EP-86, 6.6W/3.3V/2A PoE PD (EPR-86) Datasheet by Power Integrations

Datasheet Feedback/Errors

gluon-"F IN TEGHA TIONS Summary and Features

Power Integrations

5245 Hellyer Avenue, San Jose, CA 95138 USA.

Tel: +1 408 414 9200 Fax: +1 408 414 9201

www.powerint.com

Title

Engineering Prototype Report for EP-86 –

6.6 W Multi-Class Powered Device (PD) for

Power over Ethernet (PoE) Using

DPA-Switch® (DPA423G)

Specification Input: 33-57 VDC, Output: 3.3 V / 2.0 A

Application PoE Class 2 PD – Including IEEE802.3af

Compliant Interface Circuit

Author Power Integrations Applications Department

Document

Number EPR-86

Date April 13, 2006

Revision 1.1

Summary and Features

• Meets IEEE802.3af requirements according to University of New Hampshire

Interoperability Consortium (UNH-IOC) test results, for Class 1–3 PoE PDs

• DPA-Switch PWM controller with integrated 220 V power MOSFET switch

• Under-voltage (UV) and overvoltage (OV) shutdown functions

• Auto-recovering, hysteretic thermal shutdown

• Auto-restart function: protects against short-circuit and open loop faults

• No-load regulation achieved by cycle skipping

• Fully integrated soft-start minimizes start-up stress and overshoot

• Externally programmed ILIMIT scales with VIN for power limiting

• Lossless MOSFET current sense eliminates external sensing components

• Small footprint 3.1" × 1", low overall height 0.45" (excluding RJ-45 connector)

The products and applications illustrated herein (including circuits external to the products and transformer

construction) may be covered by one or more U.S. and foreign patents or potentially by pending U.S. and foreign

patent applications assigned to Power Integrations. A complete list of Power Integrations’ patents may be found at

www.powerint.com.

EP-86 – 6.6 W, 3.3 V, 2 A PoE Powered Device 13-Apr-2006

Page 2 of 28

Power Integrations

Tel: +1 408 414 9200 Fax: +1 408 414 9201

www.powerint.com

Table Of Contents

1 Introduction.................................................................................................................3

2 Power Supply Specification ........................................................................................4

3 Schematic...................................................................................................................5

4 Circuit Operation.........................................................................................................6

4.1 General ................................................................................................................6

4.2 DPA-Switch Primary.............................................................................................6

4.3 Output Rectification ..............................................................................................6

4.4 Output Feedback..................................................................................................6

4.5 PoE Interface Circuit Description..........................................................................7

4.6 Wide Hysteresis Under-Voltage Lockout..............................................................8

5 Bill of Materials .........................................................................................................10

6 Layout.......................................................................................................................12

7 Transformer Design Spreadsheet.............................................................................13

8 Transformer Specification.........................................................................................15

8.1 Transformer Winding..........................................................................................15

8.2 Electrical Specifications......................................................................................15

8.3 Materials.............................................................................................................15

8.4 Transformer Build Diagram ................................................................................16

8.5 Transformer Construction...................................................................................16

9 Performance Data ....................................................................................................17

9.1 Efficiency............................................................................................................17

9.2 Load Regulation .................................................................................................18

9.3 Line Regulation ..................................................................................................18

9.4 Overload Output Current ....................................................................................19

10 Waveforms............................................................................................................20

10.1 Drain Voltage and Current, Full-Load Operation ................................................20

10.2 Output Voltage Start-Up Profile..........................................................................20

10.3 Load Transient Response (75% to 100% Load Step) ........................................21

10.4 Output Ripple Measurements.............................................................................22

10.4.1 Ripple Measurement Technique ................................................................22

10.4.2 Output Ripple Measurements.....................................................................23

11 Revision History ....................................................................................................24

Important Note:

Although this board was designed to satisfy safety isolation requirements, it has not been

agency approved. Therefore, please take the appropriate safety precautions.

13-Apr-2006 EP-86 – 6.6 W, 3.3 V, 2 A PoE Powered Device

Page 3 of 28

Power Integrations

Tel: +1 408 414 9200 Fax: +1 408 414 9201

www.powerint.com

1 Introduction

This engineering report describes a PoE power supply designed around the DPA423G.

The supply can deliver 6.6 W continuously, from an input voltage range of 33 VDC to

57 VDC.

The following design information is provided: the power supply specification, circuit

diagrams, a complete bill of materials, the results of the PIXls spreadsheet file that was

used to design the supply and detailed information on the design and construction of the

transformer. Data and test results that document the performance of the supply under

various line and load conditions are also included.

Figure 1 – Populated Circuit Board Top View.

Figure 2 – Populated Circuit Board Bottom View.

