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Title Engineering Prototype Report for EP-68 –
6.6 W DC-DC Flyback Converter Using
DPA-Switch™ (DPA423G)
Specification Input: 36-57 VDC, Output: 3.3 V / 2 A
Application Power over Ethernet (PoE) Power Supply
Author Power Integrations Applications Department
Document
Number EPR-68
Date 19-Jul-2005
Revision 1.1
Summary and Features
• High efficiency, low parts count and low cost power supply
• Ideally suited for PoE, VoIP, standby and other distributed 48 V DC-DC
conversion applications
• Signature circuit is fully compatible with IEEE 802.3af requirements
• DPA-Switch Integrates
• PWM controller and 220 V MOSFET switching device
• Accurate input voltage UV detection and OV protection
• Thermal, overload, short-circuit and open loop protection
• Regulation at zero load (cycle skipping)
• Accurate 400 kHz trimmed internal oscillator
• Small footprint 2" × 1", low overall height 0.9", dual layer PCB
• 100% surface mount construction
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.
EP68 3.3 V, 2 A DC-DC Power Supply 19-Jul-2005
Table Of Contents
1 Introduction..................................................................................................................3
2 Power Supply Specification.........................................................................................4
3 Schematic ...................................................................................................................5
4 Circuit Description .......................................................................................................6
4.1 DPA-Switch Primary............................................................................................6
4.2 Output Rectification .............................................................................................6
4.3 Output Feedback.................................................................................................7
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 Transformer Spreadsheet .........................................................................................11
9 Performance Data .....................................................................................................13
9.1 Efficiency ...........................................................................................................13
9.2 Regulation .........................................................................................................14
9.2.1 Load...............................................................................................................14
9.2.2 Line................................................................................................................14
9.3 Peak Power .......................................................................................................15
10 Waveforms ................................................................................................................15
10.1 Drain Voltage and Current, Full Load Operation ...............................................15
10.2 Output Voltage Start-Up Profile .........................................................................16
10.3 Drain Voltage and Current Start-Up Profile .......................................................16
10.4 Load Transient Response (75% to 100% Load Step) .......................................17
10.5 Output Ripple Measurements............................................................................18
10.5.1 Ripple Measurement Technique ....................................................................18
10.5.2 Output Ripple Measurements ........................................................................19
11 Thermal Performance................................................................................................20
12 Control Loop Measurements .....................................................................................22
12.1 36 VDC Maximum and Nominal Load ...............................................................22
12.2 57 VDC Maximum Load ....................................................................................23
13 Revision History ........................................................................................................24
Important Note:
Although this board is designed to satisfy safety telecom isolation requirements, this
engineering prototype has not been agency approved.
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19-Jul-2005 EP68 3.3 V, 2 A DC-DC Power Supply
1 Introduction
This engineering report describes a 3.3 V / 2 A (6.6 W) DC-DC converter that is based on
a DPA423G device. This design is intended as an evaluation platform for DPA-Switch
devices in the low cost surface-mount DIP package. High operating efficiency, low parts
count, small footprint and low height make this an ideal choice for Power over Ethernet
(PoE) and VoIP DC-DC converter applications.
This report contains the power supply specification, schematic, bill of materials,
transformer documentation, printed circuit board layout, and performance data.
Figure 1 - EP68 Populated Circuit Board Photograph.
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EP68 3.3 V, 2 A DC-DC Power Supply 19-Jul-2005
2 Power Supply Specification
Description Symbol Min Typ Max Units Comment
Input
Voltage VIN 36 57 VDC
PoE input range specification
Output
Output Voltage VOUT1 3.20 3.30 3.40 V ±3% including set point and
line/load regulation
Output Ripple Voltage VRIPPLE1 35 50 mVpp 20 MHz bandwidth
Continuous Output Current IOUT 2.0 A
Peak Output Current IOUT 2.5 A
Total Output Po wer
Continuous Output Power POUT 6.6 W
Peak Output Power POUT_PEAK 8.3 W
Efficiency η 77 78 % Measured at 48 V,
POUT (6.6 W), 25 oC
Environmental
Safety Isolation 1500 VDC 1 min.
