POWERINT EPR-91

Engineering Prototype Report for EP-91 –
12 W Power Supply using
TinySwitch®-III (TNY278P)
Title
Specification 85-265 VAC Input, 12 V, 1 A Output
Application
TinySwitch-III Reference Design (DAK-91)
Author
Power Integrations Applications Department
Document
Number
EPR-91
Date
7-February-06
Revision
1.1
Summary and Features
•
•
•
•
•
•
•
EcoSmart® – Meets all existing and proposed harmonized energy efficiency
standards including: CECP (China), CEC, EPA, AGO, European Commission
• No-load consumption 140 mW at 265 VAC (no bias winding required)
• > 75% active-mode efficiency (exceeds standards requirement of 71%)
BP/M capacitor value selects MOSFET current limit for greater design flexibility
Output overvoltage protection (OVP) using primary bias winding sensed
shutdown feature
Tightly toleranced I2f parameter (–10%, +12%) reduces system cost:
• Increases MOSFET and magnetics power delivery
• Reduces overload power, which lowers output diode and capacitor costs
Integrated TinySwitch-III Safety/Reliability features:
• Accurate (± 5%), auto-recovering, hysteretic thermal shutdown function
maintains safe PCB temperatures under all conditions
• Auto-restart protects against output short circuit and open loop fault
conditions
• > 3.2 mm creepage on package enables reliable operation in high humidity
and high pollution environments
Meets EN550022 and CISPR-22 Class B conducted EMI with >12 dBµV margin
Meets IEC61000-4-5 Class 3 AC line surge
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EP-91 12 V, 1 A, Universal Input Supply
7-Feb-2006
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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Page 2 of 36
7-Feb-2006
EP-91 12 V, 1 A, Universal Input Supply
Table Of Contents
1
2
3
4
Introduction................................................................................................................. 5
Power Supply Specification ........................................................................................ 6
Circuit Diagram........................................................................................................... 7
Circuit Description ...................................................................................................... 8
4.1
Input Rectification and Filtering ........................................................................... 8
4.2
TNY278P Operation ............................................................................................ 8
4.3
Output Rectification and Filtering ........................................................................ 9
4.4
Feedback and Output Voltage Regulation........................................................... 9
4.5
Output Overvoltage Shutdown ............................................................................ 9
4.6
EMI Design Aspects ............................................................................................ 9
4.7
Peak Primary Current Limit Selection................................................................ 10
4.8
UV Lockout........................................................................................................ 10
5 PCB Layout .............................................................................................................. 11
6 Bill Of Materials ........................................................................................................ 12
7 Transformer Specification......................................................................................... 13
7.1
Electrical Diagram ............................................................................................. 13
7.2
Electrical Specifications..................................................................................... 13
7.3
Materials............................................................................................................ 14
7.4
Transformer Build Diagram ............................................................................... 14
7.5
Transformer Construction.................................................................................. 15
8 Transformer Spreadsheet......................................................................................... 16
9 Performance Data .................................................................................................... 18
9.1
Efficiency........................................................................................................... 18
9.2
Active Mode CEC Measurement Data............................................................... 19
9.3
No-load Input Power (R8 not installed: no bias winding supplementation)........ 20
9.4
No-load Input Power (with R8 and bias winding supplementation) ................... 20
9.5
Available Standby Output Power....................................................................... 21
9.6
Regulation ......................................................................................................... 22
9.6.1
Load and Line ............................................................................................ 22
10 Thermal Performance ............................................................................................... 23
11 Waveforms............................................................................................................... 24
11.1 Drain Voltage and Current, Normal Operation .................................................. 24
11.2 Output Voltage Start-Up Profile......................................................................... 25
11.3 Drain Voltage and Current Start-Up Profile ....................................................... 25
11.4 Load Transient Response (75% to 100% Load Step) ....................................... 26
11.5 Output Ripple Measurements............................................................................ 27
11.5.1 Ripple Measurement Technique ................................................................ 27
11.5.2 Measurement Results ................................................................................ 28
11.6 Overvoltage Shutdown ...................................................................................... 28
12 Line Surge................................................................................................................ 29
13 Conducted EMI ........................................................................................................ 30
13.1 115 VAC, Full Load ........................................................................................... 30
13.2 230 VAC, Full Load ........................................................................................... 31
14 Audible Noise........................................................................................................... 32
Page 3 of 36
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EP-91 12 V, 1 A, Universal Input Supply
15
16
17
18
7-Feb-2006
Extended and Reduced Current Limit (ILIMIT) Operation ....................................... 33
TNY277 and TNY279 Operation in EP-91............................................................ 33
OVP Operation Verification .................................................................................. 34
Revision History.................................................................................................... 35
Important Note:
Although this board was designed to satisfy safety isolation requirements, it has not been
agency approved. Therefore, all testing should be performed using an isolation
transformer to provide the AC input to the power supply.
