Design Example Report

10W Compact Power Supply using

Title
TOP245R
Input: 90 – 300 VAC
Specification
Output: 6V / 1.67A
Application Water Purifier
Author Power Integrations Applications Department
Document
DER-107
Number
Date October 26, 2005
Revision 1.0

Summary and Features

• 66kHz operation to reduce switching losses in TOPSwitch-GX, reduce standby

power consumption and reduce burden on input EMI Filter
• Low profile EFD20 ESHEILD transformer construction
• Simple input π-filter
• No Y-cap No X-cap
• 450 VDC input capacitors for increased reliability for continuous 300 VRMS
operation
• No heat sink design - D2PAK TOPSwitch-GX and D-PAK output rectifier
• 10 W (continuous) / 18 W (peak) in 1.6 X 2.5 X 1”

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.

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Table Of Contents
1 Introduction................................................................................................................. 3
2 Power Supply Specification ........................................................................................ 4
3 Schematic................................................................................................................... 5
4 Circuit Description ...................................................................................................... 6
4.1 Input EMI Filtering ............................................................................................... 6
4.2 TOPSwitch Primary ............................................................................................. 6
4.3 Output Rectification ............................................................................................. 6
4.4 Output Feedback................................................................................................. 6
5 PCB Layout ................................................................................................................ 7
6 Bill Of Materials .......................................................................................................... 8
7 Transformer Specification........................................................................................... 9
7.1 Electrical Diagram ............................................................................................... 9
7.2 Electrical Specifications....................................................................................... 9
7.3 Materials.............................................................................................................. 9
7.4 Transformer Build Diagram ............................................................................... 10
7.5 Transformer Construction.................................................................................. 10
8 PIXL Transformer Spreadsheet................................................................................ 11
9 Performance Data .................................................................................................... 15
9.1 Efficiency........................................................................................................... 15
9.2 No-load Input Power.......................................................................................... 15
9.3 Regulation ......................................................................................................... 16
9.3.1 Load ........................................................................................................... 16
9.3.2 Line ............................................................................................................ 16
10 Waveforms............................................................................................................ 17
10.1 Drain Voltage and Current, Normal Operation .................................................. 17
10.2 Output Voltage Start-up Profile at Full Load...................................................... 17
10.3 Drain Voltage and Current Start-up Profile........................................................ 18
10.4 Load Transient Response (Load Step).............................................................. 19
10.5 Output Ripple Measurements............................................................................ 20
10.5.1 Ripple Measurement Technique ................................................................ 20
10.5.2 Measurement Results ................................................................................ 21
11 Control Loop Measurements................................................................................. 22
11.1 120 VAC Maximum and 3A Load ...................................................................... 22
11.2 240 VAC Maximum and 3A Load ...................................................................... 23
12 Conducted EMI ..................................................................................................... 24
13 Revision History .................................................................................................... 25

Important Notes:
Although this board is designed to satisfy safety isolation requirements, the engineering prototype has not
been agency approved. Therefore, all testing should be performed using an isolated source to provide
power to the prototype board.

Design Reports contain a power supply design specification, schematic, bill of materials, and transformer
documentation. Performance data and typical operation characteristics are included. Typically only a
single prototype has been built.

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DER-107 10 W Compact Power Supply October 26, 2005

1 Introduction

This document is an engineering report describing a universal input 6 V / 10 W power

supply utilizing a TOP245R. This power supply is intended to be used in a compact
adapter for a water purification application. This supply has been design to operate at
300 VAC input continuously as well as provide a peak output current of 3 A for two
minutes.

The document contains the power supply specification, schematic, bill-of-materials,

transformer documentation, printed circuit layout, and performance data.

Top

Bottom

Figure 1 – Populated Circuit Board Photograph

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2 Power Supply Specification

Description Symbol Min Typ Max Units Comment

Input
Voltage VIN 90 300 VAC 2 Wire – no P.E.
Frequency fLINE 47 50/60 64 Hz
No-load Input Power (240 VAC) 0.5 W
Output
Output Voltage 1 VOUT1 6 V ± 5%
Output Ripple Voltage 1 VRIPPLE1 100 mV 20 MHz bandwidth
Output Current 1 IOUT1 1.67 A
Total Output Power
Continuous Output Power POUT 10 W
Peak Output Power POUT_PEAK 18 W 2 minute duration
Efficiency η 75 % Measured at POUT (10 W), 25 oC
Environmental
Conducted EMI Meets CISPR22B / EN55022B
Designed to meet IEC950, UL1950
Safety Class II
1.2/50 µs surge, IEC 1000-4-5,
Series Impedance:
Surge 4 kV Differential Mode: 2 Ω
Common Mode: 12 Ω
100 kHz ring wave, 500 A short
Surge 4 kV circuit current, differential and
common mode
o
Ambient Temperature TAMB 0 40 C Free convection, sea level