Ambient Temperature TAMB 0 50
oC Free convection, sea level
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19-Jul-2005 EP68 3.3 V, 2 A DC-DC Power Supply
3 Schematic
*All resistors and capacitors are 0805 size unless otherwise specified
Figure 2 - EP68 Schematic.
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EP68 3.3 V, 2 A DC-DC Power Supply 19-Jul-2005
4 Circuit Description
The Flyback topology was used to minimize circuit board size, parts count and cost, while
attaining excellent operating efficiency across the input voltage range.
4.1 DPA-Switch Primary
The DPA423G IC provides PWM control, startup, feedback, under/over voltage and over-
temperature protection functions. The integrated 220 V MOSFET provides excellent
switching characteristics at the selected 400 kHz operating frequency. The MOSFET and
controller consume minimal power, enabling a typical operating efficiency of 74%-78%
across the operating input voltage range (see Figure 7).
R1 provides a 25 kΩ input impedance, consistent with PoE Class 0 requirements. Above
30 V, Zener VR1 conducts, allowing n-channel MOSFET Q1 to turn on. Zener diode VR2
protects the gate of Q1 from overvoltage damage. Resistors R2 and R3 provide
repeatable on and off timing.
Resistor R5 programs the typical input under-voltage ON threshold to 33 VDC. Resistors
R4 and R6 program the internal device current limit to reduce with increasing input
voltage. Maximum output (overload) current varies less than 5% across the operating
voltage range. The reduction in overload output current reduces secondary transformer
leakage spikes and allows the use of a 30 V Schottky diode, for the output rectifier D1.
The primary-side Zener clamp, VR3, provides protection of the DPA423G drain under
input surge and overvoltage conditions. 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, while components R8 and C11 reduce the high frequency
switching noise and reduce the peak charging of the bias voltage.
The DPA423G operates well within the recommended junction temperature limits
(100 °C) at an elevated ambient of 50 °C, in a free-convection cooled environment (see
Section 11).
4.2 Output Rectification
Schottky output diode D1 enables low-loss rectification of the secondary winding voltage.
Low ESR tantalum output capacitors, C7-9, reduce switching ripple and minimize losses.
Secondary output choke L1 and ceramic output capacitor C10 reduce high frequency
noise and ripple at the output.
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4.3 Output Feedback
The output voltage is sensed via the resistor divider formed by R12 and R13 and fed into
the reference pin of the low voltage reference, U3. Feedback compensation components
R10, R11, and C13 ensure stable operation and optimum line and load transient
response. Capacitor C12 provides a soft-finish characteristic, preventing output voltage
overshoot during startup of the converter.
5 PCB Layout
Figure 3 - Top Side, SMT Printed Circuit Layout (Top View).
Figure 4 - Bottom Side, SMT Printed Circuit Layout (Top View).
