Title
Reference Design Report for a 35 W Power
Supply Using TOPSwitchTM-HX TOP258PN
Specification
90 VAC to 265 VAC Input;
5 V, 2.2 A and 12 V, 2 A Outputs
Application
LCD Monitor
Author
Applications Engineering Department
Document
Number
RDR-142
Date
August 07, 2014
Revision
1.3
Summary and Features
• Low cost, low component count, high efficiency
• Delivers 35 W at 50 °C ambient without requiring an external heat sink
• Meets output cross regulation requirements without linear regulators
• EcoSmartTM – meets requirements for low no-load and standby power consumption
• 0.42 W output power for 82% full load efficiency
• Integrated safety/reliability features
• Accurate, auto-recovering, hysteretic thermal shutdown function maintains safe
PCB temperatures under all conditions
• Auto-restart protects against output short-circuits and open feedback loops
• Output OVP protection configurable for latching or self-recovering
• Input UV prevents power up / power down output glitches
• Meets EN55022 and CISPR-22 Class B conducted EMI with >10 dBµV margin
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.
Tel: +1 408 414 9200 Fax: +1 408 414 9201
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RDR-142 35 W, TOP258PN Dual Output Supply
07-Aug-14
Table of Contents
1
2
3
4
Introduction ................................................................................................................. 4
Power Supply Specification ........................................................................................ 5
Schematic ................................................................................................................... 6
Circuit Description ...................................................................................................... 7
4.1
Input EMI Filtering ............................................................................................... 7
4.2
TOPSwitch-HX Primary ....................................................................................... 7
4.3
Output Rectification ............................................................................................. 8
4.4
Output Feedback ................................................................................................. 9
4.5
PCB Layout ....................................................................................................... 10
5 Bill of Materials ......................................................................................................... 11
6 Transformer Specification ......................................................................................... 13
6.1
Electrical Diagram ............................................................................................. 13
6.2
Electrical Specifications ..................................................................................... 13
6.3
Materials ............................................................................................................ 13
6.4
Transformer Build Diagram ............................................................................... 14
6.5
Transformer Construction .................................................................................. 15
7 Transformer Design Spreadsheet............................................................................. 16
8 Performance Data .................................................................................................... 20
8.1
Efficiency ........................................................................................................... 20
8.1.1
Active Mode CEC Measurement Data........................................................ 21
8.2
No-Load Input Power ........................................................................................ 22
8.3
Available Standby Output Power ....................................................................... 23
9 Regulation ................................................................................................................ 24
9.1.1
Load ........................................................................................................... 24
9.1.2
Line ............................................................................................................ 25
9.1.3
Cross Regulation Matrix ............................................................................. 26
10
Thermal Performance ........................................................................................... 27
11
Waveforms ............................................................................................................ 29
11.1 Drain Voltage and Current, Normal Operation................................................... 29
11.2 Output Voltage Start-up Profile.......................................................................... 29
11.3 Drain Voltage and Current Start-up Profile ........................................................ 31
11.4 Load Transient Response (75% to 100% Load Step) ....................................... 32
11.5 Output Overvoltage Protection .......................................................................... 34
11.6 Output Ripple Measurements ............................................................................ 35
11.6.1 Ripple Measurement Technique ................................................................ 35
11.6.2 Measurement Results ................................................................................ 36
12
Line Surge............................................................................................................. 38
13
Control Loop Measurements ................................................................................. 39
13.1 90 VAC Maximum Load..................................................................................... 39
13.2 265 VAC Maximum Load................................................................................... 40
14
Conducted EMI ..................................................................................................... 41
15
Revision History .................................................................................................... 42
Important Note:
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Page 2 of 43
07-Aug-14
RDR-142 35 W, TOP258PN Dual Output Supply
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 isolation transformer to provide the AC input to the prototype board.
Page 3 of 43
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RDR-142 35 W, TOP258PN Dual Output Supply
07-Aug-14
1 Introduction
This document is an engineering report describing a LCD Monitor power supply utilizing a
TOP258PN. This power supply is intended as a general purpose evaluation platform for
TOPSwitch-HX.
The document contains the power supply specification, schematic, bill of materials,
transformer documentation, printed circuit layout, and performance data.
Figure 1 – Populated Circuit Board Photograph (5”L x 2.84”W x 1.16”H).
