Design Example Report
Title 24.5W Power Supply using DPA424G
Specification Input: -40 VDC
Output: -28V / 480mA, -65 V / 170mA
Application Telecom Line Card
Author Power Integrations Applications Department
Document
Number DER-43
Date November 18, 2004
Revision 1.0
Summary and Features
• Very high efficiency (>92 % at full load)
• Built-in input under-voltage lockout
• Single converter for both generating dual output voltages
• Non-isolated design
• Compact design
• Transistor feedback signal (instead of opto-coupler)
• Low component count
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.
Power Integrations
5245 Hellyer Avenue, San Jose, CA 95138 USA.
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DER-43 24.5 W Telecom Line Card PSU November 18, 2004
Table Of Contents
1 Introduction .................................................................................................................3
2 Power Supply Specification ........................................................................................4
3 Schematic ...................................................................................................................5
4 Circuit Operation.........................................................................................................6
4.1 General................................................................................................................6
4.2 Description...........................................................................................................6
5 BOM............................................................................................................................7
6 Layout .........................................................................................................................8
7 Transformer Design Spreadsheet...............................................................................9
8 Transformer Specification .........................................................................................11
8.1 Transformer Winding .........................................................................................11
8.2 Electrical Specifications .....................................................................................11
8.3 Materials ............................................................................................................11
8.4 Transformer Build Diagram................................................................................12
8.5 Transformer Construction ..................................................................................12
9 Efficiency ..................................................................................................................13
10 Regulation vs. Load...............................................................................................14
11 Low Load Power Consumption .............................................................................15
12 Drain Voltage and Current Waveforms..................................................................16
13 Transient Load ......................................................................................................17
13.1 Transient Load Test Setup ................................................................................17
13.2 Transient Load Performance .............................................................................18
14 Output Ripple ........................................................................................................19
14.1 Output Ripple Measurement Technique ............................................................19
14.2 Full Load Ripple Performance ...........................................................................20
14.3 No Load Ripple Performance ............................................................................20
15 Other results..........................................................................................................21
16 Revision History ....................................................................................................22
Important Note:
This board is designed to be non-isolated. Please take necessary safety precautions.
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-43 24.5 W Telecom Line Card PSU November 18, 2004
1 Introduction
This document is an engineering report describing a prototype power supply used on the
line cards of a PABX phone system, utilizing DPA424G. The power supply delivers 24.5
W continuous from a -40 VDC input. The power supply uses transistor based non-
isolated feedback instead of an opto-coupler (opto-couplers are not permitted for some
telecom supplies).
This document provides complete design information including specification, schematic,
bill of material and transformer design and construction information. The document also
provides performance information.
Figure 1 – Top view of board
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2 Power Supply Specification
Description Symbol Min Typ Max Units Comment
Input
Voltage VIN 32. 40 48 VDC
Under-Voltage VIN_UV 32.7 VDC
Power supply should not operate below
this input voltage.
Over-Voltage VIN_OV N/A VDC
Power supply should not operate above
this input voltage.
Output
Output Voltage 1 VOUT1 -26.6 -28 -29.4 V ± 5%
Output Ripple Voltage 1 VRIPPLE1 280 mVp-p 20 MHz bandwidth
Output Current 1 IOUT1 10 480 mA
Output Voltage 2 VOUT2 -61.75 -65 -68.25 V ± 5%
Output Ripple Voltage 2 VRIPPLE2 650 mVp-p 20 MHz bandwidth
Output Current 2 IOUT2 1 170 mA
Total Output Power
Average Output Power POUT1 13.44 W
Average Output Power POUT2 11.05 W
Average Output Power POUT_TOTAL 24.5 W
Average Output Power POUT_FAULT 100 W
Full Load Efficiency η 77 92 %
Environmental
Conducted EMI Meets CISPR22B / EN55022B
Safety
Designed to meet IEC950, UL1950
Class II
Ambient Temperature TAMB 0 40
oC Forced airflow
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3 Schematic
Figure 2 –Schematic
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4 Circuit Operation
4.1 General
The power supply uses a DPA424 device (U4), with integrated MOSFET and controller,
in a non-isolated flyback configuration. The circuit also uses the under-voltage shutdown
feature of the device.