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EP68 3.3 V, 2 A DC-DC Power Supply 19-Jul-2005
6 Bill of Materials
Item Qty Reference Description P/N Manufacturer
1 1 U1 DPA-Switch DPA423G Power Integrations
2 1 U2 Optocoupler, 80-160% graded
CTR
PC357N1TA Sharp
3 1 U3 Low voltage shunt regulator,
SOT23
CAT431L Catalyst Semiconductor
4 1 C1, C2 1.5 µF, 100 V, 1812 THCS50E2A155ZT UCC
5 1 C3 47 pF, 200 V ECJ-2VC2D470J Panasonic
6 1 C4 1000 pF, 1500V, 1808 1808SC102KAT1A AVX
7 2 C5, C13 0.1 µF, 50 V ECJ-2YB1H104K Panasonic
8 1 C6 22 µF, 10 V, tantalum, C size ECST1AC226R Panasonic
9 3 C7-9 330 µF, 6.3 V, tantalum, X size T495X337K006AS Kemet
10 1 C10 1 µF, 10 V, 0508 alternative
geometry
ECY-29RA105KV Panasonic
11 1 C11 1 µF, 50 V, 1206 ECJ-3FF1H105Z Panasonic
12 1 C12 0.33 µF, 50 V ECJ-2YB1C334K Panasonic
13 1 D1 30 V, 4 A Schottky SL43 Vishay
14 1 D2 200 V, 200 mA BAV21 generic
15 4 J1-1,2
J2-1,2
Pin, Surface Mount,
0.040 x 0.375”
4531051-0000 Zierick
16 1 L1 10 µH, 1 A SCD-0403-100MT Chilisin
17 1 L2 1 µH, 2 A SCD-0403-1R0M Chilisin
18 1 Q1 MOSFET, N Channel, 100 V,
250 mΩ
Si2328DS-T1 Vishay
19 1 R1 24.9 kΩ, 1%, 1206 ERJ-8ENF2492V Panasonic
20 1 R2 51 kΩ ERJ-6GEYJ513V Panasonic
21 1 R3 249 kΩ ERJ-6GEY2493V Panasonic
22 1 R4 1.00 MΩ, 1% ERJ-6ENF1004V Panasonic
23 1 R5 619 kΩ, 1% ERJ-6ENF6193V Panasonic
24 1 R6 8.66 kΩ, 1% ERJ-6ENF8661V Panasonic
25 1 R7 10 Ω ERJ-6GEYJ100V Panasonic
26 1 R8 100 Ω ERJ-6GEYJ101V Panasonic
27 1 R9 5.1 Ω ERJ-6GEYJ5R1V Panasonic
28 1 R10 75 Ω ERJ-6GEYJ750V Panasonic
29 1 R11 1 kΩ ERJ-6GEYJ102V Panasonic
30 1 R12 34.0 kΩ, 1% ERJ-6ENF3402V Panasonic
31 1 R13 20.0 kΩ, 1% ERJ-6ENF2002V Panasonic
32 1 T1 ER14.5 Transformer LSTA30825
SIL6029
IM 040 202 31
L.S.E.
HiCal
Vogt
33 1 VR1 27V, 500 mW, SOD123 BZT52C27-7 Diodes, Inc. or Generic
34 1 VR2 15V, 200 mW, SOD323 BZT52C15S-7 Diodes, Inc. or Generic
35 1 VR3 150V TVS SMAJ150A Generic
*Resistors and capacitors are size 0805, unless otherwise specified.
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7 Transformer Specification
7.1 Electrical Diagram
WDG #3
2T #28 AWG x2
WDG #1
10T #34 AWG WDG #2
8T #34 AWG
WDG #4
10T #34 AWG
1
2
3
9,10
6,7
4
5
ER14.5 3C96 / 3F3,
10 pin Bobbin
Figure 5 - Transformer Electrical Diagram.
7.2 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.)
7.3 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] Core Clamp ER14.5 Ferroxcube CLM14.5 (optional)
[7] Varnish (DIPPED ONLY, NOT IMPREGNATED)
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EP68 3.3 V, 2 A DC-DC Power Supply 19-Jul-2005
7.4 Transformer Build Diagram
3
4
2
5
1
1/2 Primary
Bias
Secondary
1/2 Primary
Tape
Tape
Pin Side
Tape
6,7
9,10
Figure 6 - Transformer Build Diagram.
7.5 Transformer Construction
Bobbin Preparation Arrange bobbin & rotation such that primary start/finish wires do not
overlap.
½ Primary Start at Pin 3. Wind 10 turns of item [3] in 1 layer. Bring finish lead back
and terminate on Pin 2.
Bias Winding 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.
Basic Insulation Use one layer of item [5] for basic insulation.
Secondary Winding 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.
Basic Insulation Use one layer of item [5] for basic insulation.
