High power Poe PD, 3V3 up to 20 A active clamp forward ...€¦ · When RAUX power supply is...
Transcript of High power Poe PD, 3V3 up to 20 A active clamp forward ...€¦ · When RAUX power supply is...
IntroductionThe STEVAL-POE006V1 evaluation board allows an easy verification of a PD interface compliant with the new IEEE802.3btstandard based on PM8805 and of a DC-DC active clamp forward converter based on PM8804 controller.
The PM8805 is a highly integrated device embedding two active bridges and an IEEE802.3bt compliant powered device (PD)interface. It can be successfully used in all medium to high power, 2P and /or 4P high efficiency PoE/ PoE+ applications.
The PM8804 is a PWM controller that integrates all the circuitry required to design a smart and efficient 48 V converter.
It features a programmable oscillator for the switching frequency, adjustable slope compensation, dual complementary low-sidedrivers with programmable dead time and soft start, soft turn off and a programmable current sense blanking time.
Figure 1. STEVAL-POE006V1 evaluation board
High power Poe PD, 3V3 up to 20 A active clamp forward evaluation board
AN5237
Application note
AN5237 - Rev 1 - December 2018For further information contact your local STMicroelectronics sales office.
www.st.com
1 STEVAL-POE006V1 evaluation board overview
1.1 Specifications, connectors and LEDs
Table 1. STEVAL-POE006V1 specifications
Parameter Specs
VIN at RJ45 connector From 41.2 to 57 V
IIN at RJ45 connector 1.0 A max. each pair
VOUT 3.3 V ± 2%
IOUT 20 A total max.
Max. ouput power 66 W max.(1)
Efficiency overall peak>90% at IOUT=10 A, at VIN= 48 V
>89% at IOUT=20 A, at VIN= 48 V
VIN at Frontal Jack connector (J9) 48 V ±2 V
IIN at Frontal Jack connector (J9) 1.5 A total max.
VIN at Rear Jack connector (J10) 48 V ±2 V
IIN at Rear Jack connector (J10) 1.5 A total max.
Operating temperature0°C - 50°C 20 A full load
50°C - 85°C linearly decrease to 15 A
1. Max. power cannot be maintained at high ambient temperature ( Tamb>50°C) for a long time.
Table 2. STEVAL-POE006V1 connectors
Reference Type Specs
J1 RJ45 connector Data and power input
J2 RJ45 connector Data output
J9 Power jack Front Aux
J10 Power jack Rear Aux
J4, TP10 Banana jack/turret Positive of VOUT
J6, TP11 Banana jack/turret Negative of VOUT (Sec GND)
TP8 Test point Monitor of VOUT
TP9 Test point Monitor of Sec GND
P1 Push button SLEEP/WKUP
P2 Push button SHDN
AN5237STEVAL-POE006V1 evaluation board overview
AN5237 - Rev 1 page 2/45
Table 3. STEVAL-POE006V1 LEDs
Reference Type Function Logic
D4 Green LED Monitor of T2 signal LED on when T2 is low
D5 Green LED Monitor of T1 signal LED on when T1 is low
D6 Green LED Monitor of T0 signal LED on when T0 is low
D15 Green LED Monitor of VOUT LED on when VOUT is present
D39 Green LED Monitor of FAUX signal LED on when frontal aux is present
D40 Green LED Monitor of STBY signal LED on when STBY is high
D44 Green LED Monitor of RAUX signal LED on when rear aux is present
Table 4. Tx signal possible configurations
Classification T0 T1 T2 Bridges Finger number Notes
Type 1 (13 W) 1 1 1 1 0 or 1 Legacy type
Type 2 (25.5 W) 0 1 1 1 2, 3 Legacy type
Type 3 (51 W) 1 0 0 2 4 New PD type
Type 4 (71 W) 0 0 0 2 ≥ 5 New PD type
Type 3 on 4 pairs (13 W), or legacy 4 pairs (type 1 class) 1 1 0 2 0 or 1 New PD type
Type 3 on 4 pairs (25.5 W), or legacy 4 pairs (type 2 class) 0 1 0 2 2, 3 New PD type
Rear AUX0 0 1
anyN.A. Aux present
Front AUX 0
The STEVAL-POE006V1 evaluation board is classified as type 4 and class 8. The default status of Tx signal is000.
Note: Level 0 or low means the corresponding LED is on; level 1 or high means the LED is off.
AN5237Specifications, connectors and LEDs
AN5237 - Rev 1 page 3/45
1.2 Board setupThe STEVAL-POE006V1 evaluation board combines the PM8805 PD interface, compliant with the IEEE 802.3btPoE standard, and the PM8804 PWM controller for an active clamp forward.
Figure 2. STEVAL-POE006V1 evaluation board: components view
• 1. POE IN• 2. RAUX IN• 3. FAUX IN• 4.SLEEP and WAKEUP• 5.SHUTDOWN• 6.OUTPUT
When you use a bench power supply, follow the steps below.