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Page 4 of 36
7-Feb-2006
EP-91 12 V, 1 A, Universal Input Supply
1 Introduction
This report describes a universal input, 12 V, 1 A flyback power supply using a TNY278P
device from the TinySwitch-III family of ICs. It contains the complete specification of the
power supply, a detailed circuit diagram, the entire bill of materials required to build the
supply, extensive documentation of the power transformer, along with test data and
oscillographs of the most important electrical waveforms. The board provides a number
of user configurable options which are designed to demonstrate the features and
flexibility of the TinySwitch-III family. These include easy adjustment of the device
current limit for increased output power or higher efficiency operation, and a latched
output overvoltage shutdown.
AC
AC
+
-
+
Figure 1 – EP-91 Populated Circuit Board Photographs.
Page 5 of 36
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EP-91 12 V, 1 A, Universal Input Supply
7-Feb-2006
2 Power Supply Specification
Description
Input
Voltage
Frequency
No-load Input Power (230 VAC)
No-load Input Power (230 VAC)
Output
Output Voltage
Output Ripple Voltage
Output Current
Total Output Power
Continuous Output Power
Overvoltage Shutdown
Efficiency
Full Load
Required average efficiency at
25, 50, 75 and 100 % of POUT
Symbol
Min
Typ
VIN
fLINE
85
47
50/60
VOUT
VRIPPLE
IOUT
11
POUT
VOV
12
15
η
ηCEC
12
Max
Units
Comment
265
64
0.15
0.05
VAC
Hz
W
W
2 Wire – no P.E.
13
100
V
mV
A
1
w/o UVLO resistor or bias winding
With bias winding support
± 8%
20 MHz bandwidth
W
V
With bias sense
75
%
Measured at POUT 25 oC
71.3
%
Per CEC / Energy Star STDs, with
TNY278 & standard current limit
18
Environmental
Conducted EMI
Meets CISPR22B / EN55022B
Designed to meet IEC950, UL1950
Class II
Safety
Surge (Differential)
1
kV
Surge (Common mode)
2
kV
Ambient Temperature
TAMB
0
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50
o
C
1.2/50 µs surge, IEC 1000-4-5,
Series Impedance:
Differential Mode: 2 Ω
Common Mode: 12 Ω
Free convection, sea level
Page 6 of 36
7-Feb-2006
EP-91 12 V, 1 A, Universal Input Supply
3 Circuit Diagram
Figure 2 – EP-91 Circuit Diagram.
Page 7 of 36
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EP-91 12 V, 1 A, Universal Input Supply
7-Feb-2006
4 Circuit Description
This flyback power supply was designed around the TNY278P (U1 in Figure 2). The
output voltage is sensed and fed back to U1 through optocoupler U2. That feedback is
used by U1 to maintain constant voltage (CV) regulation of the output.
4.1 Input Rectification and Filtering
Diodes D1–D4 rectify the AC input. Capacitors C1 and C2 filter the rectified DC.
Inductor L1, C1 and C2 form a pi filter that attenuates differential mode conducted EMI.
4.2 TNY278P Operation
The TNY278P device (U1) integrates an oscillator, a switch controller, startup and
protection circuitry, and a power MOSFET, all on one monolithic IC.
One side of the power transformer (T1) primary winding is connected to the positive leg
of C2, and the other side is connected to the DRAIN pin of U1. At the start of a switching
cycle, the controller turns the MOSFET on, and current ramps up in the primary winding,
which stores energy in the core of the transformer. When that current reaches the limit
threshold, the controller turns the MOSFET off. Due to the phasing of the transformer
windings and the orientation of the output diode, the stored energy then induces a
voltage across the secondary winding, which forward biases the output diode, and the
stored energy is delivered to the output capacitor. When the MOSFET turns off, the
leakage inductance of the transformer induces a voltage spike on the drain node. The
amplitude of that spike is limited by an RCD clamp network that consists of D5, C4 and
R2. Resistor R1 and VR1 provide hard clamping of the drain voltage, only conducting
during output overload. Resistor R2 also limits the reverse current that flows through D5
when the MOSFET turns on. This allows a slow, low-cost, glass passivated diode (with a
recovery time of ≤2 µs.) to be used for D5, which improves conducted EMI and efficiency.
Using ON/OFF control, U1 skips switching cycles to regulate the output voltage, based
on feedback to its EN/UV pin. The EN/UV pin current is sampled, just prior to each
switching cycle, to determine if that switching cycle should be enabled or disabled. If the
EN/UV pin current is <115 µA, the next switching cycle begins, and is terminated when
the current through the MOSFET reaches the internal current limit threshold. To evenly
spread switching cycles, preventing group pulsing, the EN pin threshold current is
modulated between 115 µA and 60 µA based on the state during the previous cycle. A
state-machine within the controller adjusts the MOSFET current limit threshold to one of
four levels, depending on the load being demanded from the supply. As the load on the
supply drops, the current limit threshold is reduced. This ensures that the effective
switching frequency stays above the audible range until the transformer flux density is
low. When the standard production technique of dip varnishing is used for the
transformer, audible noise is practically eliminated.
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Page 8 of 36
7-Feb-2006
EP-91 12 V, 1 A, Universal Input Supply
4.3 Output Rectification and Filtering
Diode D7 rectifies the output of T1. Output voltage ripple was minimized by using a low
ESR capacitor for C10 (see Section 6 for component part numbers and values). A post
filter (ferrite bead L2 and C11) attenuates the high frequency switching noise.