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3 Schematic

Figure 2 – Schematic

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4 Circuit Description
The schematic in Figure 2 shows an off-line Flyback converter using the TOP245R. The
circuit is designed for 90 VAC to 300 VAC input and 6 V, 1.67 A output, with a transient
load requirement of 3 A for 2 minutes in duration.

4.1 Input EMI Filtering

Capacitor C1, C2 and L1 form in input p-filter for differential-mode conducted EMI.
Common-mode conducted EMI is reduced with the ESHIELD winding technique
employed in the transformer construction. A input X-capacitor and a Y-capacitor to bridge
the isolation barrier are not required, due to the ESHIELD transformer construction and
frequency dithering of the TOPSwitch-GX.

4.2 TOPSwitch Primary

Rectifier bridge BR1 and C1, C2 provide a high voltage DC BUS for the primary circuitry.
The DC rail is applied to the primary winding of T2. The other side of the transformer
primary is driven by the integrated MOSFET in U1. Diode D4, R7, R3 and C6 clamp
leakage spikes generated when the MOSFET in U1 switches off. Resistor R8 sets the
low-line turn-on threshold to approximately 69 VAC, and also sets the over-voltage
shutdown level to approximately 320 VAC. R2 sets the U1 current limit to approximately
75% of its nominal value. This limits the output power delivered during fault conditions.
C5 bypasses the U1 CONTROL pin. C4 has 3 functions. It provides the energy required
by U1 during startup, sets the auto-restart frequency during fault conditions, and also acts
to roll off the gain of U1 as a function of frequency. R1 adds a zero to stabilize the power
supply control loop. Diode D3 and C12 provide rectified and filtered bias power for U3
and U1. The Frequency pin (F-pin) of U1 is tied to the Control pin (C-pin) to set the
operating frequency of the U1 to 66kHz.

4.3 Output Rectification

The output of T2 is rectified and filtered by D6, C9, and C10. Inductor L2 and C11 provide
additional high frequency filtering.

4.4 Output Feedback

Resistors R9 and R10 divide down the supply output voltage and apply it to the reference
pin of error amplifier U2. Shunt regulator U2 drives optocoupler U3 through resistor R12
to provide feedback information to the U1 CONTROL pin. The optocoupler output also
provides power to U1 during normal operating conditions.
Components C4, C13, R1, R11, and R12 all play a role in compensating the power
supply control loop. Capacitor C4 rolls off the gain of U1 at relatively low frequency.
Resistor R1 provides a zero to cancel the phase shift of C4. Resistor R12 sets the gain of
the direct signal path from the supply output through U2 and U3. Components C13 and
R11 roll off the gain of U2.