Step 1. Set the power supply current limit to 0.2 AStep 2. Apply 10 V and check the input current is 350-400 µAStep 3. Apply 20 V and check the input current is within the selected Class range (the default is Class 8, 39
mA)Step 4. Apply 48 V and check the input current is <50 mA and the output voltage is 3.3 V (without load)Step 5. Change the current limit to 3 AStep 6. Connect an electronic load between VOUT and the secondary GNDStep 7. Turn the power supply on (48 V) and check the input current is coherent with the load current setting
and the converter expected efficiency.For example, 3.3 V x 10 A = 33 W→expected efficiency is 91% so PIN = 33/0.91=36.2 W, which, with48 V as input voltage, gives Iinput =36.2/48 =0.75 A
Step 8. Change the load current as needed
AN5237Board setup
AN5237 - Rev 1 page 4/45
2 Configurations
2.1 PM8805 configurations
Table 5. PM8805 control signal description
PM8805 behavior,standardoperations
INPUTS OUTPUTS
FAUX RAUX STBY PGD Hot swap Chargepump Active bridge MPS
Normal POE operation 0 0 0 1 after 85ms hotswap enabled
Closes atUVLO On @ UVLO Enabled Off
Stby PoE operation 0 0 1 1 when hotswap closed
Closes atUVLO Off LS enabled HS
OFF On
Front Aux operation 1 0 x 1 when hotswap closed Closed On Enabled Off
Rear Aux operation 0 1 0 1 Open Off Off Off
Additional non standard operations
Sleep mode/Wake up 1 1 1 0 Open Off LS enabled HSOFF On
Rear Aux with MPS 0 1 1 1 Open Off LS enabled HSOFF On
Shutdown/reboot 1 1 0 0 Open Off Off Off
2.2 PoEThe STEVAL-POE006V1 evaluation board default operation mode is the PoE (0,0,0). The selected class resistorsare 36.5 ohm for CLS1 and 51.1 ohm for CLS2, so the board is class 8; that is, the Tx LED configuration is 000 orall LEDs on.The other classes can be adjusted using the following table.
Table 6. PM8805 class description
PD class CLS1 resistor (Ω) CLS2 resistor (Ω) Min. (mA) Max. (mA)
Class 0 2 K 2 K 0 4.0
Class 1 150 150 9.0 12.0
Class 2 80.6 80.6 17.0 20.0
Class 3 51.1 51.1 26.0 30.0
Class 4 36.5 36.5 36.0 44.0
Class 5 36.5 2 K 36/0 44/4
Class 6 36.5 150 36/9 44/12
Class 7 36.5 80.6 36/17 44/20
Class 8 36.5 51.1 36/26 44/30
Classification phase is valid only for PoE devices, so it is not required when connected to any non-PoE powersource such as a wall adapter: in those cases, the CLS buffers are never turned on.Depending on the PD type and class, the relevant PD electrical parameters are summarized in the table below.
AN5237Configurations
AN5237 - Rev 1 page 5/45
Table 7. PM8805 PD main parameters
PD type Class CLS1 sign. CLS2 sign. Pin (W) Vin min. (V) Vin max. (V) IIN max. (mA) Ppeak (W) for 50 ms
1
0 0 0 13.0 37.0
57
350 14.4
1 1 1 3.84 42.1 90 5.00
2 2 2 6.49 40.8 160 8.36
3 3 3 13.0 37.0 350 14.4
2 4 4 4 25.5 42.5 600 28.05
3
1 1 1 3.84 42.1 90 5.00
2 2 2 6.49 40.8 160 8.36
3 3 3 13.0 37.0 350 14.4
4 4 4 25.5 42.5 600 28.05
5 4 0 40.0 44.3 900 42
6 4 1 51.0 42.5 1200 53.55
47 4 2 62.0 42.9 1440 65.10
8 4 3 71.3 41.2 1730 74.86
2.3 FAUX connectorA voltage applied at J9 connector (FAUX) sets automatically the correct input configuration (FAUX=1, RAUX=0,STBY=do not care).If the STEVAL-POE006V1 evaluation board is already powered by a PSE, the following conditions apply:1. FAUX voltage lower than PSE voltage: the evaluation board is still powered from PSE and T0,T1,T2 signal
configuration remains the same according to Table 4. Tx signal possible configurations2. FAUX voltage is greater than PSE voltage, but the difference is less than 2 V: a current sharing occurs
between PSE and FAUX to supply the evaluation board. T0,T1,T2 signal configuration remains unchangedas in the previous case
3. FAUX voltage is greater than PSE voltage and the difference is greater than 2 V: the evaluation board ispowered by FAUX, PSE is disconnected as its load has significantly decreased (~3 mA) and PD does notensure MPS condition.The PM8805 device works in Front aux mode (T0=0,T1=0,T2=1). When the FAUX connector (J9) isunplugged, PSE is not connected and the output voltage is interrupted as a new detection/classificationprocedure must be done before PSE powers the board again.
2.4 RAUX with MPSA voltage applied at J10 connector (RAUX) sets automatically the correct input configuration (FAUX=0; RAUX=1;Stby=1).The hot swap is opened to give prevalence of the RAUX source over the PoE interface.The STEVAL-POE006V1 evaluation board is configured to put the PSE in MPS mode triggering the STBY pinthreshold by a proper divider (R69, R76 and R120) supplied by the RAUX input voltage. When STBY pin is pulledup, MPS current is enabled and drawn from the PSE.The RAUX voltage can be in one of the following ranges, depending on the PSE voltage available at RJ45connector (J1):• RAUX voltage lower than PSE input voltage of less than 8 V: when RAUX voltage is applied and the
evaluation board is already powered by PSE, switching between the two power supply sources worksproperly. The PM8805 device goes in Rear auxiliary with MPS mode and PSE remains connected to theevaluation board (T0=0,T1=0, T2=1)
AN5237FAUX connector
AN5237 - Rev 1 page 6/45
Figure 3. PSE to RAUX switchover at VPSE=55 V, VRAUX=48 V, IOUT=17 A
– Ch1: VDC input voltage (TP5); Ch2: PSE input current (J1 twisted pairs)– Ch3: RAUX signal (pin 11 U1 - PM8805); Ch4: RAUX input current (J10)
When RAUX power supply is unplugged from J10, PSE is immediately available to supply the evaluationboard, without causing output voltage interruptions, and the PM8805 device goes back to normal operatingmode.As shown in the figure below, there is a delay of about 200 µs between the time the RAUX source isunplugged and the hot swap MOSFET of PM8805 is turned on again, during which the forward converter issupplied only by input capacitors C29 and C15.