½ Primary Continue from Pin 2. Wind 10 turns of item [3] in 1 layer. Bring finish lead
back and terminate on Pin 1.
Outer Insulation 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.
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8 Transformer Spreadsheet
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19-Jul-2005 EP68 3.3 V, 2 A DC-DC Power Supply
9 Performance Data
All measurements were taken at room temperature utilizing a DC input source and
dynamic DC loads. Input and output voltages and output current were measured with
dedicated DVMs.
9.1 Efficiency
Figure 7 - Efficiency vs Output Load, Room Temperature.
Efficiency Vs. Output Load
70%
71%
72%
73%
74%
75%
76%
77%
78%
79%
80%
0.50 0.75 1.00 1.25 1.50 1.75 2.00
Load Current (A)
Efficiency (%)
VIN=36 VDC
VIN=48 VDC
VIN=57 VDC
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EP68 3.3 V, 2 A DC-DC Power Supply 19-Jul-2005
9.2 Regulation
9.2.1 Load
Load Regulation
3.20
3.25
3.30
3.35
3.40
0.0 0.3 0.5 0.8 1.0 1.3 1.5 1.8 2.0
Load Curr ent (A)
Output Voltage (VDC)
VIN=36 VDC
VIN=48 VDC
VIN=57 VDC
Figure 8 - Load Regulation, Room Temperature.
9.2.2 Line
Line Regulation
3.20
3.25
3.30
3.35
3.40
30.0 40.0 50.0 60.0
Input Voltage (VDC)
Output Voltage (VDC)
Full Load (2 A)
50% Load (1 A)
No Load
Figure 9 - Line Regulation, Room Temperature.
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9.3 Peak Power
The DC output load current was recorded just prior to the auto-restart operation.
Maximum Output Current
2.50
2.60
2.70
2.80
2.90
3.00
30.0 40.0 50.0 60.0
Input Vol tage (VDC)
Output Current (A)
Figure 10 - Maximum Output Overload Current, Room Temperature.
10 Waveforms
10.1 Drain Voltage and Current, Full Load Operation
Figure 11 – 36 VDC, Full Load.
Upper: IDRAIN, 0.5 A / div.
Lower: VDRAIN, 50 V, 1 µs / div.
Figure 12 – 57 VDC, Full Load.
Upper: IDRAIN, 0.5 A / div.
Lower: VDRAIN, 50 V, 1 µs / div.
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10.2 Output Voltage Start-Up Profile
Figure 13 - Start-Up Profile, 36 VDC, No Load
(worst-case).
Upper: VOUT, 1 V / div.
Lower: VDRAIN, 50 V, 10 ms / div.
Figure 14 - Start-Up Profile, 57 VDC, No Load
(worst-case).
Upper: VOUT, 1 V / div.
Lower: VDRAIN, 50 V, 10 ms / div.
10.3 Drain Voltage and Current Start-Up Profile
Figure 15 – 36 VDC Input, 2 A Resistive Load.
Upper: IDRAIN, 0.5 A / div.
Lower: VDRAIN, 100 V, 10 ms / div.
Figure 16 – 57 VDC Input, 2 A Resistive Load.
Upper: IDRAIN, 0.5 A / div.
Lower: VDRAIN, 100 V, 10 ms / div.
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10.4 Load Transient Response (75% to 100% Load Step)
In the following two oscilloscope screen shots (Figures 17 and 18), signal averaging was
used to more clearly capture the output voltage response to a load transient. Averaging
minimizes the appearance of the 400 kHz switching ripple in the output voltage scope
plot. The load current step was used to trigger the horizontal sweep of the oscilloscope.
Figure 17 - Transient Response,
36 VDC, 75-100-75% Load Step.
Top: Load Current, 1 A / div.
Bottom: Output Voltage,
20 mV, 500 µs / div.
Figure 18 - Transient Response,
57 VDC, 75-100-75% Load Step.
Top: Load Current, 1 A / div.