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5 PCB Layout

Figure 3 – Printed Circuit Layout

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6 Bill Of Materials

Item QTY Ref Des Description Value Mfg Mfg Part Number
1 1 BR1 600 V, 1 A, Bridge Rectifier, SMD, DFS DFS06 Vishay DFS06
2 2 C1 C2 22 uF, 450 V, Electrolytic, 105C (16 x 25) 22 uF Nichicon UVZ2W220MHD
3 1 C4 47 uF, 16 V, Electrolytic, Gen. Purpose, (5 x 11) 47 uF United Chemi-Con KME16VB47RM5X11LL
4 2 C5 C13 100 nF, 50 V, Ceramic, X7R 100 nF Panasonic ECU-S1H104KBB
5 1 C6 2.2 nF, 1 kV, Disc Ceramic 2.2 nF NIC Components Corp NCD222K1KVY5F
6 2 C9 C10 560 uF, 25 V, Electrolytic, Very Low ESR, 29 mOhm, (8 x 20) 560 uF Rubycon 1EZLH560K8X20
7 1 C11 100 uF, 10 V, Electrolytic, Low ESR, 500 mOhm, (5 x 11.5) 100 uF United Chemi-Con LXZ10VB101ME11LL
8 1 C12 10 uF, 50 V, Electrolytic, Gen. Purpose, (5 x 11) 10 uF United Chemi-Con KMG50VB10RM5X11LL
9 1 D3 200 V, 300 mA, Fast Switching, DO-35 BAV21 Vishay BAV21
10 1 D4 1000 V, 1 A, Rectifier, Glass Passivated, SMA S1M Vishay S1M
11 1 D6 60 V, 6 A, Schottky, SMD, DPAK 6CWQ06 IR 6CWQ06
12 1 F1 3.15 A, 250V, Slow, TR5 FUSE Wickman 3821315041
13 1 L1 1000 uH, 0.28 A 1mH Tokin SBC3-102-281
14 1 L2 3.3 uH, 5.5 A, 8.5 x 11 mm 3.3uH Toko R622LY-3R3M
15 1 R1 6.8 R, 5%, 0805 6.8
16 1 R2 13.7 k, 1%, 0805 13.7 k
17 1 R3 200 k, 5%, 1 W, Metal Oxide 200 k Yageo RSF200JB-200K
18 1 R7 75 R, 5%, 1/8 W, Metal Film, 0805 75
19 1 R8 2.2 M, 5%, 1/4 W, Carbon Film 2.2 M
20 1 R9 6.65 k, 1%, 1/4 W, Metal Film, 1206 6.65 k
21 1 R10 4.75 k, 1%, 1/4 W, Metal Film, 1206 4.75 k
22 1 R11 3.3 k, 5%, 1/8 W, Metal Film, 0805 3.3 k
23 1 R12 100 R, 1%, 1/8 W, Metal Film, 0805 100
24 1 RV1 300 V, 23 J, 7 mm, RADIAL VARISTOR Littlefuse V300LA4
25 1 T2 Bobbin, EFD20, Horizontal, 8 pins BEFD20_8P/Yih-Hwa Enterprises YW-272-03B
26 1 U1 TOPSwitch-GX, TOP245R, TO-263-7C TOP245R Power Integrations TOP245R
27 1 U2 2.495 V Shunt Regulator IC, 1%, -40 to 85C, SOT23 LM431 National Semiconductor LM431BCM
28 1 U3 Opto coupler, 35 V, CTR 80-160%, 4-DIP PC817A Isocom, Sharp ISP817A, PC817X1

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7 Transformer Specification
7.1 Electrical Diagram

Figure 4 – Transformer Electrical Diagram

7.2 Electrical Specifications

Electrical Strength 1 second, 60 Hz, from Pins 1-4 to Pins 5-8 3000 VAC
Pins 3-4, all other windings open, measured at
Primary Inductance 606 µH, -7/+7%
100 kHz, 0.4 VRMS
Resonant Frequency Pins 3-4, all other windings open 800 kHz (Min.)
Pins 3-4, with Pins 5-8 shorted, measured at
Primary Leakage Inductance 100 µH (Max.)
100 kHz, 0.4 VRMS

7.3 Materials
Item Description
2
[1] Core: EFD20/3F3 AL = 104nH/T
[2] Bobbin: 8-pin
[3] Magnet Wire: #35 AWG Heavy Build
[4] Magnet Wire: #27 AWG Heavy Build
[5] Tape: 3M 3mm wide
[6] Tape, 3M
[7] Tape, 3M
[8] Copper tape 1.5 mil thick X 8mm wide
[9] Varnish

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7.4 Transformer Build Diagram

Figure 5 – Transformer Build Diagram

7.5 Transformer Construction

Bobbin Preparation Align bobbin to have pins 1-4 facing the mandrill
Apply 3 mm wide margin on either side of bobbin with item [5]. Match
Primary Margin
height of primary and bias windings.
Start at Pin 3. Wind 76 turns of item [3] in approximately 2 layers, finish
Primary
on Pin 4.
Basic Insulation Use one layer of item [6] for basic insulation.
Starting at Pin 2, wind 14 turns of item [3] uniformly across bobbin width
Bias Winding
in a single layer. Finish at Pin 1.
Basic Insulation Use one layer of item [6] for basic insulation.
Apply 3 mm wide margin on either side of bobbin with item [5]. Match
Primary Margin
height of balanced shield winding.
Start temporarily on pin 6. Wind 4 turns of quadrifilar item [4] uniformly
Balanced Shield
across the bobbin width in a single layer. Finish on pin 4. Cut start of
Winding
winding at 90-degree bend to center of bobbin window.
Reinforced Use three layers of item [7] for reinforced insulation.
Insulation
Apply 3 mm wide margin on either side of bobbin with item [5]. Match
Secondary Margin
height of secondary winding.
Start at Pin 5. Wind 6 trifilar turns of item [4]. Spread turns evenly across
Secondary Winding
bobbin in a single layer. Finish on Pin 8.
Outer Wrap Wrap windings with 3 layers of tape (item [7]).
Core Preparation Affix cores (item [1]) with tape [5].
Wrap one turn of copper tape [8] around outer core. Ensure copper tape
Outer Belly band makes contact with core halves. Solder wire from pin 2 of bobbin to
copper bellyband.
Final Assembly Wrap three layers of tape [7]. Varnish impregnate (item [9]).