AN5237RAUX with MPS
AN5237 - Rev 1 page 7/45
Figure 4. RAUX to PSE switchover at VPSE=55 V, VRAUX=48 V, IOUT=17 A
– Ch1: VDC input voltage (TP5); Ch2: PSE input current (J1 twisted pairs)– Ch3: Raux signal (pin 11 U1 – PM8805); Ch4: RAUX input current (J10)
• RAUX voltage lower than PSE input voltage of more than 12 V: when RAUX voltage is applied and theevaluation board is already powered by PSE, switching between the two power supply sources worksproperly as in the previous case. When RAUX power supply is unplugged from J10, during the switchover,the PM8805 hot swap MOSFET drop between drain and source might be greater than the datasheetparameter Vds_fail (12 V min./16 V max.), or the hot swap MOSFET current might be greater than thedatasheet parameter Short (4 A min./6 A max.).If the above mentioned failures occur, the power good signal is forced to low level according to the datasheetparameter Tretry (9 min./11 max. msec), stopping the forward converter switching, then it is releasedcausing an output voltage interruption as shown in the following figure.
AN5237RAUX with MPS
AN5237 - Rev 1 page 8/45
Figure 5. RAUX to PSE switchover at IOUT=17 A
– Ch1: VDC input voltage (TP5); Ch2: PGD signal (TP19)– Ch3: RAUX signal (pin 11 U1-PM8805); Ch4: Vout output voltage (TP8)
• RAUX voltage is greater than PSE input voltage of at least a diode forward voltage: when RAUX voltage isapplied and the evaluation board is already powered by PSE, switching between the two power supplysources works properly as reported in the previous cases, but in this condition MPS current is drawn byRAUX source, then PSE is no more able to stay connected to evaluation board. In this case, when RAUXsource is removed, the output voltage goes to zero until PSE has successfully completed detection andclassification phases, and the voltage is reapplied to the PD interface.
2.5 Soft stopAn important feature of the PM8804 is the soft stop that can be controlled via the MODE pin, used to select theconverter operation mode.By connecting this pin to AGND, you can turn GATE2 off when not used and disable the soft stop feature.Pull up MODE pin if GATE2 is used and soft stop desired. Leave this pin open when not used.In case of normal shutdown or thermal fault, the device features a soft stop procedure which helps to reduce thestress and the overvoltage on the power MOSFET and it is achieved discharging slowly the soft start capacitorwith a 10 µA current sink. On the STEVAL-POE006V1 evaluation board the MODE pin is left open, as GATE2must be available to implement the active clamp forward converter and, during normal shutdown, the soft stopprocedure is implemented.
AN5237Soft stop
AN5237 - Rev 1 page 9/45
3 Measurements
3.1 EfficiencyThe STEVAL-POE006V1 evaluation board is composed of a PoE interface compliant with the last standardIEEE802.3bt, with the PM8805 interface and a forward active clamp DC-DC converter that receives DC voltagefrom the PoE interface.The figure below shows the efficiency of a single forward converter and the overall efficiency which also includesthe PoE interface power losses.
Figure 6. STEVAL-POE006V1 overall and DC-DC forward efficiency
The dotted lines indicate the STEVAL-POE006V1 efficiency at different DC input voltages applied to RJ45connector J1. The continuous line indicates the DC-DC forward efficiency, that does not include the followinglosses of the associated POE interface section:• RJ45 connector J1• PoE data transformer T1• common chokes T7 and T8 placed on the two power supply pairs• PM8805 interface that integrates the dual power MOS bridges and a hot swap MOSFET• Forward converter input filter
This efficiency is measured between output test points TP8/TP9 and input test points TP5/TP6 of the forwardconverter.
AN5237Measurements
AN5237 - Rev 1 page 10/45
3.2 Output voltage ripple
Figure 7. Output voltage ripple: IOUT= 2 A
• Ch1: Vout ripple; Ch2: Primary MOSFET gate voltage; Ch3: IOUT
AN5237Output voltage ripple
AN5237 - Rev 1 page 11/45
Figure 8. Output voltage ripple: IOUT= 20 A
• Ch1: Vout ripple; Ch2: Primary MOSFET gate voltage; Ch3: IOUT
AN5237Output voltage ripple
AN5237 - Rev 1 page 12/45
3.3 Input voltage ripple
Figure 9. Input voltage ripple before and after forward input filter: VIN = 48 V, IOUT =2 A
• Ch1: Vin ripple before input filter (TP5); Ch2: Primary MOSFET gate voltage• Ch4: Vin ripple after input filter (C33); Ch3: Input current (J1 connector pairs)
AN5237Input voltage ripple
AN5237 - Rev 1 page 13/45