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Page 4 of 43
07-Aug-14
RDR-142 35 W, TOP258PN Dual Output Supply
2 Power Supply Specification
Description
Symbol
Min
Typ
Max
Units
Comment
265
64
0.3
VAC
Hz
W
3 Wire Input
5.25
100
2.2
14.4
V
mV
A
V
± 5%
20 MHz Bandwidth
500
mV
20 MHz Bandwidth
2
A
Input
Voltage
Frequency
No-load Input Power (230 VAC)
Output
Output Voltage 1
Output Ripple Voltage 1
Output Current 1
Output Voltage 2
VIN
fLINE
90
47
50/60
VOUT1
VRIPPLE1
IOUT1
VOUT2
4.75
5
0
9.6
12
Output Ripple Voltage 2
VRIPPLE2
Output Current 2
Total Output Power
Continuous Output Power
Efficiency
Full Load
IOUT2
0
POUT
η
35
Required Average Efficiency at
25, 50, 75 and 100 % of POUT
W
82
Standby Input Power
*
W
Measured at POUT 25 oC
5 V @ 82 mA, 12 V @ 0 mA;
VIN at 264 VAC
%
Per California Energy Commission
(CEC) / Energy Star requirements
%
1
ηCEC
± 20%
81
Environmental
Conducted EMI
Meets CISPR22B / EN55022B
Designed to meet IEC950, UL1950
Class II
Safety
Surge
Differential
Common Mode
Surge
Ring Wave
Ambient Temperature
TAMB
1
2
kV
kV
1
kV
0
50
o
C
1.2/50 µs surge, IEC 1000-4-5,
Series Impedance:
Differential Mode: 2 Ω
Common Mode: 12 Ω
100 kHz ring wave, 500 A Short
Circuit Current, Differential and
Common Mode
Free Convection, Sea Level
*Shown for information only as CEC requirement does not apply to internal power supplies
Page 5 of 43
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RDR-142 35 W, TOP258PN Dual Output Supply
07-Aug-14
3 Schematic
*
*Optional for 2-wire input, floating output
Figure 2 – Schematic.
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Page 6 of 43
07-Aug-14
RDR-142 35 W, TOP258PN Dual Output Supply
4 Circuit Description
A flyback converter configuration built around TOP258PN is used in this power supply to
obtain two output voltages. The 5 V output can supply a load current of 2.2 A, and the
12 V output can supply a load current of 2.0 A. This power supply can operate between
90 – 264 VAC. The 5 V output is the main regulated output. This output is regulated
using a TL431 voltage reference. Some feedback is also derived from the 12 V output for
improved cross regulation.
4.1 Input EMI Filtering
The three wire AC supply is connected to the circuit using connector J1. Fuse F1
provides protection against circuit faults and effectively isolates the circuit from the AC
supply source. Thermistor RT1 limits the inrush current drawn by the circuit at start up.
Optional capacitors C1 and C2 are Y capacitors connected from the Line/Neutral to Earth
to reduce common mode EMI.
Capacitor C3 is the X capacitor and helps to reduce the differential mode EMI. Resistors
R1 and R2 discharge C3 on AC removal, preventing potential user shock. Inductor L1 is
a common-mode inductor and helps in filtering common-mode EMI from coupling back to
the AC source.
Diodes D1, D2, D3 and D4 form a bridge rectifier. The bridge rectifier rectifies the
incoming AC supply to DC, which is filtered by capacitor C4.
Diodes D1 and D3 are fast recovery type diodes. These diodes recover very quickly
when the voltage across them reverses. This reduces excitation of stray line inductance
in the AC input by reducing the subsequent high frequency turnoff snap and hence EMI.
Only 2 of the 4 diodes in the bridge need to be fast recovery type, since 2 diodes conduct
in each half cycle.
4.2 TOPSwitch-HX Primary
Resistor R3 and R4 provide line voltage sensing and provide a current to U1, which is
proportional to the DC voltage across capacitor C4. At approximately 95 V DC, the
current through these resistors exceeds the line under-voltage threshold of 25 µA, which
results in enabling of U1.
The TOPSwitch-HX IC regulates the output using PWM-based voltage mode control. At
high loads the controller operates at full switching frequency (66 kHz for P package
devices). The duty cycle is controlled based on the CONTROL pin current to regulate the
output voltage.