4.2 Description
The input is decoupled by capacitor (C16). The DPA-Switch (U4) provides the PWM,
controller and main switching MOSFET for this flyback supply. Resistor R5 programs the
under-voltage shutdown of the DPA-Switch (U4). Startup will occur at voltages between
32.9 V (min) and 38.7 V (max). Resistor R14 programs the current limit of the DPA-
Switch. Capacitors C13 and C14 provide device decoupling with C14 also program the
startup and autorestart period of the device. Resistor R13 provides feedback
compensation in conjunction with C14. Components D2, C1, R1, R2 and R3 form an
RCD clamp circuit to limit the leakage inductance voltage spikes at primary turn-off. The
inductance of transformer T2 provides the energy storage and conversion component of
the circuit. The winding for the –28 V output is connected to the 0V input rail and thus is
non-isolated but the transformer does provide functional isolation (not safety isolation) for
the winding generating the –65 V output, generated from the –40 V DC input rail.
The –28 V output is rectified and filtered by diode D1 and capacitors C11, C17 and C18.
The –65 V output is rectified and filtered by diode D4 and capacitors C9 and C20 (note: -
the output capacitors used on the prototype are through-hole aluminum-electrolytic
capacitors but are intended to be replaced with SMD aluminum-electrolytic capacitors,
that were not available in time for the construction of this prototype). In this power supply
the input rails are used as references to generate the output voltages, as such we need
to make sure that there is not primary side switching ripple on the 0 V and –40 V rails.
This is achieved using additional decoupling capacitors C19 and C15. Without these two
capacitors, all the ripple generated by primary switching, would also be superimposed on
the output voltages. Resistor R8 senses the –65 V output voltage and components R11,
Q3 and R19 form an inverting follower to provide sense of the –28 V output voltage. Both
of these sense signals are summed and generate a voltage on resistor R15, which
controls the LM431 (U3). Components R12 and C12 provide compensation for U3, to
make sure that it’s frequency response is limited only to low-frequency signals. Resistor
R20 provides bias current to U3 (from the –40 V rail). Components R18, Q2, R16 provide
level shifting to transmit the feedback signal. Capacitor C21 increase the high frequency
response of the loop. Components R17, Q1 provide the final connection of the to the
CONTROL pin of U4, with diode D5 preventing reverse biasing of the Q1 collector-base
junction when the base is below CONTROL pin potential (which happens at startup).
Resistor R17 in conjunction with R16 and R18 program the DC gain of the loop.
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5 BOM
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Item Qty. Ref. Description Mfg Part Number Mfg
1 1 C1 1 nF, 50 V, Ceramic, X7R, 0805 ECJ-2VB1H102K Panasonic
2 6
C9 C11
C17 C18
C19 C20
47 uF, 50 V, Electrolytic, Low ESR, 450
mOhm, (6.3 x 11.5) LXZ50VB47RMF11LL United Chemi-Con
3 1 C12 1 uF, 25 V, Ceramic, X7R, 1206 ECJ-3YB1E105K Panasonic
4 1 C13 220 nF, 25 V, Ceramic, X7R, 0805 ECJ-2YB1E224K Panasonic
5 1 C14 47 uF, 6.3 V, Electrolytic, (4 x 5.4), SMD EEVHA0L470WR Panasonic
6 2 C15 C16 220 nF, 50 V, Ceramic, X7R, 1206 ECJ-3YB1H224K Panasonic
7 1 C21 2.2 uF, 25 V, Ceramic, X7R, 1206 ECJ-3YB1E225K Panasonic
8 2 D1 D4 60 V, 2 A, Schottky, DO-214AA SS26 Vishay
9 1 D2
100 V, 1 A, Ultrafast Recovery, 25 ns, DO-
214AC ES1B Vishay
10 1 D5 75 V, 0.15 A, Fast Switching, 4 ns, MELF LL4148 Diode Inc.
