100nF
22nF
VOUT
2KV
C22
2200pF-NM
1812
D8
R78
0R
2K
Q5
2010
G4
R50
220R
1%
8
R41NM
C42
47uF
1210
R37
50V
U12
R29
1206
C50
100nF
25V
1mH
6
R125
TP13
3
SGND
G4
C24
4.7uF
1210
R52
20k
2
1206
GSH
17
0805
powerFLAT 5x6
16V
D5
CS
14
PGND
SGND
C
16
5
Q1
D48
BAS16J
C49
NM
1206
SOD323
SOD323
C41
47uF
1210
D5
D15
S3
C
2
100V
22R-NM
TP8
VSN
G4
2
1
R30
NM
L3
0R
R62
NM
10
9
SOD323
C76
100pF-NM
0805
0805
C46
1nF
0805
D50
BAS70
C95
1nF
C45
100nF
25V
STEVAL-POE006V1
STEVAL-POE006V1 schematic diagrams
DB3669 - Rev 3 page 3/5
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© 2019 STMicroelectronics – All rights reserved
STEVAL-POE006V1
DB3669 - Rev 3 page 5/5