Description Symbol Min Typ Max Uniis Commem VIN uv oFF Poul FAULT c

EP-86 – 6.6 W, 3.3 V, 2 A PoE Powered Device 13-Apr-2006

Page 4 of 28

Power Integrations

Tel: +1 408 414 9200 Fax: +1 408 414 9201

www.powerint.com

2 Power Supply Specification

Description Symbol Min Typ Max Units Comment

Input

Voltage VIN 33 48 57 VDC

Under-Voltage ON VIN_UV_ON 42 VDC

Under-Voltage OFF VIN_UV_OFF 33 VDC

Output

Output Voltage 1 VOUT1 3.135 3.3 3.465 V ± 5%

Output Ripple Voltage 1 VRIPPLE1 35 mVp-p 20 MHz bandwidth

Output Current 1 IOUT1 0 2 A

Output Peak Current 1 IOUT1_PK 2.5 A

Total Output Power

Average Output Power POUT1 6.6 W

Average Output Power POUT_FAULT 8.6 W R6 = 10.2 Ω

Full Load Efficiency η 73 %

Environmental

Conducted EMI Meets CISPR22B / EN55022B

Safety

Designed to meet IEC950, UL1950

Class II

Ambient Temperature TAMB 0 40

3 Z, x. H 1 u; N E 9 w w A; 1 n a a _ a m m a z 8 s «3% an L x m W En m [j _ In 1 . , 0 V _\‘ ‘ “a, s: a... s m 1 23 2:5 1 a sea 8 33% a a. 5 >3" :2 iii: La «2% E a :2 MW a: «2.3 :9 a 2) 5 z»: a} _ E .2 3 2.. m3 E «awn a . H H E H e Lxﬁm H H g H m E 1 N in." > r ; >9 m <_ sela="" .29355="" .2="" 1%.="" :m="" ,="" 32="" 2::="" 55:3="" 8="" :1...="" eu="" 8="" z="" “se—w="" s,="" ,2:="" e="" as...="" 3="">

13-Apr-2006 EP-86 – 6.6 W, 3.3 V, 2 A PoE Powered Device

Page 5 of 28

Power Integrations

Tel: +1 408 414 9200 Fax: +1 408 414 9201

www.powerint.com

3 Schematic

Figure 3 – Schematic.

EP-86 – 6.6 W, 3.3 V, 2 A PoE Powered Device 13-Apr-2006

Page 6 of 28

Power Integrations

Tel: +1 408 414 9200 Fax: +1 408 414 9201

www.powerint.com

4 Circuit Operation

4.1 General

A flyback topology was used to minimize circuit board size, parts count and cost. This

topology also provides excellent operating efficiency across the input voltage range.

4.2 DPA-Switch Primary

The DPA423G IC implements PWM control of the internal power MOSFET and initiates a

soft start-up function when it first powers up. The IC also monitors die temperature as

part of its over-temperature protection function and also monitors the input voltage as

part of its under-voltage detection and overvoltage shutdown functions. The integrated

220 V MOSFET provides excellent switching characteristics at the selected 400 kHz

operating frequency. The MOSFET and controller consume very little power, giving good

efficiency across the entire input voltage operating range.

Diodes D3 through D9 ensure that the incoming DC input voltage is correctly polarized.

Capacitors C1 and C2 and inductor L1 form a low-cost pi (π) filter that attenuates

conducted EMI noise, to keep it from being passed to the incoming line.

Resistors R4 and R6 program the internal current limit of the DPA423G, so that it

reduces as the input voltage increases. This helps to keep the variance of the maximum

output overload current below 5%, across the entire input voltage range.

The IC’s integrated MOSFET is protected from overvoltage stresses that could damage it

(during a line surge) by a primary-side Zener diode clamp (VR3). Zener diode VR3 does

not conduct under normal operating conditions.

The primary bias winding provides CONTROL pin current after start-up. Diode D2

rectifies the bias winding voltage, while R8 and C11 attenuate high frequency switching

noise and reduce the peak charging of the bias voltage.

4.3 Output Rectification

The secondary winding voltage is rectified by a low-loss Schottky diode (D11). Low ESR,

tantalum output capacitors, C7 and C8, filter the output voltage. The LC output filter (L2,

C9 and C10) further attenuates switching noise and ripple from the output voltage.

4.4 Output Feedback

Resistor divider (R12 and R13) senses the output voltage and feeds it into the reference

pin of a 1.24 V reference IC (U4). The conduction of U4 pulls current through the LED of

optocoupler U5, which controls the conduction of its phototransistor (U5-B).

The phototransistor modulates the current that flows into the CONTROL pin of U1. Since

the DPA-Switch is a current-to-duty-cycle converter, it uses the varying CONTROL pin

current to pulse-width modulate the duty cycle of the MOSFET switch. Resistor R10 sets

the gain of U4, while R11 and C13 compensate for the variation in gain of U4 over the

frequency range of the feedback loop’s bandwidth (about 10 kHz). Feedback

0.80 0.60 Current (mA) .0 ‘6 020 0.00 cwass‘ C‘assz 05533 - - - - DeldeIn - Detect Max 2315 kg ”494mm! I 7 Daecuon Voltage Range 26.5 ksz 0 2 4 6 S 10 12 Voltage (V)

13-Apr-2006 EP-86 – 6.6 W, 3.3 V, 2 A PoE Powered Device

Page 7 of 28

Power Integrations

Tel: +1 408 414 9200 Fax: +1 408 414 9201

www.powerint.com

compensation is required to ensure stable operation of the supply and optimum response

to line and load transients. Capacitor C12 performs a soft-finish function that prevents

the output voltage from overshooting the regulation set point during initial startup of the

converter.

4.5 PoE Interface Circuit Description

See DI-88 for a full description. Resistor R26 provides the correct impedance for the

detection phase of PD operation.

Figure 4 – Detection Impedance V-I curve.

The classification circuit is enabled when Zener diode VR6 conducts (above 11 VDC).