The internal current limit provides cycle-by-cycle peak current limit protection. The
TOPSwitch-HX controller has a second current limit comparator allowing monitoring the
actual peak drain current (IP) relative to the programmed current limit ILIMITEXT. As soon as
the ratio IP/ILIMITEXT falls below 55%, the peak drain current is held constant. The output is
Page 7 of 43
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RDR-142 35 W, TOP258PN Dual Output Supply
07-Aug-14
then regulated by modulating the switching frequency (variable frequency PWM control).
As the load decreases further, the switching frequency decreases linearly from full
frequency down to 30 kHz.
Once the switching frequency has reached 30 kHz the controller keeps this switching
frequency constant and the peak current is reduced to regulate the output (fixed
frequency, direct duty cycle PWM control).
As the load is further reduced and the ratio IP/ILIMITEXT falls below 25%, the controller will
enter a multi-cycle-modulation mode for excellent efficiency at light load or standby
operation and low no-load input power consumption.
Diode D5, together with R6, R7, C6 and Zener VR1, forms a clamp network that limits the
drain voltage of U1 at the instant of turn-off. Zener VR1 provides a defined maximum
clamp voltage and typically only conducts during fault conditions such as overload. This
allows the RCD clamp (R6, C6 and D5) to be sized for normal operation, thereby
maximizing efficiency at light load. Resistor R7 is required due to the choice of a fast
recovery diode for D5. A fast versus ultrafast recovery diode allows some recovery of the
clamp energy but requires R7 to limit reverse diode current and dampen high frequency
ringing.
The output of the bias winding is rectified by diode D6 and filtered by resistor R10 and
capacitor C10. This rectified and filtered output is used by the optocoupler U2 to provide
the control current to the control terminal of U1.
Should the feedback circuit fail (open loop condition), the output of the power supply will
exceed the regulation limits. This increased voltage at output will also result in an
increased voltage at the output of the bias winding. Zener VR2 will break down and
current will flow into the “M” pin of IC U1, thus initiating a hysteretic OVP shutdown with
automatic restart attempts. Resistor R5 limits the current into the M pin; if latching OVP is
desired, the value of R5 can be reduced to 20 Ω.
The output voltage of the power supply is maintained in regulation by the feedback circuit
on the secondary side of the circuit. The feedback circuit controls the output voltage by
changing the optocoupler current. Change in the optocoupler diode current results in a
change of current into the control pin of IC U1. Variation of this current results in variation
of duty cycle and hence the output voltage of the power supply.
4.3 Output Rectification
Output rectification for the 5 V output is provided by diode D8. Low ESR capacitor C17
provides filtering. Inductor L3 and capacitor C18 form a second stage filter that
significantly attenuates the switching ripple across C17 and ensures a low ripple output.
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Page 8 of 43
07-Aug-14
RDR-142 35 W, TOP258PN Dual Output Supply
Output rectification for the 12 V output is provided by diode D7. Low ESR capacitors C13
and C14 provide filtering. Inductor L2 and capacitor C15 form a second stage filter that
significantly attenuates the switching ripple and ensures low ripple at the output.
Snubber networks comprising R11, C12 and R12, and C16 damp high frequency ringing
across diodes D7 and D8, which results from leakage inductance of the transformer
windings and the secondary trace inductances.
4.4 Output Feedback
Output voltage is controlled using the shunt regulator TL431 (U3). Diode D9, capacitor
C20 and resistor R16 form the soft finish circuit. At start-up, capacitor C20 is discharged.
As the output voltage starts rising, current flows into the optocoupler diode (U2A) via
resistor R13 and diode D9. This provides feedback to the circuit on the primary side. The
current in the optocoupler diode U2A gradually decreases as capacitor C20 charges and
U3 becomes operational. This ensures that the output voltage increases gradually and
settles to the final value without any overshoot. Resistor R16 provides a discharge path
for C20 into the load at power down. Diode D9 isolates C20 from the feedback circuit
after start-up.
Resistor R18, R20 and R21 form a voltage divider network that senses the output voltage
from both the outputs for better cross-regulation. Resistor R19 and Zener VR3 improve
cross regulation when only the 5 V output is loaded, which results in the 12 V output
operating at the higher end of the specification.
Resistors R13, R17 and capacitor C21 set the frequency response of the feedback
circuit. Capacitor C19 and resistor R14 form the phase boost network that provides
adequate phase margin to ensure stable operation over the entire operating voltage
range.
Resistor R15 provides the bias current required by the IC U3 and is placed in parallel with
U2A to ensure that the bias current to the IC does not become a part of the feedback
current. Resistor R13 sets the overall DC loop gain and limits the current through U2A
during transient conditions.