Figure 10. Input voltage ripple before and after forward input filter: VIN = 48 V, IOUT =20 A
• Ch1: Vin ripple before input filter (TP5); Ch2: Primary MOSFET gate voltage• Ch4: Vin ripple after input filter (C33); Ch3: Input current (J1 connector pairs)
AN5237Input voltage ripple
AN5237 - Rev 1 page 14/45
3.4 Startup
Figure 11. Output voltage at startup: Iout at no load, Vin= 48 V
• Ch1: Vout; Ch2: Soft start voltage (C53); Ch4: primary MOSFET gate voltage
AN5237Startup
AN5237 - Rev 1 page 15/45
Figure 12. Output voltage at startup: Iout=20 A, Vin= 48 V
• Ch1: Output voltage; Ch2: Soft start voltage (C53);Ch4: Output current; Ch3: primary MOSFET gate voltage
AN5237Startup
AN5237 - Rev 1 page 16/45
3.5 PoE connector unplugged power off
Figure 13. Power off at primary side: Iout=20 A, Vin= 42 V
• Ch1: Primary Q4 MOSFET drain voltage; Ch2: Forward input voltage (TP5)• Ch3: Soft start voltage (C53); Ch4: Power good (TP19)
AN5237PoE connector unplugged power off
AN5237 - Rev 1 page 17/45
Figure 14. Power off at secondary side (Q1): Iout=20 A, Vin= 42 V
• Ch1: Primary Q4 MOSFET drain voltage; Ch2: Secondary Q1 MOSFET gate voltage• Ch3: Secondary Q1 MOSFET drain voltage; Ch4: Power good (TP19)
AN5237PoE connector unplugged power off
AN5237 - Rev 1 page 18/45
Figure 15. Power off at secondary side (Q5): Iout=20 A, Vin= 42 V
• Ch1: Primary Q4 MOSFET drain voltage; Ch2: Secondary Q5 MOSFET gate voltage• Ch3: Secondary Q5 MOSFET drain voltage; Ch4: Power good (TP19)
AN5237PoE connector unplugged power off
AN5237 - Rev 1 page 19/45
3.6 Primary side waveforms
Figure 16. Primary steady state: Iout=2 A, Vin= 48 V
• Ch1: Primary Q4 MOSFET drain voltage; Ch2: Primary current sense voltage• Ch4: Primary MOSFET gate voltage
AN5237Primary side waveforms
AN5237 - Rev 1 page 20/45
Figure 17. Primary steady state: Iout=20 A, Vin= 48 V
• Ch1: Primary Q4 MOSFET drain voltage; Ch2: Primary current sense voltage• Ch4: Primary MOSFET gate voltage
AN5237Primary side waveforms
AN5237 - Rev 1 page 21/45
3.7 Secondary side waveforms
Figure 18. Secondary steady state: Iout=2 A, Vin= 48 V
• Ch1: Secondary Q1 MOSFET drain voltage; Ch2: Secondary Q5 MOSFET drain voltage• Ch3: Secondary Q1 MOSFET gate voltage; Ch4: Secondary Q5 MOSFET gate voltage
AN5237Secondary side waveforms
AN5237 - Rev 1 page 22/45
Figure 19. Secondary steady state: Iout=20 A, Vin= 48 V
• Ch1: Secondary Q1 MOSFET drain voltage; Ch2: Secondary Q5 MOSFET drain voltage• Ch3: Secondary Q1 MOSFET gate voltage; Ch4: Secondary Q5 MOSFET gate voltage
AN5237Secondary side waveforms
AN5237 - Rev 1 page 23/45
3.8 Load transient side waveforms
Figure 20. Load transient: IOUT=10 to 20 A, Vin= 48 V
• Ch1: Output voltage; Ch2: Output current
AN5237Load transient side waveforms
AN5237 - Rev 1 page 24/45
3.9 Gloop measurements
Figure 21. Gloop plot (VIN= 48 V, IOUT=1 A)
Figure 22. Gloop plot (VIN= 48 V, IOUT=10 A)
Figure 23. Gloop plot (VIN= 48 V, IOUT=20 A)
AN5237Gloop measurements
AN5237 - Rev 1 page 25/45
3.10 Thermal analysisThermal analysis has been performed by supplying the STEVAL-POE006V1 evaluation board via a power supplyat 48 V, setting different levels of load current.The emissivity is 0.95, the reflected temperature is 20.0 °C.
Figure 24. STEVAL-POE006V1 thermography at IOUT=20 A, VIN=41 V
Table 8. STEVAL-POE006V1 measurements for IOUT=20 A, VIN=41 V
Measurements Temperature
Sp1 -Q5 secondary freewheeling MOSFET 103.7 °C
Sp2- Q1 secondary rectifier MOSFET 100.3 °C
Sp3 - Q4 primary main MOSFET 78.2 °C
Sp4- T3 forward transformer 78.5 °C
Sp5- L4 output inductor 79.8 °C
Sp6 - U1 PM8805 60.0 °C
AN5237Thermal analysis
AN5237 - Rev 1 page 26/45
Figure 25. STEVAL-POE006V1 thermography at IOUT=20 A, VIN=56 V
Table 9. STEVAL-POE006V1 measurements for IOUT=20 A, VIN=56 V
Measurements Temperature
Sp1 -Q5 secondary freewheeling MOSFET 113.0 °C
Sp2- Q1 secondary rectifier MOSFET 101.1 °C
Sp3 - Q4 primary main MOSFET 79.9 °C
Sp4- T3 forward transformer 79.3 °C
Sp5- L4 output inductor 82.1 °C
Sp6 - U1 PM8805 56.1 °C
AN5237Thermal analysis
AN5237 - Rev 1 page 27/45
4 STEVAL-POE006V1 schematic diagrams
Figure 26. STEVAL-POE006V1 circuit schematic (1 of 3)
AN5237STEVAL-POE006V1 schematic diagrams
AN5237 - Rev 1 page 28/45
Figure 27. STEVAL-POE006V1 circuit schematic (2 of 3)
SLEEP/WKUP
4
VB
R116
SGND
1nF
2
Q142N7002
R115
R10382K1%
3
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S70D51
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R131
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D46