Transistor Q9 controls the bias current source programmed to approximately 350 µA by

resistor R21. This bias current source provides the minimum operating current to voltage

reference IC U6. The main classification current flowing through R20 generates a

voltage that is referenced to the internal reference (1.24 VDC) of U6 and that later closes

the loop by controlling the base drive of Q7. The value of the classification current

source is determined by the value of the voltage on the reference pin of U6 divided by the

value of R20 in ohms.

W W mA mA Ohms 0 0.44 12195 0.5 4 - 1 0,44 3,84 9 12 133 2 3.84 6.49 17 20 69.8 3 649 12.95 26 30 45 3 1 I g C‘assz ; 30 1 was” elasswax E C‘assmcanon 3 33:2? 5' 26 CIassSMln § 5 22 ° E‘Pffzﬂi‘. us I/ 'c'ra'sgz'w 14 IO 12 14 16 18 20 22 Voltage (V)

EP-86 – 6.6 W, 3.3 V, 2 A PoE Powered Device 13-Apr-2006

Page 8 of 28

Power Integrations

Tel: +1 408 414 9200 Fax: +1 408 414 9201

www.powerint.com

Figure 5 – Table of PoE Classifications and Power Levels.

Figure 6 – Classification Current (Class 2: R34 = 69.8 Ω; Class 3: R34 = 45.3 Ω).

Zener diode VR5 conducts above 27 VDC, raising the gate voltage on the pass-switch

MOSFET (Q8), turning it on when the gate-threshold voltage is exceeded. Pull-down

resistor R25 limits the current through VR5 while pull-down resistor R24 keeps Q8 turned

off, unless it is being actively driven on. Zener diode VR4 limits the maximum gate-to-

source voltage on Q8 to 15 V. When VR5 conducts, it also turns on Q6 through R23.

Transistor Q6 pulls down on the base of Q7, which turns off the main classification

current source (although the bias current source of 350 µA will continue to conduct).

4.6 Wide Hysteresis Under-Voltage Lockout

If there were no other components connected to the L pin, then resistor R5 would set the

under-voltage turn-on threshold to approximately 35 VDC and the turn-off threshold to

approximately 33 VDC.

However, in the case of PoE, the turn-on voltage is much higher than the turn-off voltage.

This requires more under-voltage hysteresis. When the power supply is operating

normally, the bias voltage is approximately 14 VDC. Resistors R15 and R16 form a

voltage divider that turns off the base of Q2, once the DC-DC converter has begun

switching and the bias voltage is present. At start-up, when the bias voltage is absent,

ON ‘qum ‘avIom I I Dehuli DPANSWIIEI' OFF 0 so 75 100 y 150 Il I 131 pA 1 1 (35 IIA I I I I ON ‘ ‘ I I , no HA I I I—> I I I DPAMMh I wllh added I uv Hysleleula I I on: 0 25 50) 75 100 125 150 ll 5“ I“ FHCM9DSEDE L Current (uA)

13-Apr-2006 EP-86 – 6.6 W, 3.3 V, 2 A PoE Powered Device

Page 9 of 28

Power Integrations

Tel: +1 408 414 9200 Fax: +1 408 414 9201

www.powerint.com

Q2 is on, and sinks additional current from the resistor (R5) that connects the L pin to the

DC input voltage. The value of R14 was selected so that an extra 10 µA is drawn at

startup, which increases the turn-on threshold voltage to 41 VDC typical. However,

because Q2 turns off after start-up, the UV turn-off threshold stays at 34 VDC (see DI-

101 for more details).

Figure 7 – L-pin current without and with the widened UV hysteresis circuit.

C7, C8, ()9

EP-86 – 6.6 W, 3.3 V, 2 A PoE Powered Device 13-Apr-2006

Page 10 of 28

Power Integrations

Tel: +1 408 414 9200 Fax: +1 408 414 9201

www.powerint.com

5 Bill of Materials

Item Qty. Ref. Description Mfg Part Number Mfg

1 2 C1, C2 470 nF, 100 V, Ceramic, X7R, 1210 ECJ-4YB2A474K Panasonic

2 1 C3 47 pF, 100 V, Ceramic, NPO, 0603 06031A470JAT2A AVX

3 1 C4 1000 pF, 1500V, 1808 1808SC102KAT1A AVX

4 2 C5, C13 100 nF 25 V, Ceramic, X7R, 0603 ECJ-1VB1E104K Panasonic

5 1 C6 22 µF, 10 V, Tant Electrolytic, SMD TAJA226K010R Kemet

6 3 C7, C8, C9 330 µF, 6.3 V, Tant Electrolytic, SMD T495X337K006AS Kemet

7 1 C10 1 µF, 16 V, Ceramic, X5R, 0603

GRM188R61C105KA

93D Murata

8 1 C11 1 µF, 25 V, Ceramic, X7R, 1206 ECJ-3YB1E105K Panasonic

9 1 C12 220 nF, 25 V, Ceramic, X7R, 0603 06033D224KAT2A AVX

10 1 D2

75 V, 0.2 A, Fast Switching, 50 ns, SOD-

323 1N4148WS-7 Diode Inc.