4.4 Feedback and Output Voltage Regulation
The supply’s output voltage regulation set point is set by the voltage that develops across
Zener diode VR3, R6 and the LED in opto-coupler U2. The value of R4 was calculated to
bias VR3 to about 0.5 mA when it goes into reverse avalanche conduction. This ensures
that it is operating close to its rated knee current. Resistor R6 limits the maximum current
during load transients. The values of R4 and R6 can both be varied slightly to fine-tune
the output regulation set point. When the output voltage rises above the set point, the
LED in U2 becomes forward biased. On the primary side, the photo-transistor of U2
turns on and draws current out of the EN/UV pin of U1. Just before the start of each
switching cycle, the controller checks the EN/UV pin current. If the current flowing out of
the EN/UV pin is greater than 115 µA, that switching cycle will be disabled. As switching
cycles are enabled and disabled, the output voltage is kept very close to the regulation
set point. For greater output voltage regulation accuracy, a reference IC such as a
TL431 can be used in place of VR3.
4.5 Output Overvoltage Shutdown
The TinySwitch-III family of ICs can detect overvoltage on the output of the supply and
latch off. This protects the load in an open feedback loop fault condition, such as the
failure of the optocoupler. Overvoltage on the output is detected through the BP/M pin
and the bias winding on the transformer. The bias winding voltage is determined by the
reflection of the output voltage through the turns ratio of the transformer. Therefore, an
overvoltage on the output will be reflected onto the bias winding. The overvoltage
threshold is the sum of the breakdown voltage of Zener diode VR2 and the BP/M pin
voltage (28 V + 5.8 V). If the output voltage becomes abnormally high, the voltage on the
bias winding will exceed the threshold voltage and excess current will flow into the BP/M
pin. The latching shutdown circuit is activated when current into the BP/M pin exceeds
5 mA. Resetting a latched shutdown requires removing the AC input from the supply
long enough to allow the input capacitors (C1 and C2) to discharge, and the BP/M pin
voltage to drop below 2 V. Resistors R7 and R3 provide additional filtering of the bias
voltage, with R3 also limiting the maximum current into the BYPASS pin in an OV
condition
4.6 EMI Design Aspects
An input pi filter (C1, L1 and C2) attenuates conducted, differential mode EMI noise.
Shielding techniques (E-Shield™) were used in the construction of T1 to reduce common
mode EMI displacement currents. Resistor R2 and capacitor C4 dampen out some of the
high frequency ringing that occurs when the MOSFET turns off. When combined with the
IC’s frequency jitter function, these techniques produce excellent conducted and radiated
EMI performance (see Section 12 of this report).
Page 9 of 36
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EP-91 12 V, 1 A, Universal Input Supply
7-Feb-2006
4.7 Peak Primary Current Limit Selection
The value of the capacitor installed on the BP/M pin allows the current limit of U1 to be
selected. The power supply designer can change the current limit of the MOSFET by
simply changing the capacitance value connected to the BP/M pin (see the TinySwitch-III
data sheet for more details).
Installing a 0.1 µF capacitor on the BP/M pin selects the standard current
limit of the IC, and is the normal choice for enclosed adapter applications.
Installing a 1 µF capacitor on the BP/M pin reduces the MOSFET current
limit, which lowers conduction losses and improves efficiency (at the
expense of reducing the maximum power capability of the IC).
A 10 µF capacitor on the BP/M pin will raise the MOSFET current limit and
extend the power capability of the IC (for higher power applications that do
not have the thermal constraints of an enclosed adapter, or to supply
short-duration, peak load demands).
The EP91 demonstration board comes with a 0.1 µF capacitor installed as C7, which
causes U1 to select the standard current limit specified in the TinySwitch-III data sheet. If
C7 were replaced by a 1 µF capacitor (C8 in the BOM, section 6), the current limit of U1
will be the same as the standard current limit for a TNY277 device. If a 10 µF capacitor is
installed, the current limit of U1 will be the same as the standard current limit for a
TNY279 device. The flexibility of this option enables the designer to do three things.
First, it allows the designer to measure the effect of switching to an adjacent device
without actually removing and replacing the IC. Second, it allows a larger device to be
used with a lower current limit, for higher efficiency. Third, it allows a smaller device to
be used with a higher current limit in a design when higher power is not required on a
continual basis, which effectively lowers the cost of the supply.
4.8 UV Lockout
The EP91 circuit board has a location where an optional under-voltage (UV) lockout
detection resistor (R5) can be installed. When installed, MOSFET switching is disabled
at startup until current into the EN/UV pin exceeds 25 µA. This allows the designer to set
the input voltage at which MOSFET switching will be enabled by choosing the value of
R5. For example, a value of 3.6 MΩ requires an input voltage of 65 VAC (92 VDC across
C2) before the current into the EN/UV pin exceeds 25 µA. The UV detect function also
prevents the output of the power supply from glitching (trying to restart) after output
regulation is lost (during shutdown), by disabling MOSFET switching until the input
voltage rises above the under-voltage lockout threshold.