Bottom: Output Voltage,
20 mV, 500 µs / 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 Figures 19 and 20.
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 19 - Oscilloscope Probe Prepared for Ripple Measurement (End Cap and Ground Lead Removed).
Figure 20 - 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 Output Ripple Measurements
Figure 21 - Ripple, 36 VDC, Full Load.
Top: 10 mV / div, 50 µs / div.
Bottom: 10 mV / div, 2 µs / div.
Figure 22 - Ripple, 48 VDC, Full Load.
Top: 10 mV / div, 50 µs / div.
Bottom: 10 mV / div, 2 µs / div.
Figure 23 - Ripple, 57 VDC, Full Load.
Top: 10 mV / div, 50 µs / div.
Bottom: 10 mV / div, 2 µs / div.
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11 Thermal Performance
The temperatures of key components were recorded using T-type thermocouples. Two
of the four thermocouples were soldered; one directly to a SOURCE pin of the DPA423G
(U1) and the other to the cathode of the output rectifier (D1). The other two
thermocouples were glued; one to the transformer (T1) core, on the center leg, and the
other to the case of the first (of the two) high-ripple output capacitor (C7).
The unit was operated at full load, at 36 VDC, 48 VDC and 57 VDC, in free convection
within a small enclosure.
The results show adequate thermal margin, considering an additional ambient rise of
+28 °C, equivalent to operating at an ambient of 50 °C. At 36 VDC, full load, within an
enclosure at 50 °C ambient, this equates to a DPA423G case temperature of 79 °C. This
is well below the recommended maximum case temperature of 100 °C.
Figure 24 is an infrared thermograph taken at nominal-line (48 VDC).
Measured Temperature (°C)
Item 36 VDC 48 VDC 57 VDC
Ambient 22 22 22
DPA423G (U1) 51 51 53
Transformer core (T1) 75 75 75
Output Rectifier (D1) 63 61 61
Output Capacitor (C7) 45 43 43
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19-Jul-2005 EP68 3.3 V, 2 A DC-DC Power Supply
TOP VIEW
BOTTOM VIEW
Figure 24- Infrared Thermograph of the EP68 Board, 48 VDC, Full Load, Room Ambient.
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12 Control Loop Measurements
12.1 36 VDC Maximum and Nominal Load
Figure 25 - Gain-Phase Plot, 36 VDC, Maximum Load (2 A).
Vertical Scale: Gain = 10 dB / div, Phase = 30° / div.
Crossover Frequency = 10.0 kHz, Phase Margin = 60°
Figure 26 - Gain-Phase Plot, 36 VDC, Light Load (100 mA).
Vertical Scale: Gain = 10 dB / div, Phase = 30° / div.
Crossover Frequency = 0.9 kHz, Phase Margin = 65°
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12.2 57 VDC Maximum Load
Figure 27 - Gain-Phase Plot, 57 VDC, Light Load (100 mA).
Vertical Scale: Gain = 10 dB / div, Phase = 30° / div.
Crossover Frequency = 10.8 kHz, Phase Margin = 40°
Figure 28 - Gain-Phase Plot, 57 VDC, Light Load (100 mA).
Vertical Scale: Gain = 10 dB / div, Phase = 30° / div.
Crossover Frequency = 0.9 kHz, Phase Margin = 60°
The results indicate adequate loop bandwidth and significant gain and phase margin.
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13 Revision History
Date Author Revision Description & changes
25-Feb-04 SH 0.1 First release
02-Mar-04 PV 0.2 Second release after minor edits
15-Mar-04 PV 1.0 Final release
19-Jul-05 PV 1.1 Fixed schematic and bill of materials (BOM)
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19-Jul-2005 EP68 3.3 V, 2 A DC-DC Power Supply
Notes
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EP68 3.3 V, 2 A DC-DC Power Supply 19-Jul-2005
Notes
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19-Jul-2005 EP68 3.3 V, 2 A DC-DC Power Supply
Notes
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EP68 3.3 V, 2 A DC-DC Power Supply 19-Jul-2005
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Integrations does not assume any liab ility aris ing from the use of any device or circu it described herein. POWER INTEGRA TIONS
MAKES NO WARRANTY HEREIN AND SPECIFICALLY DISCLAIMS ALL WARRANTIES INCLUDING, WITHOUT
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NON-INFRINGEMENT OF THIRD PARTY RIGHTS.