11 8

D3, D4,

D5, D6,

D7, D8,

D9, D10

100 V, 1 A, Rectifier, Glass Passivated, DO-

213AA (MELF) DL4002 Diodes Inc

12 1 D11 20 V, 4 A, Schottky, SMD, DO-214AB SL42-9B Vishay

13 1 J1 R/A, RJ45 Non-shielded, PCBM RJHS-5080 Amphenol Canada

14 2 J2-1, J2-2 Zierick output pins Zierick

15 1 L1 10 µH, 0.85 A HM79-10100LFTR7 B.I.Technologies

16 1 L2 1 µH, 1.9 A HM79-101R0LFTR7 B.I.Technologies

17 1 Q2

PNP, Small Signal BJT, 40 V, 0.2 A, SOT-

323 MMST3906-7 Diodes Inc

18 3

Q4, Q5,

NPN, Small Signal BJT, 80 V, 0.5 A, SOT-

23 MMBTA06LT1 On Semiconductor

19 1 Q6

NPN, Small Signal BJT, 40 V, 0.2 A, SOT-

323 MMST3904 Diodes Inc

20 1 Q8 100 V, 1.15 A, 250 mΩ, N-Channel, SOT-23 SI2328DS Vishay

21 1 R4 1.00 MΩ, 1%, 1/16 W, Metal Film, 0603 ERJ-3EKF1004V Panasonic

22 1 R5 649 kΩ, 1%, 1/8 W, Metal Film, 0805 ERJ-6ENF6493V Panasonic

23 1 R6 10.00 kΩ, 1%, 1/16 W, Metal Film, 0603 ERJ-3EKF1002V Panasonic

24 1 R7 10 Ω, 5%, 1/10 W, Metal Film, 0603 ERJ-3GEYJ100V Panasonic

25 1 R8 100 Ω, 1%, 1/16 W, Metal Film, 0603 ERJ-3EKF1000V Panasonic

26 1 R9 5.1 Ω, 5%, 1/10 W, Metal Film, 0603 ERJ-3GEYJ5R1V Panasonic

27 1 R10 75 Ω, 5%, 1/10 W, Metal Film, 0603 ERJ-3GEYJ750V Panasonic

28 1 R11 1 kΩ, 5%, 1/10 W, Metal Film, 0603 ERJ-3GEYJ102V Panasonic

29 1 R12 33.2 kΩ, 1%, 1/8 W, Metal Film, 0805 ERJ-6ENF3322V Panasonic

13-Apr-2006 EP-86 – 6.6 W, 3.3 V, 2 A PoE Powered Device

Page 11 of 28

Power Integrations

Tel: +1 408 414 9200 Fax: +1 408 414 9201

www.powerint.com

30 1 R13 20 kΩ, 5%, 1/10 W, Metal Film, 0603 ERJ-3GEYJ203V Panasonic

31 1 R14 174 kΩ, 1%, 1/16 W, Metal Film, 0603 ERJ-3EKF1743V Panasonic

32 1 R15, R16 10 kΩ, 5%, 1/10 W, Metal Film, 0603 ERJ-3GEYJ103V Panasonic

35 1 R20 69.8 Ω, 1%, 1/16 W, Metal Film, 0603 ERJ-3EKF69R8V Panasonic

36 1 R21 2 kΩ, 5%, 1/10 W, Metal Film, 0603 ERJ-3GEYJ202V Panasonic

37 2 R22, R23 100 kΩ, 5%, 1/10 W, Metal Film, 0603 ERJ-3GEYJ104V Panasonic

38 1 R24 220 kΩ, 5%, 1/10 W, Metal Film, 0603 ERJ-3GEYJ224V Panasonic

39 1 R25 51 kΩ, 5%, 1/10 W, Metal Film, 0603 ERJ-3GEYJ513V Panasonic

40 1 R26 24.9 kΩ, 1%, 1/8 W, Metal Film, 0805 ERJ-6ENF2492V Panasonic

41 1 T1

Bobbin, ER14.5/6, Horizontal, 10 pins, SMD

HM00-A5861LF

DA2062-ALD

SIL6029

LSTA30825

SNX1393

YC-1404S

B.I Technologies

Coilcraft

Hical

LiShin

Santronics

Ying Chin

42 1 U1 DPA-Switch, DPA423G, SMD-8 DPA423G Power Integrations

43 1 U4

1.24 V Shunt Regulator IC, 1%, -40 to

85 °C, SOT23-5 LMV431AIM5

National

Semiconductor

44 1 U5

Optocoupler, 80 V, CTR 200-400%, 4-Mini

Flat PC357N3T Sharp

45 1 U6

1.24 V Shunt Regulator IC, 1%, -40 to

85 °C, SOT23-5 LMV431AIM5

National

Semiconductor

46 1 VR3 150 V, 5 W, 5%, DO214AC (SMB) SMBJ150A Diodes, Inc

47 1 VR4 15.0 V, 5%, 150 mW, SOD-323 BZT52C15T-7 Diodes, Inc

48 1 VR5 27.0 V, 5%, 150 mW, SOD-323 MAZS2700ML Panasonic-SSG

49 1 VR6 11 V, 5%, 500 mW, DO-213AA (MELF) ZMM5241B-7 Diodes Inc

50 1 - PCB, EP-86, REV B

n J _ _ _ _ _ L

EP-86 – 6.6 W, 3.3 V, 2 A PoE Powered Device 13-Apr-2006

Page 12 of 28

Power Integrations

Tel: +1 408 414 9200 Fax: +1 408 414 9201

www.powerint.com

6 Layout

Figure 8 – PCB Layout Top Side. Figure 9 – PCB Layout Bottom Side.