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Page 10 of 36
7-Feb-2006
EP-91 12 V, 1 A, Universal Input Supply
5 PCB Layout
Figure 3 – Printed Circuit Board Layout (3.2 × 1.8 inches).
Page 11 of 36
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EP-91 12 V, 1 A, Universal Input Supply
7-Feb-2006
6 Bill Of Materials
Value
Description
Mfg Part Number
Mfg
1
Part
Ref
C1
6.8 µF
6.8 µF, 400 V, Electrolytic, (10 x 16)
EKXG401ELL6R8MJ16S
2
1
C2
22 µF
EKMX401ELL220ML20S
3
1
C4
10 nF
22 µF, 400 V, Electrolytic, Low
ESR, 901 mΩ, (16 x 20)
10 nF, 1 kV, Disc Ceramic
5HKMS10
United
Chemi-Con
United
Chemi-Con
Vishay
4
1
C5
2.2 nF
2.2 nF, Ceramic, Y1
440LD22
Vishay
5
1
C7
100 nF
100 nF, 50 V, Ceramic, X7R
6
2
1 µF
7
1
C6,
C8*
C9*
8
1
C10
1000 µF
9
1
C11
100 µF
10
4
1N4007
1N4007
Epcos/
Panasonic
United
Chemi-Con
United
Chemi-Con
United
Chemi-Con
United
Chemi-Con
Vishay
11
1
D1 D2
D3 D4
D5
1 µF, 50 V, Electrolytic, Gen.
Purpose, (5 x 11)
10 µF, 50 V, Electrolytic, Gen.
Purpose, (5 x 11)
1000 µF, 25 V, Electrolytic, Very
Low ESR, 21 mΩ, (12.5 x 20)
100 µF, 25 V, Electrolytic, Very Low
ESR, 130 mΩ, (6.3 x 11)
1000 V, 1 A, Rectifier, DO-41
B37987F5104K000 / ECUS1H104KBB
EKMG500ELL1R0ME11D
1N4007GP
Vishay
12
1
D6
UF4003
UF4003
Vishay
13
1
D7
BYV28-200
BYV28-200
Vishay
14
15
16
17
18
19
20
1
2
1
1
1
1
1
F1
J1 J4
J2
J3
JP1
L1
L2
3.15 A
3701315041
5011
5012
5010
KSW24W-0100
HTB2-102-281
2743004112
Wickman
Keystone
Keystone
Keystone
OK Indust.
CUI
Fair-Rite
21
22
23
24
25
26
27
28
29
30
1
1
1
1
1
1
1
1
1
1
R1
R2
R3
R4
R5*
R6
R7
R8*
RV1
T1
1 kΩ
100 Ω
47 Ω
2 kΩ
3.6 MΩ
390 Ω
20 Ω
21 kΩ
275 VAC
EE25 Core
CFR-25JB-1K0
CFR-25JB-100R
CFR-12JB-47R
CFR-12JB-2K0
CFR-50JB-3M6
CFR-12JB-390R
CFR-25JB-20R
MFR-25FBF-21K0
V275LA10
YW-360-02B
Item
Qty
1
10 µF
1N4007GP
1 mH
Ferrite Bead
1000 V, 1 A, Rectifier, Glass
Passivated, 2 us, DO-41
200 V, 1 A, Ultrafast Recovery,
50 ns, DO-41
200 V, 3.5 A, Ultrafast Recovery,
25 ns, SOD64
3.15 A, 250V,Fast, TR5
Test Point, Black, Thru-hole mount
Test Point, White, Thru-hole mount
Test Point, Red, Thru-hole mount
Wire Jumper, Insulated, 24 AWG
1mH, 350 mA
3.5 mm x 7.6 mm, 75 Ω at 25 MHz,
22 AWG hole, Ferrite Bead
1 kΩ, 5%, 1/4 W, Carbon Film
100 Ω, 5%, 1/4 W, Carbon Film
47 Ω, 5%, 1/8 W, Carbon Film
2 kΩ, 5%, 1/8 W, Carbon Film
3.6 MΩ, 5%, 1/2 W, Carbon Film
390 Ω, 5%, 1/8 W, Carbon Film
20 Ω, 5%, 1/4 W, Carbon Film
21 kΩ, 1%, 1/4 W, Metal Film
275 V, 45 J, 10 mm, Radial
Bobbin, EE25, Vertical, 10 pins
EKMG500ELL100ME11D
EKZE250ELL102MK20S
EKZE250ELL101MF11D
31
1
U1
TNY278P
TinySwitch-III, TNY278P, DIP-8C
32
1
U2
PC817A
33
1
VR1
P6KE150A
P6KE150A
34
1
VR2
1N5255B
Optocoupler, 35 V, CTR 80-160%,
4-DIP
150 V, 5 W, 5%, TVS, DO204AC
(DO-15)
28 V, 500 mW, 5%, DO-35
Yageo
Yageo
Yageo
Yageo
Yageo
Yageo
Yageo
Yageo
Littlefuse
Yih-Hwa
Enterprises
Santronics
LiShin
CWS
Hical
Power
Integrations
Isocom,
Sharp
Vishay
1N5255B
Microsemi
35
1
VR3
BZX79-B11
11 V, 500 mW, 2%, DO-35
BZX79-B11
Vishay
Complete Assembly
SNX-1380
LSPA20544
CWS-T1-EP91
SIL6038
TNY278P
ISP817A, PC817X1
* Optional components
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Page 12 of 36
7-Feb-2006
EP-91 12 V, 1 A, Universal Input Supply
7 Transformer Specification
7.1
Electrical Diagram
NC
Cancellation
14T # 30 AWG X2
WDG # 1
1
Primary
WDG # 2
56T # 30 AWG
8
3
Bias
WDG # 3
WDG # 4
Secondary WDG # 5
7T # 26 T.I.W
4
6T # 26 AWG X3
6
2
Bias
6T # 26 AWG X3
5
Figure 4 – Transformer Electrical Diagram.