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R770R
NMR105
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R117
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123
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TS2431-AILT-NM
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GN
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J9
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D43 D47
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TP-Red
R120
1
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U22
C78
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R102
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D52BAS70-05
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R118
SS
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R0805
VDC
100k
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TP2
VOUT
4k7
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R12247K
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100
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D41
1nF
SOT-23
VB
AUXR
1
GND
FOD817AS
MODE
D14
C83
0805
Figure 28. STEVAL-POE006V1 circuit schematic (3 of 3)
R611.5k
PGND
10K
D12BAS70
1206
TP-Red
S3
VOU
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C440.1uF0603
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NC
27
Q9
200V
STL110NS3LLH7-NM
R1080R05
D49BAS70
1K-NM
SGND
22R-NM
TP14
D7
8V
IN
C52
Coilcraft XAL5050-562
C542200pF
1812
Q12
TP5
4
BZX84C10-NM
S3
D6
PGND
6P
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0805
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Synchronous rectifiers
TP-Black
D1
GSL
100V
Input Filter
0603
1
C391nF
R28150R
U4
S2
TS431AILT
VSNSOD323
SMA
2
2
D5
POE120PL-xxL_-NM
GSH
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D8
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C60
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C4047uF1210
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FDMC86259P
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LPS4018-105ML
PBSS5240T-NM
PBSS4240T-NM0805 R17
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S1
S2
2KV
0805
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TP-Red
SGND
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CTL
15
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16QFN_3X3X0.75_0.5
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2KV
This circuit goes on the bottom sideunder the equivalent circuit on the top side
C
SOT23
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10K
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220pF
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C1
41
100V
R5415K1%
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SS
C33
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SGND
GND
PGND
D5
D2
GAT1
PGND10
R40
100V
Power circuit
G4
TP9
100V
C57
16V
turret
S1
3
SMAJ58A
1206
R273M-NM
3
TP10
2KV
TS2431-AILT-NM
BSC190N15NS3
S1
D6
L2
0R
2
SOD323
R3210R
R53
Q3
0R
NC
2
SGND
SOD323
Fairchild FOD817AS
C2933uF100V
R47
R3610R
100V
powerFLAT 5x6
turret
TP7
R3810R
C35
18122200pF-NM
C261nF0805
R45200K
A
MODE
AGND
EEEFK2A330P
PM8804
U2
VSN
S2
S3
4
5
S3
D6
2KV
2
NM
TP11
PGD
D7
SOD323
SOT23
D7
SS2
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VC
0805
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1812
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2
NC
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C3847uF1210
J4
SOT23
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C53 33nF
S1
S2
SGND
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D7
A
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13
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9
21
S3
STL110NS3LLH7
D5
L4
PBSS4240T-NM
T2
0603
D6
R35
R49
SOT23
0603
6
R43130K
1210
22nF
1
1
D9BAS16J
TP-Red
R440R22
Q7
0603
SGNDD
5
Q10
C28NM R56
C43330uF
TP6
R12410R
D6
G4
0805
25V
0805
Q11
16V
T3
D17
C3647uF1210
R335R6
0805
C511nF0805
C4847nF
1206
1
11
8
U3
16V
D8
100V
12
1
2KV
SOT23
AR34
BAS16J
VDC
Chassis
C31
4.7uF1210
4FSW
12
DT3
C58
PowerFLAT 5x6
PowerFLAT 5x6
SOT23
PowerFLAT 5x6
J6
0805
C32
4.7uF1210
1
2
R31NM
L1
5.6uH
SOT23
D16BAS16J
100nF
22nF
VOUT
2KV
C222200pF-NM1812
D8
R780R
2K
Q5
2010
G4
R50220R1%
8
R41NM
C4247uF1210
R37
50V
U12
R29
1206
C50100nF25V
1mH
6
R125
TP13
3
SGND
G4C24
4.7uF1210
R5220k
21206
GSH
17
0805powerFLAT 5x6
16V
D5
CS
14
PGND
SGND
C
16
5
Q1
D48BAS16J
C49NM1206
SOD323
SOD323
C4147uF1210
D5
D15
S3
C
2
100V
22R-NM
TP8
VSN
G4
2
1
R30NM
L3
0R
R62NM
10
9
SOD323
C76100pF-NM0805