13-Apr-2006 EP-86 – 6.6 W, 3.3 V, 2 A PoE Powered Device

Page 13 of 28

Power Integrations

Tel: +1 408 414 9200 Fax: +1 408 414 9201

www.powerint.com

7 Transformer Design Spreadsheet

DCDC_DPASwitch_Flyback_071405; Rev.2.7;

DPASwitch_Flyback_071405 - Continuous/Discontinuous

ENTER APPLICATION VARIABLES DC-DC Converter

VDCMIN 36 Volts Minimum DC Input Voltage

VDCMAX 57 Volts Maximum DC Input Voltage

VO 3.3 Volts Output Voltage (main)

PO 6.6 Comment Watts

Verify temperature rise for continuous power. P and G

packages may be thermally limited

n 0.8 Efficiency Estimate

Z0.7 Loss Allocation Factor, (0.7 Recommended)

VB 14 Volts Bias Voltage (Recommended between 12V and 18V)

UV AND OV PARAMETERS

min max

VUVOFF 30.0 33.1 Volts Minimum undervoltage On-Off threshold

VUVON 32.2 34.7 Volts Maximum undervoltage Off-On threshold (turn-on)

VOVON 74.9 - Volts Minimum overvoltage Off-On threshold

VOVOFF 94.7 Volts Maximum overvoltage On-Off threshold (turn-off)

RL 619.0 k-Ohms

ENTER DPASWITCH VARIABLES

DPASWITCH DPA423G 16VDC 36 VDC

Chosen Device DPA423G Power O

6W 13W

ILIMITMAX 1.16 1.34 Amps From DPASWITCH Data Sheet

Frequency FEnter 'F' for fS = 400KHz and 'L' for fS = 300KHz

fS 375000 Hertz DPASWITCH Switching Frequency

VOR 38 38 Volts Reflected Output Voltage

KI 0.7 0.7 Current Limit Reduction Factor

ILIMITEXT 0.812 Amps Minimum External Current limit

RX 11.0 k-Ohms

Resistor from X pin to source to set external current

limit

VDS 1 Volts DPASWITCH on-state Drain to Source Voltage

VD 0.5 Volts Output Winding Diode Forward Voltage Drop

VDB 0.7 Volts Bias Winding Diode Forward Voltage Drop

KRP/KDP 0.62

Ripple to Peak Current Ratio (0.2 < KRP < 1.0 : 1.0<

KDP<6.0)

ENTER TRANSFORMER CORE/CONSTRUCTION VARIABLES

Core Type ER14.5

Core Manuf

Bobbin Manuf

Core ER14.5 P/N: ER14.5-3F3-S

Bobbin ER14.5_Bobbin P/N: CPVS-ER14.5-1S-10P

AE 0.176 cm^2 Core Effective Cross Sectional Area

LE 1.9 cm Core Effective Path Length

AL 1400 nH/T^2 Ungapped Core Effective Inductance

BW 1.9 mm Bobbin Physical Winding Width

M0mm

Safety Margin Width (Half the Primary to Secondary

Creepage Distance)

L 2 Number of Primary Layers

NS 2 Number of Secondary Turns

EP-86 – 6.6 W, 3.3 V, 2 A PoE Powered Device 13-Apr-2006

Page 14 of 28

Power Integrations

Tel: +1 408 414 9200 Fax: +1 408 414 9201

www.powerint.com

CURRENT WAVEFORM SHAPE PARAMETERS

DMAX 0.52 Maximum Duty Cycle

IAVG 0.23 Amps Average Primary Current

IP 0.64 Amps Peak Primary Current

IR 0.40 Amps Primary Ripple Current

IRMS 0.33 Amps Primary RMS Current

TRANSFORMER PRIMARY DESIGN PARAMETERS

LP 119 uHenries Primary Inductance

NP 20 Primary Winding Number of Turns

NB 8 Bias Winding Number of Turns

ALG 297 nH/T^2 Gapped Core Effective Inductance

BP 2739 Gauss

Peak Flux density during transients (Limit to 3000

Gauss)

BM 2152 Gauss Maximum Flux Densit

BAC 667 Gauss

AC Flux Density for Core Loss Curves (0.5 X Peak to

Peak)

ur 1203 Relative Permeability of Ungapped Core

LG 0.06 mm Gap Length (Lg >> 0.051 mm)

BWE 3.8 mm Effective Bobbin Width

TRANSFORMER SECONDARY DESIGN PARAMETERS

ISP 6.38 Amps Peak Secondary Current

ISRMS 3.15 Amps Secondary RMS Current

IO 2.00 Amps Power Supply Output Current

IRIPPLE 2.43 Amps Output Capacitor RMS Ripple Current

VOLTAGE STRESS PARAMETERS

VDRAIN 157 Volts

Maximum Drain Voltage (Includes Effect of Leakage

Inductance)

PIVS 9 Volts Output Rectifier Maximum Peak Inverse Voltage

PIVB 36 Volts Bias Rectifier Maximum Peak Inverse Voltage

ADDITIONAL OUTPUTS

V_OUT2 Volts 2nd Output Voltage

VD_OUT2 Volts 2nd Output - Diode Forward voltage

N_OUT2 0.00 2nd Output - Turns

PIV_OUT2 0 Volts 2nd Output - Diode Peak Inverse Voltage

V_OUT3 Volts 3rd Output Voltage

VD_OUT3 Volts 3rd Output - Diode Forward voltage

N_OUT3 0.00 3rd Output - Turns

PIV_OUT3 0 Volts 3rd Output - Diode Peak Inverse Voltage

I_OUT2 Amps 2nd Output - Output Current

I_OUT3 Amps 3rd Output - Output Current

Negative Output N/A

If negative output exists enter Output number; eg: If

VO2 is negative output, enter 2

13-Apr-2006 EP-86 – 6.6 W, 3.3 V, 2 A PoE Powered Device

Page 15 of 28

Power Integrations

Tel: +1 408 414 9200 Fax: +1 408 414 9201

www.powerint.com

8 Transformer Specification

8.1 Transformer Winding

W3: 2 T

2 x 28 AWG

W4: 10T

1 x 34 AWG

W2: 8T

1 x 34 AWG

9,10

W1: 10T

1 x 34 AWG

6,7

Figure 10 – Transformer Electrical Diagram.