11 5
J1 J2 J3
J4 J5 PCB Terminal Hole, 22 AWG N/A N/A
12 2 Q1 Q3
PNP, Small Signal BJT, 40 V, 0.2 A, SOT-
323 MMST3906-7 Diodes Inc
13 1 Q2
NPN, Small Signal BJT, 40 V, 0.2 A, SOT-
323 MMST3904 Diodes Inc
14 3 R1 R2 R3 27 k, 5%, 1/8 W, Metal Film, 0805 ERJ-6GEYJ273V Panasonic
15 1 R5 619 k, 1%, 1/8 W, Metal Film, 0805 ERJ-6ENF6193V Panasonic
16 1 R8 499 k, 1%, 1/8 W, Metal Film, 0805 ERJ-6ENF4993V Panasonic
17 1 R11 215 k, 1%, 1/8 W, Metal Film, 0805 ERJ-6ENF2153V Panasonic
18 1 R12 220 R, 5%, 1/10 W, Metal Film, 0603 ERJ-3GEYJ221V Panasonic
19 1 R13 10 R, 5%, 1/10 W, Metal Film, 0603 ERJ-3GEYJ100V Panasonic
20 1 R14 9.53 k, 1%, 1/16 W, Metal Film, 0603 ERJ-3EKF9531V Panasonic
21 1 R15 9.09 k, 1%, 1/16 W, Metal Film, 0603 ERJ-3EKF9091V Panasonic
22 1 R16 2.7 k, 5%, 1/8 W, Metal Film, 0805 ERJ-6GEYJ272V Panasonic
23 1 R17 390 R, 5%, 1/8 W, Metal Film, 0805 ERJ-6GEYJ391V Panasonic
24 1 R18 5.6 k, 5%, 1/8 W, Metal Film, 0805 ERJ-6GEYJ562V Panasonic
25 1 R19 1 k, 5%, 1/10 W, Metal Film, 0603 ERJ-3GEYJ102V Panasonic
26 1 R20 47 k, 5%, 1/8 W, Metal Film, 0805 ERJ-6GEYJ473V Panasonic
27 1 T2 Bobbin, PR14x8, Horizontal, 10 pins, SMD S-1403 Pin Shine
28 1 U3
2.495 V Shunt Regulator IC, 2%, -40 to
85C, SOT23 LM431AIM
National
Semiconductor
29 1 U4 DPA-Switch, DPA424G, DIP-8B DPA424G Power Integrations
43
TOTAL COMPONENTS
DER-43 24.5 W Telecom Line Card PSU November 18, 2004
6 Layout
Figure 3 – PC-Board Layout
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7 Transformer Design Spreadsheet
DCDC
_
DPASwitch
_
Flyback_013004_Re
vision1J. Copyright
Power Integrations
2004 INPUT INFO OUTPUT UNITS DPASwitch_Flyback_013004 - Continuous/Discontinuous mode Spreadsheet.
C
ENTER APPLICATION VARIABLES
VDCMIN 36 Volts Minimum DC Input Voltage
VDCMAX 48 Volts Maximum DC Input Voltage
VO 28 Volts Output Voltage
PO 17.7 Watts Output Power
n 0.8 Efficiency Estimate
Z 0.7 Loss Allocation Factor, (0.7 Recommended)
VB 14 Volts Bias Voltage (Recommended between 12V and 18V)
UV AND OV PARAMETERS
min max
VUVOFF 30.05 30.05 33.14551Volts Minimum undervoltage On-Off threshold
VUVON 32.21685 34.69326Volts Maximum undervoltage Off-On threshold (turn-on)
VOVON 74.93483 - Volts Minimum overvoltage Off-On threshold
VOVOFF 94.74607Volts Maximum overvoltage On-Off threshold (turn-off)
RL 619.1011k-Ohms
ENTER DPASWITCH VARIABLES
DPASWITCH 16VDC 36VDC
Chosen Device #N/A Power Out11W 26W
ILIMITMAX #N/A 2.68
A
mps From DPASWITCH Data Sheet
Frequency Enter 'F' for fS = 400KHz and 'L' for fS = 300KHz
fS #N/A Hertz DPASWITCH Switching Frequency
VOR 50 50 Volts Reflected Output Voltage
KI 0.80 0.8 Current Limit Reduction Factor
ILIMITEXT 1.856
A
mps Minimum External Current limit
RX 9.501216k-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
Core Manuf
Bobbin Manuf
Core PR14x8 P/N: B65755-J-R87
Bobbin PR14x8_Bobbin P/N: B65542-B-T1
A
E 0.253 cm^2 Core Effective Cross Sectional Area
LE 2.53 cm Core Effective Path Length
A
L 2000 nH/T^2 Ungapped Core Effective Inductance
BW 4.4 mm Bobbin Physical Winding Width
M 0 mm Safety Margin Width (Half the Primary to Secondary Creepage Distance)
L 2 Number of Primary Layers
NS 9 Number of Secondary Turns