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8 PIXL Transformer Spreadsheet

ACDC_TOPSwitchGX_113004; INPUT INFO OUTPUT UNIT TOP_GX_FX_113004.xls:

Rev.2.2; Copyright Power TOPSwitch-GX/FX
Integrations Inc. 2004 Continuous/Discontinuous
Flyback Transformer Design
Spreadsheet
ENTER APPLICATION VARIABLES
VACMIN 85 Volts
VACMAX 300 Volts Maximum AC Input Voltage
fL 50 Hertz AC Mains Frequency
VO 6 Volts Output Voltage
PO 18 Watts Output Power
n 0.73 Efficiency Estimate
Z 0.5 Loss Allocation Factor
VB 15 Volts Bias Voltage
tC 3 mSeconds Bridge Rectifier Conduction Time
Estimate
CIN 44 uFarads Input Filter Capacitor

ENTER TOPSWITCH-GX VARIABLES

TOP-GX TOP245 Universal 115 Doubled/230V
Chosen Device TOP245 Power 60W 85W
Out
KI 0.8 External Ilimit reduction factor
(KI=1.0 for default ILIMIT, KI
<1.0 for lower ILIMIT)
ILIMITMIN 1.296 Amps Use 1% resistor in setting
external ILIMIT
ILIMITMAX 1.584 Amps Use 1% resistor in setting
external ILIMIT
Frequency (F)=132kHz, h Half (H) frequency option -
(H)=66kHz 66kHz
fS 66000 Hertz TOPSwitch-GX Switching
Frequency: Choose between
132 kHz and 66 kHz
fSmin 61500 Hertz TOPSwitch-GX Minimum
Switching Frequency
fSmax 70500 Hertz TOPSwitch-GX Maximum
Switching Frequency
VOR 82 Volts Reflected Output Voltage
VDS 10 Volts TOPSwitch 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
KP 0.9415 Ripple to Peak Current Ratio
(0.4 < KRP < 1.0 : 1.0<
KDP<6.0)

ENTER TRANSFORMER CORE/CONSTRUCTION VARIABLES

Core Type efd20
Core EFD20 P/N: EFD20-3F3

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Bobbin EFD20_BOBBIN P/N: CSH-EFD20-1S-8P

AE 0.58 0.58 cm^2 Core Effective Cross Sectional
Area
LE 5.7 5.7 cm Core Effective Path Length
AL 1800 1800 nH/T^2 Ungapped Core Effective
Inductance
BW 16.4 16.4 mm Bobbin Physical Winding Width
M 3 mm Safety Margin Width (Half the
Primary to Secondary Creepage
Distance)
L 2 Number of Primary Layers
NS 6 Number of Secondary Turns

DC INPUT VOLTAGE PARAMETERS

VMIN 81 Volts Minimum DC Input Voltage
VMAX 424 Volts Maximum DC Input Voltage

CURRENT WAVEFORM SHAPE PARAMETERS

DMAX 0.54 Maximum Duty Cycle
IAVG 0.30 Amps Average Primary Current
IP 1.07 Amps Peak Primary Current
IR 1.01 Amps Primary Ripple Current
IRMS 0.47 Amps Primary RMS Current
TRANSFORMER PRIMARY DESIGN PARAMETERS
LP 606 uHenries Primary Inductance
NP 76 Primary Winding Number of
Turns
NB 14 Bias Winding Number of Turns
ALG 106 nH/T^2 Gapped Core Effective
Inductance
BM 1480 Gauss Maximum Flux Density at PO,
VMIN (BM<3000)
BP 2187 Gauss Peak Flux Density (BP<4200)
BAC 696 Gauss AC Flux Density for Core Loss
Curves (0.5 X Peak to Peak)
ur 1408 Relative Permeability of
Ungapped Core
LG 0.65 mm Gap Length (Lg > 0.1 mm)
BWE 20.8 mm Effective Bobbin Width
OD 0.27 mm Maximum Primary Wire
Diameter including insulation
INS 0.05 mm Estimated Total Insulation
Thickness (= 2 * film thickness)
DIA 0.22 mm Bare conductor diameter
AWG 32 AWG Primary Wire Gauge (Rounded
to next smaller standard AWG
value)
CM 64 Cmils Bare conductor effective area in
circular mils
CMA Warning 137 Cmils/Amp !!!!!!!!!! INCREASE CMA>200
(increase L(primary layers),decrease
NS, larger Core)