8.2 Electrical Specifications

Electrical Strength 1 second, 60 Hz, from Pins 1-5 to Pins 6-10 1500 VDC

Primary Inductance Pins 1-3, all other windings open 120 µH, ±10%

Resonant Frequency Pins 1-3, all other windings open 7.5 MHz (Min.)

Primary Leakage Inductance Pins 1-3, with Pins 6/7-9/10 shorted 3.0 µH (Max.)

8.3 Materials

Item Description

[1] Core: ER14.5, Ferroxcube 3C96, 3F3 (or equivalent), ALG = 312 nH/T2

[2] Bobbin: ER14.5, 10 pin

[3] Magnet Wire: #34 AWG, Double Coated (Heavy Nyleze)

[4] Magnet Wire: #28 AWG, Double Coated (Heavy Nyleze)

[5] Tape: 3M 1298 Polyester Film (or equivalent), 1.8 mm wide

[6]

(optional) Core Clamp ER14.5 Ferroxcube CLM14.5

[7] Varnish (DIPPED ONLY, NOT VACUUM IMPREGNATED)

EP-86 – 6.6 W, 3.3 V, 2 A PoE Powered Device 13-Apr-2006

Page 16 of 28

Power Integrations

Tel: +1 408 414 9200 Fax: +1 408 414 9201

www.powerint.com

8.4 Transformer Build Diagram

Tape

2 W1

Tape

6,7

Figure 11 – Transformer Build Diagram.

8.5 Transformer Construction

Bobbin Preparation Arrange bobbin & rotation such that primary start/finish wires do not overlap.

W1 Start at Pin 3. Wind 10 turns of item [3] in 1 layer. Bring finish lead back and

terminate on Pin 2.

W2 Starting at Pin 4, wind 8 turns of item [3]. Spread turns evenly across bobbin in

a single layer. Bring finish lead back and terminate on Pin 5.

Tape Use one layer of item [5] for basic insulation.

W3 Start at Pins 9 and 10. Wind 2 turns of bifilar item [4] in 1 layer. Bring finish

lead back and terminate on Pins 6 and 7.

Tape Use one layer of item [5] for basic insulation.

W4 Continue from Pin 2. Wind 10 turns of item [3] in 1 layer. Bring finish lead back

and terminate on Pin 1.

Outer Wrap Use one layer of item [5] for basic insulation.

Final Assembly Assemble and secure (glue or clamp, item [6]) core halves.

Dip varnish item [7] and cure.

13-Apr-2006 EP-86 – 6.6 W, 3.3 V, 2 A PoE Powered Device

Page 17 of 28

Power Integrations

Tel: +1 408 414 9200 Fax: +1 408 414 9201

www.powerint.com

9 Performance Data

All measurements were taken at room temperature utilizing a DC input source and DC

dynamic loads (except where resistive loads are specified). Input and output voltages

and current were measured with dedicated digital multi-meters (DMMs).

9.1 Efficiency

Figure 12 – Efficiency vs. Line and Load, Room Temperature.

40%

50%

60%

70%

80%

02468

Pout (W)

Efficiency (

36 VDC

48 VDC

57 VDC

+ + H

EP-86 – 6.6 W, 3.3 V, 2 A PoE Powered Device 13-Apr-2006

Page 18 of 28

Power Integrations

Tel: +1 408 414 9200 Fax: +1 408 414 9201

www.powerint.com

9.2 Load Regulation

Figure 13 – Load Regulation, Room Temperature.

9.3 Line Regulation

Figure 14 – Line Regulation, Room Temperature.

95.0%

97.5%

100.0%

102.5%

105.0%

02468

Pout (W)

Regulation (%)

3V3 36 VDC

3V3 57 VAC

95.0%

97.5%

100.0%

102.5%

105.0%

30 40 50 60

Vin (VDC)

Regulation (%)

3.3V FL

3.3V LL

13-Apr-2006 EP-86 – 6.6 W, 3.3 V, 2 A PoE Powered Device

Page 19 of 28

Power Integrations

Tel: +1 408 414 9200 Fax: +1 408 414 9201

www.powerint.com

9.4 Overload Output Current

The DC output load current was recorded just prior to the auto-restart operation at

various input line voltages. Performance was measured for various values of resistor R6.

Figure 15 – Overload Output Current vs. Line Voltage for Different Values of R6,

Room Temperature.