Page 9 of 43
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RDR-142 35 W, TOP258PN Dual Output Supply
4.5
07-Aug-14
PCB Layout
Figure 3 – Printed Circuit Layout.
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Page 10 of 43
07-Aug-14
RDR-142 35 W, TOP258PN Dual Output Supply
5 Bill of Materials
Item
2
Qty
1
Ref Des
C3
3
1
C4
4
5
6
7
8
9
1
2
1
1
2
2
C6
C7 C11
C8
C9
C10 C20
C12 C16
10
2
C13 C14
11
1
C15
12
1
C17
13
1
C18
14
15
1
1
C19
C21
16
2
D1 D3
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
2
2
1
1
1
1
1
2
1
1
1
1
2
2
2
1
1
1
1
1
1
2
1
1
1
2
1
1
1
1
1
D2 D4
D5 D6
D7
D8
D9
F1
J1
J2 J3
JP1
JP2
JP3
L1
L2 L3
R1 R2
R3 R4
R5
R6
R7
R8
R9
R10
R11 R12
R13
R14
R15
R16 R17
R18
R19
R20
R21
RT1
48
1
T1
Page 11 of 43
Description
220 nF, 275 VAC, Film, X2
100 µF, 400 V, Electrolytic, Low ESR,
630 mΩ (16 x 40)
3.9 nF, 1 kV, Disc Ceramic, Y5P
2.2 nF, Ceramic, Y1
100 nF, 50 V, Ceramic, Z5U
47 µF, 16 V, Electrolytic, Gen Purpose, (5 x 11.5)
10 µF, 50 V, Electrolytic, Gen Purpose, (5 x 11)
470 pF, 100 V, Ceramic, COG
680 µF, 25 V, Electrolytic, Very Low ESR,
23 mΩ, (10 x 20)
220 µF, 25 V, Electrolytic, Low ESR,
120 mΩ, (8 x 12)
2200 µF, 10 V, Electrolytic, Very Low ESR,
21 mΩ, (12.5 x 20)
220 µF, 10 V, Electrolytic, Low ESR,
250 mΩ, (6.3 x 11.5)
1.0 µF, 50 V, Ceramic, X7R
220 nF, 50 V, Ceramic, X7R
600 V, 1 A, Fast Recovery Diode,
200 ns, DO-41
1000 V, 1 A, Rectifier, DO-41
800 V, 1 A, Fast Recovery Diode, 500 ns, DO-41
60 V, 5 A, Schottky, DO-201AD
30 V, 5 A, Schottky, DO-201AD
75 V, 300 mA, Fast Switching, DO-35
3.15 A, 250V,Fast, TR5
5 Position (1 x 5) header, 0.156 pitch
2 Position (1 x 2) header, 0.156 pitch
Wire Jumper, Non insulated, #22 AWG, 0.4 in
Wire Jumper, Non insulated, #22 AWG, 0.8 in
Wire Jumper, Non insulated, #22 AWG, 0.3 in
6.8 mH, 0.8 A, Common Mode Choke
3.3 µH, 5.0 A
1 MΩ, 5%, 1/4 W, Carbon Film
2.0 MΩ, 5%, 1/4 W, Carbon Film
5.1 kΩ, 5%, 1/4 W, Carbon Film
22 kΩ, 5%, 2 W, Metal Oxide
20 Ω, 5%, 1/2 W, Carbon Film
6.8 Ω, 5%, 1/8 W, Carbon Film
100 Ω, 5%, 1/4 W, Carbon Film
0 Ω, 5%, 1/4 W, Carbon Film
33 Ω, 5%, 1/4 W, Carbon Film
330 Ω, 5%, 1/4 W, Carbon Film
22 Ω, 5%, 1/4 W, Carbon Film
1 kΩ, 5%, 1/4 W, Carbon Film
10 kΩ, 5%, 1/4 W, Carbon Film
196 kΩ, 1%, 1/4 W, Metal Film
10 Ω, 5%, 1/4 W, Carbon Film
12.4 kΩ, 1%, 1/4 W, Metal Film
10 kΩ, 1%, 1/4 W, Metal Film
NTC Thermistor, 10 Ω, 1.7 A
Core
Bobbin: EER28, Horizontal, 12 pins (6/6),
Mfg Part Number
ECQ-U2A224ML
B37984M5105K000
B37987F5224K000
Mfg
Panasonic
Nippon
Chemi-Con
Panasonic
Vishay
Kemet
Panasonic
Panasonic
AVX
Nippon
Chemi-Con
Nippon
Chemi-Con
Nippon
Chemi-Con
Nippon
Chemi-Con
Epcos
Epcos
1N4937RLG
On Semi
1N4007
FR106
SB560
SB530
1N4148
37013150410
26-48-1055
26-48-1025
298
298
298
ELF15N008
RFB0807-3R3L
CFR-25JB-1M0
CFR-25JB-2M0
CFR-25JB-5K1
RSF200JB-22K
CFR-50JB-20R
CFR-12JB-6R8
CFR-25JB-100R
ZOR-25-B-52-0R
CFR-25JB-33R
CFR-25JB-330R
CFR-25JB-22R
CFR-25JB-1K0
CFR-25JB-10K
MFR-25FBF-196K
CFR-25JB-10R
MFR-25FBF-12K4
ERO-S2PHF1002
CL-120
PC40EER28-Z
YC-2806-5
Vishay
Diodes, Inc.