7.2
Electrical Specifications
Electrical Strength
Primary Inductance
Resonant Frequency
Primary Leakage Inductance
Page 13 of 36
1 second, 60 Hz, from Pins 1-5 to Pins 6-10
Pins 1-3, all other windings open, measured at
100 kHz, 0.4 V RMS
Pins 1-3, all other windings open
Pins 1-3, with Pins 6-8 shorted, measured at
100 kHz, 0.4 V RMS
3000 VAC
1050 µH, ±10%
500 kHz (Min.)
50 µH (Max.)
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EP-91 12 V, 1 A, Universal Input Supply
7.3
Materials
Item
[1]
[2]
[3]
[4]
[5]
[6]
[7]
[8]
[9]
[10]
7.4
7-Feb-2006
Description
2
Core: PC40EE25-Z, TDK or equivalent Gapped for AL of 335 nH/T
Bobbin: EE25, Vertical, 10 pin – Yih-Hwa part # YW-360-02B
Magnet Wire: #30 AWG
Magnet Wire: #26 AWG
Triple Insulated Wire: #26 AWG.
Tape: 3M # 44 Polyester web. 2.0 mm wide
Tape: 3M 1298 Polyester Film, 2.0 mils thick, 8.6 mm wide
Tape: 3M 1298 Polyester Film, 2.0 mils thick, 10.7 mm wide
Tape: 3M 1298 Polyester Film, 2.0 mils thick, 4.0 mm wide
Varnish (applied by dipping only, not vacuum impregnation)
Transformer Build Diagram
6
8
2 mm
1 layer of tape
5
2
2 mm
4
Margin
1
Bias Winding
Tape
Primary Winding
3
1 layer of tape
Cancellation Winding
1
No Connect
Figure 5 – Transformer Build Diagram.
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Page 14 of 36
7-Feb-2006
7.5
EP-91 12 V, 1 A, Universal Input Supply
Transformer Construction
Bobbin Set Up
Orientation
Margin Tape
WD1
Cancellation Winding
Insulation
WD#2
Primary winding
Insulation
WD #3
Bias Winding
Insulation
WD #4
Bias Winding
Insulation
Margin Tape
WD #5
Secondary Winding
Outer Insulation
Core Assembly
Varnish
Page 15 of 36
Set up the bobbin with its pins oriented to the left hand side.
Apply 2.0 mm margin at the pin side of bobbin using item [6]. Match
combined height of shield, primary, and bias windings.
Start at Pin 1. Wind 14 bifilar turns of item [3] from left to right. Wind with
tight tension across entire bobbin evenly. Cut the ends of the bifilar and
leave floating.
1 Layer of tape [7] for insulation.
Start at pin 3. Wind 28 turns of item [3] from left to right. Apply 1 Layer of
tape [7] for insulation. Wind another 28 turns from right to left. Wind with
tight tension across entire bobbin evenly. Finish at Pin 1.
1 Layer of tape [7] for insulation.
Start at Pin 4, wind 6 trifilar turns of item [5]. Wind from left to right with
tight tension. Wind uniformly, in a single layer across entire width of
bobbin. Finish on Pin 2.
1 Layer of tape [7] for insulation.
Start at Pin 2, wind 6 trifilar turns of item [5] from left to right with tight
tension. Wind uniformly, in a single layer across entire width of bobbin.
Finish on Pin 5.
1 Layer of tape [8] for insulation.
Apply 2.0 mm margin at the pin side of bobbin using item [6]. Match
combined height of secondary windings.
Start at Pin 8, wind 7 turns of item [5] from left to right. Wind uniformly, in
a single layer across entire bobbin evenly. Finish on Pin 6.