TRANSFORMER SECONDARY DESIGN PARAMETERS (SINGLE OUTPUT EQUIVALENT)

Lumped parameters
ISP 13.52 Amps Peak Secondary Current

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ISRMS 5.48 Amps Secondary RMS Current

IO 3.00 Amps Power Supply Output Current
IRIPPLE 4.59 Amps Output Capacitor RMS Ripple
Current

CMS 1097 Cmils Secondary Bare Conductor

minimum circular mils
AWGS 19 AWG Secondary Wire Gauge
(Rounded up to next larger
standard AWG value)
DIAS 0.91 mm Secondary Minimum Bare
Conductor Diameter
ODS 1.73 mm Secondary Maximum Outside
Diameter for Triple Insulated
Wire
INSS 0.41 mm Maximum Secondary Insulation
Wall Thickness

VOLTAGE STRESS PARAMETERS

VDRAIN 616 Volts Maximum Drain Voltage
Estimate (Includes Effect of
Leakage Inductance)
PIVS 40 Volts Output Rectifier Maximum Peak
Inverse Voltage
PIVB 96 Volts Bias Rectifier Maximum Peak
Inverse Voltage

TRANSFORMER SECONDARY DESIGN PARAMETERS (MULTIPLE OUTPUTS)

1st output
VO1 6.0 6 Volts Output Voltage
IO1 3.000 3 Amps Output DC Current
PO1 18.00 Watts Output Power
VD1 0.5 0.5 Volts Output Diode Forward Voltage
Drop
NS1 6.00 Output Winding Number of Turns
ISRMS1 5.484 Amps Output Winding RMS Current
IRIPPLE1 4.59 Amps Output Capacitor RMS Ripple
Current
PIVS1 40 Volts Output Rectifier Maximum Peak
Inverse Voltage

CMS1 1097 Cmils Output Winding Bare Conductor

minimum circular mils
AWGS1 19 AWG Wire Gauge (Rounded up to next
larger standard AWG value)
DIAS1 0.91 mm Minimum Bare Conductor
Diameter
ODS1 1.73 mm Maximum Outside Diameter for
Triple Insulated Wire

2nd output
VO2 6.0 Volts Output Voltage
IO2 1.670 Amps Output DC Current
PO2 10.02 Watts Output Power
VD2 0.5 Volts Output Diode Forward Voltage
Drop
NS2 6.00 Output Winding Number of Turns

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ISRMS2 3.053 Amps Output Winding RMS Current

IRIPPLE2 2.56 Amps Output Capacitor RMS Ripple
Current
PIVS2 40 Volts Output Rectifier Maximum Peak
Inverse Voltage

CMS2 611 Cmils Output Winding Bare Conductor

minimum circular mils
AWGS2 22 AWG Wire Gauge (Rounded up to next
larger standard AWG value)
DIAS2 0.65 mm Minimum Bare Conductor
Diameter
ODS2 1.73 mm Maximum Outside Diameter for
Triple Insulated Wire

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9 Performance Data
All measurements performed at room temperature, 60 Hz input frequency.

9.1 Efficiency

Figure 6 – Efficiency vs. Input Voltage, Room Temperature, 60 Hz.