Vishay
Fairchild
Vishay
Wickman
Molex
Molex
Alpha
Alpha
Alpha
Panasonic
Coilcraft
Yageo
Yageo
Yageo
Yageo
Yageo
Yageo
Yageo
Yageo
Yageo
Yageo
Yageo
Yageo
Yageo
Yageo
Yageo
Yageo
Panasonic
Thermometrics
TDK
Ying-Chin
EKMX401ELL101ML40S
ECK-A3A392KBP
440LD22-R
C317C104M5U5TA
ECA-1CHG470
ECA-1HHG100
5NK471KOBAM
EKZE250ELL681MJ20S
ELXZ250ELL221MH12D
EKZE100ELL222MK20S
ELXZ100ELL221MFB5D
Power Integrations
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RDR-142 35 W, TOP258PN Dual Output Supply
Complete Assembly (custom)
49
50
51
52
53
54
1
1
1
1
1
1
U1
U2
U3
VR1
VR2
VR3
TOPSwitch-HX, DIP-8B
Optocoupler, 80 V, CTR 80-160%, 4-DIP
2.495 V Shunt Regulator IC, 2%, 0 to 70C, TO-92
200 V, 600 W, 5%, TVS, DO204AC (DO-15)
20 V, 5%, 500 mW, DO-35
8.2 V, 500 mW, 2%, DO-35
07-Aug-14
TP07074
32/07 TR.RDK-142
019-4967-00R
SNX R1359
TOP258PN
PS2501-1-H-A
TL431CLPG
P6KE200ARLG
1N5250B
BZX55B8V2
Ice Components
Magtel
Precision Inc.
Santronics
Power Integrations
NEC
On Semi
On Semi
Microsemi
Vishay
Note – Parts listed above are RoHS compliant
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Page 12 of 43
07-Aug-14
RDR-142 35 W, TOP258PN Dual Output Supply
6 Transformer Specification
6.1
Electrical Diagram
Figure 4 – Transformer Electrical Diagram.
6.2
Electrical Specifications
Electrical Strength
Primary Inductance
Resonant Frequency
Primary Leakage Inductance
6.3
3000 VAC
1040 µH, ±10%
1000 kHz (Min.)
20 µH (Max.)
Materials
Item
[1]
[2]
[3]
[4]
[5]
[6]
[7]
[8]
[9]
[10]
[11]
[12]
1 second, 60 Hz, from pins 2, 3, 4, 5, 6 to pins 7, 9, 11.
Pins 2-4, all other windings open, measured at 100 kHz,
0.4 VRMS.
Pins 2-4, all other windings open.
Pins 2-4, with Pins 7-9 shorted, measured at 100 kHz,
0.4 VRMS.
Description
2
Core: EER28 gapped for ALG of 213 nH/T .
Bobbin: EER28, Horizontal 12 pins (6/6), YC-2806-5.
Magnet Wire: #27 AWG, double coated.
Magnet Wire: #26 AWG, double coated.
Tape: 3M Polyester Film, 2.0 mils thick, 16.0 mm wide.
Tape: 3M Polyester Film, 2.0 mils thick, 10.0 mm wide.
Copper Foil, 2 mils thick, 142 mm long, 8.5 mm wide. To be wrapped over with tape item [6].