3 Layers of tape [8] for insulation.
Assemble and secure core halves using item [1] and item [9]
Dip varnish using item [10] (do not vacuum impregnate)
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EP-91 12 V, 1 A, Universal Input Supply
7-Feb-2006
8 Transformer Spreadsheet
ACDC_TinySwitch-III
INPUT
_011906; Rev.0.27;
Copyright Power
Integrations 2006
ENTER APPLICATION VARIABLES
VACMIN
85
VACMAX
265
fL
50
VO
12.00
IO
1.00
Power
n
0.71
Z
0.50
tC
CIN
INFO
OUTPUT
EP91 - 12 V, 1 A, Universal Input
Minimum AC Input Voltage
Maximum AC Input Voltage
AC Mains Frequency
Output Voltage (at continuous power)
Power Supply Output Current (corresponding to
peak power)
12 Watts
Continuous Output Power
Efficiency Estimate at output terminals. Unter 0.7 if
no better data available
Z Factor. Ratio of secondary side losses to the total
losses in the power supply. Use 0.5 if no better data
available
mSeconds Bridge Rectifier Conduction Time Estimate
28.8 uFarads
Input Capacitance
TNY278
User defined TinySwitch-III
Standard
Current Limit
Enter "RED" for reduced current limit (sealed
adapters), "STD" for standard current limt or "INC"
for increased current limit (peak or higher power
applications)
Minimum Current Limit
TNY278
ILIMITMIN
ILIMITTYP
ILIMITMAX
fSmin
I^2fmin
0.512
0.550
0.588
124000
35.937
VOR
101.00
Amps
Amps
Amps
Hertz
A^2kHz
101 Volts
VDS
VD
KP
10 Volts
0.7 Volts
0.60
KP_TRANSIENT
0.38
ENTER BIAS WINDING VARIABLES
VB
NB
VZOV
UVLO VARIABLES
V_UV_TARGET
ACDC_TinySwitch-III_011906_Rev0-27.xls;
TinySwitch-III Continuous/Discontinuous
Flyback Transformer Design Spreadsheet
Volts
Volts
Hertz
Volts
Amps
3.00
28.80
ENTER TinySwitch-III VARIABLES
TinySwitch-III
TNY278
Chosen Device
STD
Chose Configuration
UNIT
92
V_UV_ACTUAL
RUV_IDEAL
RUV_ACTUAL
Transient Ripple to Peak Current Ratio. Ensure
KP_TRANSIENT > 0.25
22.00 Volts
12.13
28.00 Volts
Bias Winding Voltage
Bias Winding Number of Turns
Over Voltage Protection zener diode.
92.00 Volts
Target under-voltage threshold, above which the
power supply with start
Typical start-up voltage based on standard value of
RUV_ACTUAL
Calculated value for UV Lockout resistor
Closest standard value of resistor to RUV_IDEAL
92.20 Volts
3.59 Mohms
3.60 Mohms
ENTER TRANSFORMER CORE/CONSTRUCTION VARIABLES
Core Type
EE25
EE25
Core
EE25
Bobbin
EE25_BOBBIN
AE
0.404
LE
7.34
AL
1420
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Maximum Current Limit
Minimum Device Switching Frequency
I^2f (product of current limit squared and frequency
is trimmed for tighter tolerance)
Reflected Output Voltage (VOR < 135 V
Recommended)
TinySwitch-III on-state Drain to Source Voltage
Output Winding Diode Forward Voltage Drop
Ripple to Peak Current Ratio (KP < 6)
P/N:
P/N:
cm^2
cm
nH/T^2
User-Selected transformer core
PC40EE25-Z
EE25_BOBBIN
Core Effective Cross Sectional Area
Core Effective Path Length
Ungapped Core Effective Inductance
Page 16 of 36
7-Feb-2006
EP-91 12 V, 1 A, Universal Input Supply
BW
M
1.00
L
NS
2.00
7
10.2 mm
1 mm
Bobbin Physical Winding Width
Safety Margin Width (Half the Primary to Secondary
Creepage Distance)
Number of Primary Layers
Number of Secondary Turns
2
7
DC INPUT VOLTAGE PARAMETERS
VMIN
VMAX
79 Volts
375 Volts
Minimum DC Input Voltage
Maximum DC Input Voltage
CURRENT WAVEFORM SHAPE PARAMETERS
DMAX
0.59
Duty Ratio at full load, minimum primary inductance
and minimum input voltage
Average Primary Current
Minimum Peak Primary Current
Primary Ripple Current
Primary RMS Current
IAVG
IP
IR
IRMS
0.24
0.5120
0.3075
0.33
Amps
Amps
Amps
Amps
TRANSFORMER PRIMARY DESIGN PARAMETERS
LP
1050 uHenries
LP_TOLERANCE
NP
ALG
BM
10
56
339
2745
10.00
BAC
824
ur
LG
BWE
OD
2053
0.11
16.4
0.295
INS
0.05
Typical Primary Inductance. +/- 10% to ensure a
minimum primary inductance of 954 uH
%
Primary inductance tolerance
Primary Winding Number of Turns
nH/T^2
Gapped Core Effective Inductance
Gauss
Maximum Operating Flux Density, BM<3000 is
recommended
Gauss
AC Flux Density for Core Loss Curves (0.5 X Peak
to Peak)
Relative Permeability of Ungapped Core
mm
Gap Length (Lg > 0.1 mm)
mm
Effective Bobbin Width
mm
Maximum Primary Wire Diameter including
insulation
mm
Estimated Total Insulation Thickness (= 2 * film
thickness)
mm
Bare conductor diameter
AWG
Primary Wire Gauge (Rounded to next smaller
standard AWG value)
Cmils
Bare conductor effective area in circular mils
Cmils/Amp Primary Winding Current Capacity (200 < CMA <
500)
DIA
AWG
0.243
31
CM
CMA
81
247
TRANSFORMER SECONDARY DESIGN PARAMETERS
Lumped parameters
ISP
ISRMS
IRIPPLE
CMS
AWGS
4.07
2.15
1.90
430
23
VOLTAGE STRESS PARAMETERS
VDRAIN
607 Volts
PIVS
Page 17 of 36
Amps
Amps
Amps
Cmils
AWG