dpa424
F
pr14x8
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CURRENT WAVEFORM SHAPE PARAMETERS
DMAX 0.588235 Maximum Duty Cycle
IAVG 0.614583 Amps Average Primary Current
IP 1.514191 Amps Peak Primary Current
IR 0.938798 Amps Primary Ripple Current
IRMS 0.827837 Amps Primary RMS Current
TRANSFORMER PRIMARY DESIGN PARAMETERS
LP 56.54287 uHenries Primary Inductance
NP 15.78947 Primary Winding Number of Turns
NB 4.642105 Bias Winding Number of Turns
ALG 226.7997 nH/T^2 Gapped Core Effective Inductance
BP 2627.046 Gauss Peak Flux density during transients (Limit to 3000 Gauss)
BM 2143.238 Gauss Maximum Flux Density
BAC 664.4036 Gauss AC Flux Density for Core Loss Curves (0.5 X Peak to Peak)
ur 1591.546 Relative Permeability of Ungapped Core
LG 0.124284 mm Gap Length (Lg >> 0.051 mm)
BWE 8.8 mm Effective Bobbin Width
TRANSFORMER SECONDARY DESIGN PARAMETE
R
ISP 2.656475 Amps Peak Secondary Current
ISRMS 1.21512 Amps Secondary RMS Current
IO 0.632143 Amps Power Supply Output Current
IRIPPLE 1.037744 Amps Output Capacitor RMS Ripple Current
VOLTAGE STRESS PARAMETERS
VDRAIN 173 Volts Maximum Drain Voltage (Includes Effect of Leakage Inductance)
PIVS 55.36 Volts Output Rectifier Maximum Peak Inverse Voltage
PIVB 28.112 Volts Bias Rectifier Maximum Peak Inverse Voltage
ADDITIONAL OUTPUTS
V_OUT2 28.0000 Volts Auxiliary Output Voltage
VD_OUT2 0.5000 Volts Auxiliary Diode Forward Voltage Drop
N_OUT2 9 Auxiliary Number of Turns
PIV_OUT2 55.36 Volts Auxiliary Rectifier Maximum Peak Inverse Voltage
V_OUT3 25 Volts Auxiliary Output Voltage
VD_OUT3 0.5 Volts Auxiliary Diode Forward Voltage Drop
N_OUT3 8.052632 Auxiliary Number of Turns
PIV_OUT3 49.48 Volts Auxiliary Rectifier Maximum Peak Inverse Voltage
Note1: the PO value in this spreadsheet is 17.7 W. The power supply provides –28 V at
480 mA and –65 V at 170 mA which would give a total of 24.5 W. However the –65 V
output is derived from the –40 VDC input, thus the switched-mode converter only
provides the remaining –25V at 170 mA, saving (-40 V x 170 mA = 6.8 W) to give a total
converted power of 17.7 W.
Note2: the second output (shown as VOUT3) has a voltage of - 25 V. This is the output
that combined with –40 VDC gives –65 V output.
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8 Transformer Specification
8.1 Transformer Winding
W3: 8T
3 x 32 AWG
6
5
W1: 8T
2 x 31 AWG
2
W2: 9T
3 x 32 AWG
8
7
1
W4: 8T
2 x 31 AWG
3
Figure 4 –Transformer Electrical Diagram
8.2 Electrical Specifications
Electrical Strength Non-isolated N/A
Primary Inductance Pins 1-2, all other windings open, measured at
400 kHz, 0.4 VRMS 57 µH, -0/+20%
Resonant Frequency Pins 1-2, all other windings open 5 MHz (Min.)
Primary Leakage Inductance Pins 1-2, with Pins 5,6,7,8 shorted, measured at
400 kHz, 0.4 VRMS 500 nH (Max.)
8.3 Materials
Item Description
[1] Core: PR14x8 ALG=227 nH/t^2
[2] Bobbin: PR14x8 8-pin vertical
[3a] 31AWG Doubled insulated
[3b] 32 AWG Doubled insulated
[6] Tape:
[8] Varnish
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8.4 Transformer Build Diagram
W2
Tape
6
2
3 W1
1 W4
Tape
Tape
7
3
5
8 W3
Tape
Tape
Figure 5 – Transformer Build Diagram.