0.0

1.0

2.0

3.0

4.0

30 40 50 60

Vin (VDC)

Output Current (A)

3.3 V R6 = 10.0 kΩ

3.3 V R6 = 10.2 kΩ

3.3 V R6 = 10.5 kΩ

3.3 V R6 = 8.66 kΩ

Inns/mm um“) . mus/min: Inns. mum/g mm 3pm., 1 unm47 ; 7 77 7 41.511» . ﬂ LV‘LJLW’L y ‘ l 4 4 ‘ I ‘ y I .‘ > 1‘ 7', ¥ 7 L, , L” 77 ‘ ‘ \ nun/mm) m‘uu mwaml- awn fry/£401 mam mum/s (:23; “mm, ,3 7 7 7 7 77 7 "mm, 1 7,7, 7,, / ‘ ‘

EP-86 – 6.6 W, 3.3 V, 2 A PoE Powered Device 13-Apr-2006

Page 20 of 28

Power Integrations

Tel: +1 408 414 9200 Fax: +1 408 414 9201

www.powerint.com

10 Waveforms

10.1 Drain Voltage and Current, Full-Load Operation

Figure 16 – 36 VDC, Full Load.

Upper: IDRAIN, 0.5 A / div.

Lower: VDRAIN, 50 V, 1 µs / div.

Figure 17 – 57 VDC, Full Load.

Upper: IDRAIN, 0.5 A / div.

Lower: VDRAIN, 50 V, 1 µs / div.

10.2 Output Voltage Start-Up Profile

Figure 18 – Start-Up Profile, 36 VDC, No Load

(worst-case).

Upper: VOUT, 1 V / div.

Lower: VDRAIN, 50 V, 1 µs / div.

Figure 19 – Start-Up Profile, 57 VDC, No Load

(worst-case).

Upper: VOUT, 1 V / div.

Lower: VDRAIN, 50 V, 1 µs / div.

nus/mm mm m1; mus/av mum-v nuns! ‘ 25-4 3 mm Vmemij 7 7 A w ‘ V mm: 7.» nun-v In I: am u... .32 my

13-Apr-2006 EP-86 – 6.6 W, 3.3 V, 2 A PoE Powered Device

Page 21 of 28

Power Integrations

Tel: +1 408 414 9200 Fax: +1 408 414 9201

www.powerint.com

10.3 Load Transient Response (75% to 100% Load Step)

In the figures shown below, signal averaging was used to better enable viewing of the

load transient response. The oscilloscope was triggered using the load current

step as a trigger source. Since the output switching is random with respect

to the load transient, contributions to the output ripple from these sources will

average out, leaving the contribution only from the load step response.

Figure 20 – Transient Response,

36 VDC, 75-100-75% Load Step.

Upper: Load Current, 1 A / div.

Lower: Output Voltage,

20 mV, 500 µs / div.

Figure 21 – Transient Response,

57 VDC, 75-100-75% Load Step.

Upper: Load Current, 1 A / div.

Lower: Output Voltage,

20 mV, 500 µs / div.

EP-86 – 6.6 W, 3.3 V, 2 A PoE Powered Device 13-Apr-2006

Page 22 of 28

Power Integrations, Inc.

Tel: +1 408 414 9200 Fax: +1 408 414 9201

www.powerint.com

10.4 Output Ripple Measurements

10.4.1 Ripple Measurement Technique

For DC output ripple measurements, a modified oscilloscope test probe must be utilized

in order to reduce spurious signal pickup. Details of the probe modification are provided

in Figures 22 and 23.

The 5125BA probe adapter is affixed with two capacitors tied in parallel across the probe

tip. The capacitors include one (1) 0.1 µF/50 V ceramic type and one (1) 1.0 µF/50 V

aluminum electrolytic. Since the aluminum electrolytic type capacitor is polarized,

proper polarity must be observed when connecting it to the output (see below).

Figure 22 – Oscilloscope Probe Prepared for Ripple Measurement (End cap and ground lead removed).

Figure 23 – Oscilloscope Probe with Probe Master 5125BA BNC Adapter (Modified with wires for probe

ground for ripple measurement, and two parallel decoupling capacitors added).

Probe Ground

Probe Tip

manna/m mm: mums/s “In/aw mas/mm mm! mas/s Slur/av Md 2 {anal v: Hume, was/M r j "um! p.4- 7:. ma mu 2 am Ma. —74 my mm v-a 25 mm Inn 2 um n... 72: nut wan/av ‘ nan/m ‘ rum/Inna um... flogwi a 1

EP-86 – 6.6 W, 3.3 V, 2 A PoE Powered Device 13-Apr-2006

Page 23 of 28

Power Integrations

Tel: +1 408 414 9200 Fax: +1 408 414 9201

www.powerint.com

10.4.2 Output Ripple Measurements

Figure 24 – Ripple, 36 VDC, Full Load.

Upper: 50 µs / div, 10 mV / div.

Lower: 2 µs / div, 10 mV / div.

Figure 25 – Ripple, 48 VDC, Full Load.

Upper: 50 µs / div, 10 mV / div.

Lower: 2 µs / div, 10 mV / div.

Figure 26 – Ripple, 57 VDC, Full Load.

Upper: 50 µs / div, 10 mV / div.

Lower: 2 µs / div, 10 mV / div.

EP-86 – 6.6 W, 3.3 V, 2 A PoE Powered Device 13-Apr-2006

Page 24 of 28

Power Integrations, Inc.