Tape: 3M Polyester Film, 2.0 mils thick, 13.5 mm wide.
Bare Wire: #28 AWG.
Tape: 3M Polyester Film, 2.0 mils thick, 8.0 mm wide.
Varnish.
Polyester Web Margin Tape 3.1 mm wide.
Page 13 of 43
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RDR-142 35 W, TOP258PN Dual Output Supply
6.4
07-Aug-14
Transformer Build Diagram
2
3
11
7
9
11
5
6
3
4
margin tape
( 3.1 mm pre-molded margin bobbin)
Bobbin: EER28 (Horizontal, 12pins, 6/6), YC-2806-5)
Lp(2-4): 1.04mH +/- 5%
Tape: 3M Polyester Film – 2mil thick
2 x #28AWG connected to pin 7
Copper Foil – 2mil thick
2 x #28AWG connected to pin 11
8.5mm
13.5mm
142mm
Figure 5 – Transformer Build Diagram.
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Page 14 of 43
07-Aug-14
6.5
RDR-142 35 W, TOP258PN Dual Output Supply
Transformer Construction
General Note
WD1
1/2 Primary
Insulation
WD2
Bias
Insulation
WD3
st
1 Secondary
Insulation
nd
2
WD4
Secondary
Insulation
WD5
2/2 Primary
Insulation
Assembly
Finish
Page 15 of 43
Primary side of the bobbin orients to the left hand side. Place 3.1 mm margin tape
on both sides for all windings except WD1 due to built-in 3.1 mm margin of bobbin
[12]. Winding direction is clockwise.
Start on pin 4, wind 24 turns of item [3] from left to right with tight tension and bring
the wire across the bobbin to terminate at pin 3.
2 layers of tape item [5].
Start on pin 6, wind 7 turns bifilar of item [4] from left to right, spread the winding
evenly, and bring the wire across the bobbin to terminate on pin 5.
2 layers of tape item [5].
Start on pin 11, wind 3 turns of item [7] and terminate at pin 9.
1 layer of tape item [5].
Start on pin 7, wind 4 turns quadfilar of item [4] from right to left, spread the winding
evenly across the bobbin, and bring the wire back to the right to terminate on pin
11.
2 layers of tape item [5].
Start on pin 3, wind 23 turns of item [3] from left to right with tight tension, place 1
layer tape item [6], then wind another 23 turns of item [3] from right to left, also with
tight tension, and terminate at pin 2.
3 layers of tape item [5].
2
Grind the cores to get 1038 µH with ALG of 213 nH/T .
Secure the cores by wrapping around 2 halves of cores with item [10]. Dip varnish
uniformly in item [11].
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RDR-142 35 W, TOP258PN Dual Output Supply
07-Aug-14
7 Transformer Design Spreadsheet
ACDC_TOPSwitchHX_09
0607; Rev.1.2; Copyright
INPUT
Power Integrations 2007
ENTER APPLICATION VARIABLES
VACMIN
90
VACMAX
265
fL
50
VO
5.00
PO_AVG
35.00
PO_PEAK
n
0.80
Z
0.50
VB
12
tC
3.00
CIN
100.0
ENTER TOPSWITCH-HX VARIABLES
TOPSwitch-HX
INFO
OUTPUT
35.00
Info
100
TOP258PN
TOP258
PN
Chosen Device
KI
Power Out
UNIT
Volts
Volts
Hertz
Volts
Watts
Watts
%/100
Volts
mSeconds
uFarads
Universal /
Peak
35 W / 50
W
1.00
ILIMITMIN_EXT
ILIMITMAX_EXT
Frequency (F)=132kHz,
(H)=66kHz
1.534
1.766
H
Amps
Amps
H
fS
66000
Hertz
fSmin
59400
Hertz
fSmax
72600
Hertz
High Line Operating Mode
VOR
TOPSwitch_HX_090607: TOPSwitch-HX
Continuous/Discontinuous Flyback
Transformer Design Spreadsheet
RD-142
Minimum AC Input Voltage
Maximum AC Input Voltage
AC Mains Frequency
Output Voltage (main)
Average Output Power
Peak Output Power
Efficiency Estimate
Loss Allocation Factor
Ensure proper operation at no load.
Bridge Rectifier Conduction Time Estimate
Input Filter Capacitor
115 Doubled/230V
48W
External Ilimit reduction factor (KI=1.0 for
default ILIMIT, KI