0805C461nF0805
D50BAS70
C951nF
C45100nF25V
AN5237STEVAL-POE006V1 schematic diagrams
AN5237 - Rev 1 page 29/45
5 Bill of materials
Table 10. STEVAL-POE006V1 bill of materials
Item Q.ty Ref. Part/Value Description Manufacturer Order code
1 1 C43 330 µF, 16 VAluminiumElectrolyticcapacitor
Panasonic EEEFK1C331GP
2 2 C15, C29 33 µF, 100 VAluminiumElectrolyticcapacitor
Panasonic EEEFK2A330P
3 2 C11, C12 1 nF, 250 V,C0805 Capacitor Any
4 2 C13, C17 100 nF, 100 V,C0805 Capacitor Any
5 5C25, C44,C45, C50,C58
100 nF, 25 V,C0603 Capacitor Any
6 1 C52 100 pF, 25 V,C0603 Capacitor Any
7 4 C1, C2, C3,C4 10 nF, 250 V Capacitor TDK C2012X7R2E103K125
AA
8 1 C14 10 nF, 100 V,C0603 Capacitor Any
9 1 C10 1 nF, 2KV, C1812 Capacitor Any
10 6C23, C26,C39, C46,C51, C95
1 nF, 100 V,C0805 Capacitor Any
11 4 C61, C62,C63, C64
1 nF, 250 V,C0805 Capacitor Any
12 3 C82, C83,C84
1 nF, 100 V,C0603 Capacitor Any
13 1 C5 2.2 nF, 2KV,C1812 Capacitor Any
14 1 C18 2.2 nF, 100 V,C0603 Capacitor Any
15 2 C47, C96 2.2 µF, 25 V,C0603 Capacitor Any
16 4 C21, C34,C35, C54
2200 pF, 2KV,C1812 Capacitor Any
17 1 C59 220 pF, COG, 25V, C0603 Capacitor Any
18 3 C57, C60,C81
22 nF, COG, 25 V,C0603 Capacitor Any
19 1 C53 33 nF, 25 V,C0603 Capacitor Any
20 5C16, C24,C31, C32,C33
4.7 µF, 100 V,C1210 Capacitor Any
21 1 C48 47 nF, 200 V,C1206 Capacitor Any
AN5237Bill of materials
AN5237 - Rev 1 page 30/45
Item Q.ty Ref. Part/Value Description Manufacturer Order code
22 6C36, C37,C38, C40,C41, C42
47 µF, 16 V C1210 Capacitor Murata GRM32ER61C476ME15
23 1 C19 68 nF, 100 V,R0805 Capacitor Any
24 4 C6, C7, C8,C9 1 nF, 2KV, C1812 Capacitor (not
mounted) TDK
25 1 C55 100 nF, 25 V,C0603
Capacitor (notmounted) Any
26 2 C75, C76 100 pF, 50 V,C0805
Capacitor (notmounted) Any
27 8
C87, C88,C89, C90,C91, C92,C93, C94
10 nF, 1 KV,C1210
Capacitor (notmounted) AVX 1210AC103KAT1A
28 2 C20, C22 2200 pF, 2KV,C1812
Capacitor (notmounted) AVX
29 4 C27, C28,C30, C86 100 V, C0805 Capacitor (not
mounted) Any
30 1 C49 200 V, C1206 Capacitor (notmounted) Any
31 1 C56 C0603 Capacitor (notmounted) Any
32 1 C78 25 V, C0603 Capacitor (notmounted) Any
33 2 T7, T8 RN102 Common Choke Schaffner RN 102-2-02-1M1
34 1 T2 RN112 Common Choke(not mounted) Schaffner RN 112-4-02-0M7
35 2 T5, T6 Common Choke(not mounted)
WurthElektronik 744272471
36 2 J4, J6 BANANA-JACK Connector Any
37 1 J1 DATA & POWERINPUT Connector Bell Stewart SS-7188S-A-NF
38 1 J2 DATA OUTPUT Connector Bell Stewart SS-7188S-A-NF
39 1 U1
IEEE802.3bt PoE-PD interface withintegrated dual-active-bridge
ST PM8805TR
40 1 U2
PWM peak currentmode controller forPoE and telecomsystems
ST PM8804TR
41 1 T1 POE Trafo Data Trafo WurthElektronik 7490220123
42 1 T1 POE Trafo Data Trafo Coilcraft WA8704-ALD
43 12
D1, D9, D13,D16, D48,D14, D20,D37, D43,D45, D46,D47
SOD-323 Small signalSchottky diode ST BAT46J
AN5237Bill of materials
AN5237 - Rev 1 page 31/45
Item Q.ty Ref. Part/Value Description Manufacturer Order code
44 1 D3 SOT23
Low capacitance,low seriesinductance andresistanceSchottky diodes
ST BAS70
45 4 D12, D49,D50, D51 SOD-323 Diode ST BAS70
46 2 D41, D42 SMC Power Schottkyrectifier ST STPS4S200S
47 1 D2, D17 SOT23 Diode (notmounted) Any
48 2 D7, D8 SMA 400 W TVS inSMA ST SMAJ58A
49 2 D52, D53 SOT-23 Dual DiodeCommon Anodes ST BAS70-05FILM
50 4 L5, L6, L7, L8 220 R, 0805 Ferrite beads TDK MPZ2012S221AT000
51 1 L4 2.0 µH Inductor TDK SER2011-202L
52 1 L1 POWERINDUCTOR Inductor Coilcraft XAL5050-562
53 1 L1 POWERINDUCTOR
Inductor (notmounted)
WurthElektronik 74439346056
54 1 D39 FAUX LED Diode Kingbright AA3528CGSK
55 1 D44 RAUX LED Diode Kingbright AA3528CGSK
56 1 D40 STBY LED Diode Kingbright AA3528CGSK
57 3 D4, D5, D6 T0, T1, T2 LED Diode Kingbright AA3528CGSK
58 1 D15 VOUT LED LED Diode Any
59 1 L9 Low Profile Powerinductor Coilcraft LPS4018-105ML
60 2 Q13, Q14 2N7002 SOT23 N channel Mosfet Any
61 1 U3 Optocoupler Fairchild FOD817AS
62 1 U22 Optocoupler Fairchild FOD817AS
63 1 T4Planar PowerTrafo (notmounted)
Coilcraft
64 1 J9 AUX Front Power Jack Switchcraft P-JACK-RAPC722
65 1 J10 AUX Rear Power Jack Switchcraft P-JACK-RAPC722
66 1 Q4BSC190N15NS3
Power MOSFETInfineon BSC190N15NS3
SiJ494DP Siliconix SiJ494DP
67 2 Q1, Q5 STL110NS3LLH7 Power MOSFET ST STL110NS3LLH7
68 2 Q2, Q8 STL110NS3LLH7 Power MOSFET(not mounted) ST STL110NS3LLH7
69 1 T3 Power Trafo Coilcraft MA5509-BL
70 1 P2 SHDN Push Button Bourns push-7914-bourns
71 1 P1 SLEEP/WKUP Push Button Bourns push-7914-bourns
72 1 R126 10 R, 0603 Resistor Any
73 2 R76, R77 0 R, R0805 Resistor Any