PATENT INFOR MAT ION
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 fo reign patents, or potentially by pending U.S. and foreign patent applications ass igned to Power
Integrations. A complete list of Power Integrations’ patents may be found at www.powerint.com. Power Integrations grants its
custome r s a license under certain pa te nt rights a s set for th at http: //www. pow e ri nt.com/i p. htm.
Th e P I L o g o , TOPSwitch, TinySwitch, LinkSwitch, DPA-Switch, EcoSmart, PI Expert and PI FACTS are trad emarks
o f P ower I nt e gr a ti o ns, I nc. Oth er tr a de mark s are pr ope rt y of their re spec tiv e c omp a ni e s. © C opyright 2005 Power Integ ra ti on s, I nc.
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Ja pan 222 -0033
P ho ne: +81-4 5-471 -1021
Fa x: +81-4 5-471 -37 17
e-mail:
japansales@powerint.com
TAIWAN
5F, No. 318, Nei Hu Rd., Sec. 1
Nei Hu Dis t.
Taipei, Taiwa n 1 14 , R.O.C.
P ho ne: +88 6-2- 265 9-4570
Fa x: +88 6- 2-265 9-4550
e-mail:
taiwansales@powerint.com
CHINA (SHANGHAI)
Rm 807-808A,
Pacheer Commerc i al Centre,
555 Na nji ng R d. West
S hangha i, P.R. C . 200041
P ho ne: +86-2 1-621 5-5548
Fa x: +86-2 1-621 5-2 468
e-mail: chinasales@powerint.com
INDIA
261/ A, Ground Flo or
7th Main, 17th Cross,
Sadashivanagar
Bangalore, India 560080
Phone: +91-80-5113-8020
Fa x: +91 -8 0-511 3-8023
e-mai l: indias ale s @ powe r int.c om
KOREA
RM 6 02, 6F L
Korea City Air T erminal B/D,
159-6
Sa ms u ng-Do ng, Ka ngna m-G u,
Seou l, 135-728, Korea
Phone: +82-2-2016-6610
Fa x: +82-2 -2016 -66 30
e-mail:
koreasales@powerint.com
EUROPE HQ
1st Floor, St. James’s Hous e
East Street, Farnh am
Surrey , G U9 7TJ
Unite d Ki ngdom
P hone : +44 (0) 1252-7 30 -14 0
Fa x: +44 (0) 1252-7 27 -68 9
e-mail: e urosales@powerint.com
CHI N A (S HE N ZHE N)
Room 2206-2207, Block A,
Elec. Sci. Tech. Bldg.
2070 Shenna n Zho ng Rd.
Shenzhen, Guangdong,
China, 518031
P ho ne: +86-7 55-83 79-324 3
Fa x: +86-7 55-83 79- 5828
e-ma il: chinasales@po werint. co m
ITALY
V i a Vi tt or io Ven e t o 12
2009 1 B ress o MI
Italy
Phone: + 39-028-928-6000
Fa x: +39-02 8-928-6009
e-mail: eurosales@powerint.com
SINGAPORE
51 Newton Roa d,
#15 -08/10 Goldhill Plaza,
Si ngapore, 308900
Phone: +65-6358-2160
Fa x: +65 -6 358 -2 015
e-mail:
singaporesales@powerint.com
APPLICATIONS HOT LINE
World Wi de +1 -40 8-414 -9660
APPLICATI ONS FAX
World Wi de +1 -40 8-414 -9760
Page 28 of 28
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