59 Volts
Peak Secondary Current
Secondary RMS Current
Output Capacitor RMS Ripple Current
Secondary Bare Conductor minimum circular mils
Secondary Wire Gauge (Rounded up to next larger
standard AWG value)
Maximum Drain Voltage Estimate (Assumes 20%
zener clamp tolerance and an additional 10%
temperature tolerance)
Output Rectifier Maximum Peak Inverse Voltage
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EP-91 12 V, 1 A, Universal Input Supply
7-Feb-2006
9 Performance Data
The ON/OFF control scheme employed by TinySwitch-III yields virtually constant
efficiency across the 25% to 100% load range required for compliance with EPA, CEC,
CECP and AGO energy efficiency standards for external power supplies (EPS). Even at
loads below 10% of the supply’s full rated output power, efficiency remains above 65%,
providing excellent standby performance for applications that require it. This performance
is automatic with ON/OFF control. There are no special burst modes that require the
designer to consider specific thresholds within the load range in order to achieve
compliance with global energy efficiency standards.
All measurements performed at room temperature, 60 Hz input frequency.
Efficiency
90%
85%
80%
Efficiency (%)
9.1
75%
CEC/ENERGY STAR EPS Requirement
70%
85 VAC
65%
115 VAC
230 VAC
60%
265 VAC
55%
50%
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
Output Current (A)
Figure 6 – Efficiency vs. Output Current, Room Temperature, 60 Hz.
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Page 18 of 36
7-Feb-2006
EP-91 12 V, 1 A, Universal Input Supply
9.2 Active Mode CEC Measurement Data
In the state of California, after July 1, 2006, all single-output EPS adapters – including
those sold with the products they power – must meet the California Energy Commission
(CEC) requirement for minimum active-mode efficiency and no-load input power
consumption. Minimum active-mode efficiency is defined as the average efficiency at 25,
50, 75 and 100% of rated output power printed on the nameplate of the supply:
Nameplate
Output (PO)
Minimum Efficiency in Active Mode
of Operation
<1W
≥ 1 W to ≤ 49 W
> 49 W
0.49 × PO
0.09 × ln (PO) + 0.49 [ln = natural log]
0.84 W
For adapters that are single input voltage only, the measurements are to be made at the
nominal rated input voltage (115 VAC or 230 VAC). For universal input adapters, the
measurements are to be made at both nominal input voltages (115 VAC and 230 VAC).
To comply with the standard, the average of the four efficiency measurements must be
greater than or equal to the efficiency specified by the standard.
Percent of Full
Load
25
50
75
100
Average
Required CEC
minimum average
efficiency (%)
Efficiency (%)
115 VAC
230 VAC
75
78.5
78.8
78
77.6
74.5
78.8
78.5
79.1
77.7
71.3
From these results it is apparent that the efficiency of this design easily exceeds the
required 71.3 %. More states within the USA, and many other countries around the world
are adopting similar energy efficiency standards (based on the original Energy Star
standard). For the latest, up-to-date information on energy efficiency regulations, please
visit the PI Green Room, at:
http://www.powerint.com/greenroom/regulations.htm
Page 19 of 36
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EP-91 12 V, 1 A, Universal Input Supply
9.3
7-Feb-2006
No-load Input Power (R8 not installed: no bias winding supplementation)
0.14
Input Power (Watts)
0.12
0.1
0.08
0.06
0.04
0.02
0
85
105
125
145
165
185
205
225
245
265
Input VAC
Figure 7 – No-load Input Power vs. Input Line Voltage, Room Temperature, 60 Hz.
9.4
No-load Input Power (with R8 and bias winding supplementation)
0.045
0.04
Input Power (Watts)
0.035
0.03
0.025
0.02
0.015
0.01
0.005
0
85
105
125
145
165
185
205
225
245
265
Input Voltage (VAC)
Figure 8 – No-load Input Power vs. Input Line Voltage, Room Temperature, 60 Hz, with Bias Winding.
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Page 20 of 36
7-Feb-2006
EP-91 12 V, 1 A, Universal Input Supply
9.5 Available Standby Output Power
The chart below shows the available output power versus line voltage at input power
consumption levels of 1, 2 and 3 watts (respectively). Again, this performance illustrates
the value of ON/OFF control, as it automatically maintains a high efficiency, even during
very light loading. This simplifies complying with standby requirements that specify that a
fair amount of power be available to the load at low input power consumption levels. The
TinySwitch-III ON/OFF control scheme maximizes the amount of output power available
to the load in standby operation when the allowable input power is fixed at a low value.