8.5 Transformer Construction
W1 Start at Pin 2. Wind 8 turns bifilar item [3a]. Finish on pin 3
Tape Use layer of item [6].
W2 Start at Pin 6. Wind 9 turns trifilar item [3b]. Finish on pin 5
Tape Use layer of item [6].
W3 Start at Pins 7. Wind 8 turns trifilar item [3b]. Finish on pin 8
Tape Use layer of item [6].
W4 Start at Pin 3. Wind 8 turns bifilar item [3a]. Finish on pin 1.
Other
When using PC-board (App140512_Brd_082704A-3), remove pin 3 PC-
board solder tab, to prevent shorting on the PC-board. This corrects an
error on the PC-board.
Outer Wrap Wrap windings with 3 layers of tape [item [7].
Final Assembly Assemble and secure core halves. Varnish impregnate (item [8]).
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9 Efficiency
Efficiency vs Line/Load
0%
20%
40%
60%
80%
100%
0 102030
Pout (W)
Efficiency (%)
Efficiency
Figure 6 - 16.5V Output: Efficiency vs. Input Voltage, Room Temperature, 60 Hz.
Note1: the above data was taken with various load combinations of –65V and –28V
loads.
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10 Regulation vs. Load
Regulation vs Load
85.0%
90.0%
95.0%
100.0%
105.0%
110.0%
115.0%
0.0 5.0 10.0 15.0
Pout (W)
Regulation (%)
-65 VDC Output
-28 VDC Output
Figure 7 - 16.5V Output: Regulation vs. Output Load, Room Temperature, 60 Hz.
Note1: the above data was taken with various load combinations of –65V and –28V
loads.
Note2: The power supply regulation can be further optimized, by adjusting the relative
weighting on output voltage sense resistors R8 and R11. Also the resistor R15 could be
increased to lower both output voltages and center them more accurately in the middle of
the allowed specification. A min. load could also be added to help the light-load regulation
by preventing peak charging on the –28 VDC output.
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11 Low Load Power Consumption
Low Load Power Consumption
0.00
0.50
1.00
1.50
2.00
2.50
3.00
0.00 0.20 0.40 0.60 0.80 1.00
Pout (W)
Pin (W)
No Load
Figure 8 - No Load/Min. Load Input Consumption at –40 V input (note: min load –28 V @ 10mA and –65 V
@ 5 mA)
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12 Drain Voltage and Current Waveforms
Figure 9 – Drain Voltage and Current, -32.7 VDC,
-28 V: 0.48 A; -65 V: 0.18 A
Top: 50 V/div.
Bottom: 0.5 A/div, 500 ns / div.
Figure 10 – Drain Voltage and Current, -40 VDC,
28 V: 0.48 A; -65 V: 0.18 A
Top: 50 V/div.
Bottom: 0.5 A/div, 500 ns / div.
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13 Transient Load
13.1 Transient Load Test Setup
For transient load tests, additional capacitors were added to eliminate noise pickup
during transient load tests (1uF/50V electrolytic in parallel with a 0.1uF/50V ceramic).
These were placed at the output of the power supply. From there the lead length to the
electronic load was approximately 12 inches to the electronic load. Voltage probes (x1
probes) were placed right at the output of the power supply.
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13.2 Transient Load Performance
Figure 11 – Transient Response, -40 VDC, -28 V: 0.01 –
0.48 A (100ms-100ms), -65 V: 0.18 A
Top: -65 V Voltage, 1V/div.
Middle: -28 V Voltage, 1V/div., 50 ms / div.
Figure 12 – Transient Response, -40 VDC, 28 V: 0.48 A,
-65 V: 0.005 - 0.18 A (100ms-100ms)
Top: -65 V Voltage, 1V/div.
Middle: -28 V Voltage, 1V/div., 50 ms / div.
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14 Output Ripple
14.1 Output Ripple Measurement Technique
Measurements made at the end of 6ft output cord and a resistor load was used. 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 13 and figure 14.