9.2 No-load Input Power

Figure 7 – Zero Load Input Power vs. Input Line Voltage, Room Temperature, 60 Hz

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9.3 Regulation

9.3.1 Load

Figure 8 – Load Regulation, Room Temperature

9.3.2 Line

Figure 9 – Line Regulation, Room Temperature, Full Load

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10 Waveforms
10.1 Drain Voltage and Current, Normal Operation

Figure 10 – 90 VAC, Full Load. Figure 11 – 265 VAC, Full Load

Upper: IDRAIN, 0.5 A / div Upper: IDRAIN, 0.5 A / div
Lower: VDRAIN, 100 V, 2 µs / div Lower: VDRAIN, 200 V / div

10.2 Output Voltage Start-up Profile at Full Load

Figure 12 – Start-up Profile, 120VAC Figure 13 – Start-up Profile, 240 VAC

1 V, 2 ms / div. 1 V, 2 ms / div.

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10.3 Drain Voltage and Current Start-up Profile

Figure 14 – 90 VAC Input and Maximum Load. Figure 15 – 265 VAC Input and Maximum Load.
Upper: IDRAIN, 0.5 A / div. Upper: IDRAIN, 0.5 A / div.
Lower: VDRAIN, 100 V & 1 ms / div. Lower: VDRAIN, 200 V & 1 ms / div.

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10.4 Load Transient Response (Load Step)

In the figures shown below, signal averaging was used to better enable viewing the load
transient response. The oscilloscope was triggered using the load current step as a
trigger source. Since the output switching and line frequency occur essentially at 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 16 – Transient Response, 120 VAC, 75-100- Figure 17 – Transient Response, 120 VAC, 100-180-
75% Load Step. 100% Load Step
Bottom: Load Current, 1 A/div. Bottom: Load Current, 1 A/ div.
Top: Output Voltage Top: Output Voltage
2000 mV, 5V offset, 1ms / div. 200 mV 5V offset, 1 ms / div.

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10.5 Output Ripple Measurements

10.5.1 Ripple Measurement Technique

For DC output ripple measurements, a modified oscilloscope test probe must be utilized
in order to reduce spurious signals due to pickup. Details of the probe modification are
provided in Figure 18 and Figure 19.

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. The aluminum electrolytic type capacitor is polarized, so
proper polarity across DC outputs must be maintained (see below).

Probe Ground

Probe Tip

Figure 18 – Oscilloscope Probe Prepared for Ripple Measurement. (End Cap and Ground Lead Removed)

Figure 19 – Oscilloscope Probe with Probe Master 5125BA BNC Adapter. (Modified with wires for probe
ground for ripple measurement, and two parallel decoupling capacitors added)

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10.5.2 Measurement Results

Figure 20 – Ripple, 120VAC, Full Load. Figure 21 – Ripple, 240VAC, Full Load.
2 ms, 20 mV / div 2 ms, 20 mV / div

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11 Control Loop Measurements

11.1 120 VAC Maximum and 3A Load

Figure 22 – Gain-Phase Plot, 120 VAC, Maximum Steady State Load

Vertical Scale: Gain = 8 dB/div, Phase = 40 °/div.
Crossover Frequency = 2.66 kHz Phase Margin = 88.11°

Figure 23 – Gain-Phase Plot, 120 VAC, 3A Load

Vertical Scale: Gain = 12 dB/div, Phase = 40 °/div.
Crossover Frequency = 1.32 kHz Phase Margin = 84.02°

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11.2 240 VAC Maximum and 3A Load

Figure 24 – Gain-Phase Plot, 240 VAC, Maximum Steady State Load

Vertical Scale: Gain = 8 dB/div, Phase = 40 °/div.
Crossover Frequency = 11.11 kHz Phase Margin = 57.14°

Figure 25 – Gain-Phase Plot, 240 VAC, 3A Load

Vertical Scale: Gain = 12 dB/div, Phase = 40 °/div.
Crossover Frequency = 7.26 kHz Phase Margin = 71.65°

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12 Conducted EMI

Figure 26 – Maximum Steady State Load, 120 VAC/ Figure 27 – Maximum Steady State Load, 120VAC/60
60 Hz, and EN55022 B Limits (LINE) Hz, and EN55022 B Limits (Neutral)

Figure 28 – Maximum Steady State Load, 240 Figure 29 – Maximum Steady State Load, 240VAC/60
VAC/ 60 Hz, and EN55022 B Limits (LINE) Hz, and EN55022 B Limits (Neutral)

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DER-107 10 W Compact Power Supply October 26, 2005

13 Revision History

Date Author Revision Description & changes Reviewed

10-26-05 RSP 1.0 Initial Release KM/JC/VC

Power Integrations
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DER-107 10 W Compact Power Supply October 26, 2005

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, EcoSmart, PI Expert and PI FACTS are trademarks
of Power Integrations, Inc. Other trademarks are property of their respective companies. ©Copyright 2005 Power Integrations, Inc.

Power Integrations Worldwide Sales Support Locations

WORLD HEADQUARTERS GERMANY JAPAN TAIWAN
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