AN5237Bill of materials
AN5237 - Rev 1 page 32/45
Item Q.ty Ref. Part/Value Description Manufacturer Order code
74 1 R78 0 R, R1206 Resistor Any
75 2 L2, L3 0R0, 0805 Resistor Any
76 1 R9 0R0, R1210 Resistor Any
77 2 R24, R26 0R0, R1206 Resistor Any
78 2 R49, R131 0R0, R0603 Resistor Any
79 1 R107 0R0, R0805 Resistor Any
80 1 R108 0R050, R1210 Resistor Any
81 1 R44 0R220, R1210,±1% Resistor Any
82 3 R69, R115,R116 100 k, R0805 Resistor Any
83 1 R133 100 K, R0603 Resistor Any
84 1 R102 100 R, R0603 Resistor Any
85 4 R25, R37,R40, R56 10 K, R0603 Resistor Any
86 1 R128 10 K, R0603, ±1% Resistor Any
87 4 R32, R36,R38, R124 10 R, R0805 Resistor Any
88 1 R55 12 K, R0603, ±1% Resistor Any
89 1 R48 12 R, R0603, ±1% Resistor Any
90 1 R43 130 K, R0603,±1% Resistor Any
91 1 R28 150 R, R0603 Resistor Any
92 1 R101 15 K, R0603, ±1% Resistor Any
93 2 R75, R123 1 K, R0805 Resistor Any
94 1 R61 1K5, R0805 Resistor Any
95 1 R45 200 K ±1% R0603 Resistor Any
96 2 C85, R121 20 K, 100 V,R0805 Resistor Any
97 1 R52 20 k, ±1%, R0603 Resistor Any
98 1 R50 220 R, ±1%,R0603 Resistor Any
99 1 R14 26.1 K, ±1%,R0603 Resistor Any
100 1 R104 27 K, ±1%, R0603 Resistor Any
101 1 R47 2 K, R0603 Resistor Any
102 3 R18, R19,R20 3.9 K, R0603 Resistor Any
103 1 R53 4.7 K, ±1%,R0603 Resistor Any
104 1 R127 470 K, ±1%,R0603 Resistor Any
105 2 C97, C98 47 K, 100 V,C0603 Resistor Any
106 1 R122 47 K, R0805 Resistor Any
AN5237Bill of materials
AN5237 - Rev 1 page 33/45
Item Q.ty Ref. Part/Value Description Manufacturer Order code
107 1 R125 47 K, R0603 Resistor Any
108 1 R120 4k3, R0805 Resistor Any
109 2 R114, R117 4k7, R0805 Resistor Any
110 1 R22 51R1, ±1%,R0805 Resistor Any
111 2 R16, R33 5R6 Resistor Any
112 8R1, R2, R3,R4, R5, R6,R7, R8
75 R, R0603 Resistor Any
113 1 R51 820 R, ±1%,R0603 Resistor Any
114 1 R103 82 k ±1%, R0603 Resistor Any
115 1 R46 91 K ±1%, R0603 Resistor Any
116 2 R67, R118 0 R, R0805 Resistor (notmounted) Any
117 4 R57, R58,R59, R60 0R0, R0805 Resistor (not
mounted) Any
118 1 R132 0R0, R0603 Resistor (notmounted) Any
119 1 R119 100 k, R0603 Resistor (notmounted) Any
120 2 R21, R30 10 K, R0805 Resistor (notmounted) Any
121 1 R54 15 K, R0603, ±1% Resistor (notmounted) Any
122 2 R29, R35 1 K, R0805 Resistor (notmounted) Any
123 2 R17, R34 22 R, R0805 Resistor (notmounted) Any
124 1 R130 2K2, R0603, ±1% Resistor (notmounted) Any
125 1 R23 36R5, ±1%,R0805
Resistor (notmounted) Any
126 1 R27 3Mega, R2010 Resistor (notmounted) Any
127 1 R62 5K6, R0805 Resistor (notmounted) Any
128 1 R129 6K8, ±1% Resistor (notmounted) Any
129 1 R15 R1206 Resistor (notmounted) Any
130 3 R31, R41,R105 R0603 Resistor (not
mounted) Any
131 2 RV1, RV2 1812 Surge arrester(not mounted) TDK B88069X9231T203
132 1 Q7 POWERFLAT_3X3_SGD
SwitchingMOSFET Pchannel
Fairchild-ONSemiconductor FDMC86259P
AN5237Bill of materials
AN5237 - Rev 1 page 34/45
Item Q.ty Ref. Part/Value Description Manufacturer Order code
133 2 Q9, Q12 SOT23_BEC_TSwitchingtransistor NPN(not mounted)
Any
134 2 Q10, Q11 SOT23_BEC_TSwitchingtransistor PNP(not mounted)
Any
135 1 Q3Switchingtransistor NPN(not mounted)
Any MMBT3904LT1
136 4 TP2, TP4,TP6, TP9 Test point black Keystone KEYSTONE_5011
137 14
TP1, TP3,TP5, TP7,TP8, TP12,TP13, TP14,TP15, TP16,TP17, TP18,TP19, TP20
Test point red Keystone KEYSTONE_5010
138 2 TP10, TP11 Test point turret MILLMAX_2501
139 6U5, U10, U16,U17, U18,U19
Diode TVS Transil 1500 W ST SM15T68CA
140 7U6, U7, U8,U9, U11, U20,U21
Diode TVS Transil (notmounted) ST SM15T68CA
141 2 U4, U23 SOT-23-5LEADLow voltageadjustable shuntreference
ST TS431-AILT
142 2 U12, U24 SOT-23-3L
Low voltageadjustable shuntreference (notmounted)
ST TS2431-AILT
143 1 D11 SOT23-D Zener diode (notmounted) Any
AN5237Bill of materials
AN5237 - Rev 1 page 35/45
6 Board layout
Figure 29. STEVAL-POE006V1 PCB top assembly
Figure 30. STEVAL-POE006V1 PCB bottom assembly
AN5237Board layout
AN5237 - Rev 1 page 36/45
Figure 31. STEVAL-POE006V1 PCB layer 1 top
Figure 32. STEVAL-POE006V1 PCB layer 2
AN5237Board layout
AN5237 - Rev 1 page 37/45
Figure 33. STEVAL-POE006V1 PCB layer 3
Figure 34. STEVAL-POE006V1 PCB layer 4
AN5237Board layout
AN5237 - Rev 1 page 38/45
Figure 35. STEVAL-POE006V1 PCB layer 5
Figure 36. STEVAL-POE006V1 PCB layer 6
AN5237Board layout
AN5237 - Rev 1 page 39/45
A ReferencesFreely available on www.st.com:1. PM8804 datasheet2. PM8805 datasheet
AN5237References
AN5237 - Rev 1 page 40/45
Revision history
Table 11. Document revision history
Date Version Changes
20-Dec-2018 1 Initial release.