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 13 - Oscilloscope Probe Prepared for Ripple Measurement. (End Cap and Ground Lead Removed)
Figure 14 - 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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14.2 Full Load Ripple Performance
Figure 15 – Ripple, -32.7 VDC, -28 V: 0.48 A, -65 V:
0.18 A
Top: -65 V Voltage, 1V/div.
Middle: -28 V Voltage, 1V/div., 2 µs / div.
Figure 16 – Ripple, -40 VDC, -28 V: 0.48 A, 65 V: 0.18 A
Top: -65 V Voltage, 1V/div.
Middle: -28 V Voltage, 1V/div., 2 µs / div.
14.3 No Load Ripple Performance
Figure 17 – Ripple, -32.7 VDC, -28 V: 0 A, 65 V: 0 A
Top: -65 V Voltage, 1V/div.
Middle: -28 V Voltage, 1V/div., 2 µs / div.
Figure 18 – Ripple, -40 VDC, -28 V: 0 A, 65 V: 0 A
Top: -65 V Voltage, 1V/div.
Middle: -28 V Voltage, 1V/div., 2 µs / div.
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15 Other Test Results
During short circuit, the following happened:
- for –28 V short circuit, the power supply went into autorestart
- for –65 V short circuit, the power supply shut-down. The power supply would
normally go into autorestart under this condition. However, since the –40 VDC
input rail is used to derive the output of –65 VDC, when the –65 VDC output is
shorted, this also shorts the input voltage and causes the power supply to go into
under-voltage shutdown (which occurs when the input voltage drops below ~ 32
VDC).
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16 Revision History
Date Author Revision Description & changes Reviewed
November 18, 2004 RM 1.0 First release VC / AM
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FITNESS FOR A PARTICULAR PURPOSE, AND NON-INFRINGEMENT OF THIRD PARTY RIGHTS.
PATENT INFORMATION
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.
The PI Logo, TOPSwitch, TinySwitch, LinkSwitch, and EcoSmart are registered trademarks of Power
Integrations. PI Expert and DPA-Switch are trademarks of Power Integrations.
© Copyright 2004, Power Integrations.
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: +49-895-527-3910
Fax: +49-895-527-3920
e-mail: eurosales@powerint.com
JAPAN
Keihin-Tatemono 1st Bldg.
12-20 Shin-Yokohama,
2-Chome,
Kohoku-ku, Yokohama-shi,
Kanagawa 222-0033, Japan
Phone: +81-45-471-1021
Fax: +81-45-471-3717
e-mail:
japansales@powerint.com
TAIWAN
17F-3, No. 510,
Chung Hsiao E. Rd., Sec. 5,
Taipei, Taiwan 110, R.O.C.
Phone: +886-2-2727-1221
Fax: +886-2-2727-1223
e-mail:
taiwansales@powerint.com
CHINA (SHANGHAI)
Rm 807, Pacheer,
Commercial Centre,
555 Nanjing West Road,
Shanghai, 200041, China
Phone: +86-21-6215-5548
Fax: +86-21-6215-2468
e-mail:
chinasales@powerint.com
INDIA (TECHNICAL SUPPORT)
Innovatech
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
8th Floor, DongSung Bldg.
17-8 Yoido-dong,
Youngdeungpo-gu,
Seoul, 150-874, Korea
Phone: +82-2-782-2840
Fax: +82-2-782-4427
e-mail:
koreasales@powerint.com
UK (EUROPE & AFRICA
HEADQUARTERS)
1st Floor, St. James’s House
East Street
Farnham, Surrey GU9 7TJ
United Kingdom
Phone: +44-1252-730-140
Fax: +44-1252-727-689
e-mail: eurosales@powerint.com
CHINA (SHENZHEN)
Rm# 1705, Bao Hua Bldg.
1016 Hua Qiang Bei Lu,
Shenzhen, Guangdong,
518031, China
Phone: +86-755-8367-5143
Fax: +86-755-8377-9610
e-mail:
chinasales@powerint.com
ITALY
Via Vittorio Veneto 12, Bresso,
Milano,
20091, Italy
Phone: +39-028-928-6001
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.co
m
APPLICATIONS HOTLINE
World Wide +1-408-414-9660
APPLICATIONS FAX
World Wide +1-408-414-9760
ER or EPR template – Rev 3.6 – Single sided
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Power Integrations
Tel: +1 408 414 9200 Fax: +1 408 414 9201
www.powerint.com