Tel: +1 408 414 9200 Fax: +1 408 414 9201

www.powerint.com

11 Revision History

Date Author Revision Description & changes

January 3, 2006 RM/LN/ME 1.0 Initial release

April 13 2006 RM 1.1 Updated photo, layout,

schematic and BOM

EP-86 – 6.6 W, 3.3 V, 2 A PoE Powered Device 13-Apr-2006

Page 25 of 28

Power Integrations

Tel: +1 408 414 9200 Fax: +1 408 414 9201

www.powerint.com

Notes

EP-86 – 6.6 W, 3.3 V, 2 A PoE Powered Device 13-Apr-2006

Page 26 of 28

Power Integrations, Inc.

Tel: +1 408 414 9200 Fax: +1 408 414 9201

www.powerint.com

Notes

EP-86 – 6.6 W, 3.3 V, 2 A PoE Powered Device 13-Apr-2006

Page 27 of 28

Power Integrations

Tel: +1 408 414 9200 Fax: +1 408 414 9201

www.powerint.com

Notes

EP-86 – 6.6 W, 3.3 V, 2 A PoE Powered Device 13-Apr-2006

Page 28 of 28

Power Integrations, Inc.

Tel: +1 408 414 9200 Fax: +1 408 414 9201

www.powerint.com

For the latest updates, visit our website: www.powerint.com

Power Integrations reserves the right to make changes to its products at any time to improve reliability or manufacturability. Power

Integrations does not assume any liability arising from the use of any device or circuit described herein. POWER INTEGRATIONS

MAKES NO WARRANTY HEREIN AND SPECIFICALLY DISCLAIMS ALL WARRANTIES INCLUDING, WITHOUT

LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, AND

NON-INFRINGEMENT OF THIRD PARTY RIGHTS.

PATENT INFORMATION

The products and applications illustrated herein (including transformer construction and circuits external to the products) may be

covered by one or more U.S. and foreign patents, or potentially by pending U.S. and foreign patent applications assigned to Power

Integrations. A complete list of Power Integrations’ patents may be found at www.powerint.com. Power Integrations grants its

customers a license under certain patent rights as set forth at http://www.powerint.com/ip.htm.

The PI Logo, TOPSwitch, TinySwitch, LinkSwitch, DPA-Switch, PeakSwitch, EcoSmart, Clampless, E-Shield,

Filterfuse, PI Expert and PI FACTS are trademarks of Power Integrations, Inc. Other trademarks are property of their respective

Power Integrations Worldwide Sales Support Locations

WORLD HEADQUARTERS

5245 Hellyer Avenue

San Jose, CA 95138, USA.

Main: +1-408-414-9200

Customer Service:

Phone: +1-408-414-9665

Fax: +1-408-414-9765

e-mail: usasales@powerint.com

GERMANY

Rueckertstrasse 3

D-80336, Munich

Germany

Phone: +49-89-5527-3910

Fax: +49-89-5527-3920

e-mail: eurosales@powerint.com

JAPAN

Keihin Tatemono 1st Bldg

2-12-20

Shin-Yokohama, Kohoku-ku,

Yokohama-shi, Kanagawa ken,

Japan 222-0033

Phone: +81-45-471-1021

Fax: +81-45-471-3717

e-mail:

japansales@powerint.com

TAIWAN

5F, No. 318, Nei Hu Rd., Sec. 1

Nei Hu Dist.

Taipei, Taiwan 114, R.O.C.

Phone: +886-2-2659-4570

Fax: +886-2-2659-4550

e-mail:

taiwansales@powerint.com

CHINA (SHANGHAI)

Rm 807-808A,

Pacheer Commercial Centre,

555 Nanjing Rd. West

Shanghai, P.R.C. 200041

Phone: +86-21-6215-5548

Fax: +86-21-6215-2468

e-mail: chinasales@powerint.com

INDIA

261/A, Ground Floor

7th Main, 17th Cross,

Sadashivanagar

Bangalore, India 560080

Phone: +91-80-5113-8020

Fax: +91-80-5113-8023

e-mail: indiasales@powerint.com

KOREA

RM 602, 6FL

Korea City Air Terminal B/D,

159-6

Samsung-Dong, Kangnam-Gu,

Seoul, 135-728, Korea

Phone: +82-2-2016-6610

Fax: +82-2-2016-6630

e-mail:

koreasales@powerint.com

EUROPE HQ

1st Floor, St. James’s House

East Street, Farnham

Surrey, GU9 7TJ

United Kingdom

Phone: +44 (0) 1252-730-140

Fax: +44 (0) 1252-727-689

e-mail: eurosales@powerint.com

CHINA (SHENZHEN)

Room 2206-2207, Block A,

Elec. Sci. Tech. Bldg.

2070 Shennan Zhong Rd.

Shenzhen, Guangdong,

China, 518031

Phone: +86-755-8379-3243

Fax: +86-755-8379-5828

e-mail: chinasales@powerint.com

ITALY

Via Vittorio Veneto 12

20091 Bresso MI

Italy

Phone: +39-028-928-6000

Fax: +39-028-928-6009

e-mail: eurosales@powerint.com

SINGAPORE

51 Newton Road,

#15-08/10 Goldhill Plaza,

Singapore, 308900

Phone: +65-6358-2160

Fax: +65-6358-2015

e-mail:

singaporesales@powerint.com

APPLICATIONS HOTLINE

World Wide +1-408-414-9660

APPLICATIONS FAX

World Wide +1-408-414-9760

EP-86, 6.6W/3.3V/2A PoE PD (EPR-86) Datasheet by Power Integrations

INFORMATION

HELP

CONTACT US

FOLLOW US