AN5237
AN5237 - Rev 1 page 41/45
Contents
1 STEVAL-POE006V1 evaluation board overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2
1.1 Specifications, connectors and LEDs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
1.2 Board setup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
2 Configurations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
2.1 PM8805 configurations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.2 PoE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.3 FAUX connector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2.4 RAUX with MPS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2.5 Soft stop . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
3 Measurements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
3.1 Efficiency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
3.2 Output voltage ripple. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
3.3 Input voltage ripple . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
3.4 Startup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
3.5 PoE connector unplugged power off . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
3.6 Primary side waveforms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
3.7 Secondary side waveforms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
3.8 Load transient side waveforms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
3.9 Gloop measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
3.10 Thermal analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
4 STEVAL-POE006V1 schematic diagrams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28
5 Bill of materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30
6 Board layout. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36
A References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .40
Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .41
AN5237Contents
AN5237 - Rev 1 page 42/45
List of figuresFigure 1. STEVAL-POE006V1 evaluation board . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1Figure 2. STEVAL-POE006V1 evaluation board: components view . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4Figure 3. PSE to RAUX switchover at VPSE=55 V, VRAUX=48 V, IOUT=17 A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7Figure 4. RAUX to PSE switchover at VPSE=55 V, VRAUX=48 V, IOUT=17 A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8Figure 5. RAUX to PSE switchover at IOUT=17 A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9Figure 6. STEVAL-POE006V1 overall and DC-DC forward efficiency. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10Figure 7. Output voltage ripple: IOUT= 2 A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11Figure 8. Output voltage ripple: IOUT= 20 A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12Figure 9. Input voltage ripple before and after forward input filter: VIN = 48 V, IOUT =2 A . . . . . . . . . . . . . . . . . . . . . . . 13Figure 10. Input voltage ripple before and after forward input filter: VIN = 48 V, IOUT =20 A. . . . . . . . . . . . . . . . . . . . . . . 14Figure 11. Output voltage at startup: Iout at no load, Vin= 48 V . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15Figure 12. Output voltage at startup: Iout=20 A, Vin= 48 V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16Figure 13. Power off at primary side: Iout=20 A, Vin= 42 V . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17Figure 14. Power off at secondary side (Q1): Iout=20 A, Vin= 42 V . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18Figure 15. Power off at secondary side (Q5): Iout=20 A, Vin= 42 V . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19Figure 16. Primary steady state: Iout=2 A, Vin= 48 V . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20Figure 17. Primary steady state: Iout=20 A, Vin= 48 V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21Figure 18. Secondary steady state: Iout=2 A, Vin= 48 V . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22Figure 19. Secondary steady state: Iout=20 A, Vin= 48 V . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23Figure 20. Load transient: IOUT=10 to 20 A, Vin= 48 V . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24Figure 21. Gloop plot (VIN= 48 V, IOUT=1 A). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25Figure 22. Gloop plot (VIN= 48 V, IOUT=10 A) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25Figure 23. Gloop plot (VIN= 48 V, IOUT=20 A) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25Figure 24. STEVAL-POE006V1 thermography at IOUT=20 A, VIN=41 V . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26Figure 25. STEVAL-POE006V1 thermography at IOUT=20 A, VIN=56 V . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27Figure 26. STEVAL-POE006V1 circuit schematic (1 of 3) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28Figure 27. STEVAL-POE006V1 circuit schematic (2 of 3) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29Figure 28. STEVAL-POE006V1 circuit schematic (3 of 3) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29Figure 29. STEVAL-POE006V1 PCB top assembly. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36Figure 30. STEVAL-POE006V1 PCB bottom assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36Figure 31. STEVAL-POE006V1 PCB layer 1 top . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37Figure 32. STEVAL-POE006V1 PCB layer 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37Figure 33. STEVAL-POE006V1 PCB layer 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38Figure 34. STEVAL-POE006V1 PCB layer 4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38Figure 35. STEVAL-POE006V1 PCB layer 5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39Figure 36. STEVAL-POE006V1 PCB layer 6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
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List of tablesTable 1. STEVAL-POE006V1 specifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2Table 2. STEVAL-POE006V1 connectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2Table 3. STEVAL-POE006V1 LEDs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3Table 4. Tx signal possible configurations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3Table 5. PM8805 control signal description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5Table 6. PM8805 class description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5Table 7. PM8805 PD main parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6Table 8. STEVAL-POE006V1 measurements for IOUT=20 A, VIN=41 V . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26Table 9. STEVAL-POE006V1 measurements for IOUT=20 A, VIN=56 V . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27Table 10. STEVAL-POE006V1 bill of materials. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30Table 11. Document revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
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