This simplifies the design of products such as printers, set-top boxes, DVD players, etc.
that must meet stringent standby power consumption requirements.
3
Pin=1 W
Pin=2 W
Output Power (W)
2.5
2.2 W for 3 W input at 230 VAC
Pin=3 W
2
1.4 W for 2 W input at 230 VAC
1.5
1
0.65 W for 1 W input at 230 VAC
0.5
0
85
105
125
145
165
185
205
225
245
265
285
Input Voltage (VAC)
Figure 9 – Available Output Power for 1, 2 and 3 Watts of Input Power.
Page 21 of 36
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EP-91 12 V, 1 A, Universal Input Supply
9.6
7-Feb-2006
Regulation
9.6.1 Load and Line
13
85 VAC
12.8
115 VAC
Output Voltage (V)
12.6
230 VAC
12.4
265 VAC
12.2
12
11.8
11.6
11.4
11.2
11
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
Output Current (A)
Figure 10 – Load and Line Regulation, Room Temperature.
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Page 22 of 36
7-Feb-2006
EP-91 12 V, 1 A, Universal Input Supply
10 Thermal Performance
Temperature measurements of key components were taken using T-type thermocouples.
The thermocouples were soldered directly to a SOURCE pin of the TNY278P device and
to the cathode of the output rectifier. The thermocouples were glued to the output
capacitor and to the external core and winding surfaces of transformer T1.
The unit was sealed inside a large box to eliminate any air currents. The box was placed
inside a thermal chamber. The ambient temperature within the large box was raised to
50 °C. The unit was then operated at full load and the temperature measurements were
taken after they stabilized for 1 hour at 50 °C.
Temperature (°C)
Item
85 VAC
*
265 VAC
*
Ambient
50
50
TNY278P (U1)
96.1
92.8
Transformer (T1)
77.8
80
Output Rectifier (D7)
101
100
Output Capacitor (C10)
68.2
66.8
*To simulate operation inside sealed enclosure at 40 °C external ambient.
These results show that all key components have an acceptable rise in temperature.
85 VAC, 12 W Load, 22 °C Ambient
Figure 11 – Infrared Thermograph of Open Frame Operation, at Room Temperature.
Page 23 of 36
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EP-91 12 V, 1 A, Universal Input Supply
7-Feb-2006
11 Waveforms
11.1 Drain Voltage and Current, Normal Operation
Figure 12 – 115 VAC, Full Load.
Upper: IDRAIN, 0.1 A / div.
Lower: VDRAIN, 50 V, 500 ns / div.
Figure 13 – 230 VAC, Full Load.
Upper: IDRAIN, 0.1 A / div.
Lower: VDRAIN, 100 V / div.
Figure 14 – 115 VAC, Full Load.
VDRAIN, 50 V, 20 µs / div.
Figure 15 – 230 VAC, Full Load.
VDRAIN, 100 V, 20 µs / div.
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Page 24 of 36
7-Feb-2006
EP-91 12 V, 1 A, Universal Input Supply
11.2 Output Voltage Start-Up Profile
Start-up into full resistive load and no-load were both verified. A 12 Ω resistor was used
for the load, to maintain 1 A under steady-state conditions.
Figure 16 – Start-Up Profile, 115 VAC.
Fast trace is no-load rise time
Slower trace is maximum load (12 Ω)
2 V, 5 ms / div.
Figure 17 – Start-Up Profile, 230 VAC.
Fast trace is no-load rise time
Slower trace is maximum load (12 Ω)
2 V, 5 ms / div.
11.3 Drain Voltage and Current Start-Up Profile
Figure 18 – 90 VAC Input and Maximum Load.
Upper: VDRAIN, 100 V & 100 µs / div.
Lower: IDRAIN, 0.5 A / div.
Page 25 of 36
Figure 19 – 265 VAC Input and Maximum Load.
Upper: VDRAIN, 200 V & 100 µs / div.
Lower: IDRAIN, 0.5 A / div.
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EP-91 12 V, 1 A, Universal Input Supply
7-Feb-2006
11.4 Load Transient Response (75% to 100% Load Step)
Figure 20 – Transient Response, 115 VAC,
50-100-50% Load Step.
Upper: VOUT 50 mV/div.
Lower: IOUT 0.5 A, 1 ms / div.
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Figure 21 – Transient Response, 230 VAC,
50-100-50% Load Step.
Upper: VOUT 50 mV/div.
Lower: IOUT 0.5 A, 1 ms / div.
Page 26 of 36
7-Feb-2006
EP-91 12 V, 1 A, Universal Input Supply
11.5 Output Ripple Measurements
11.5.1 Ripple Measurement Technique
A modified oscilloscope test probe was used to take output ripple measurements, in order
to reduce the pickup of spurious signals. Using the probe adapter pictured in Figure 22,
the output ripple was measured with a 1 µF electrolytic, and a 0.1 µF ceramic capacitor
connected as shown.
Probe Ground
Probe Tip
Figure 22 – Oscilloscope Probe Prepared for Ripple Measurement (End Cap and Ground Lead Removed).
Page 27 of 36
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EP-91 12 V, 1 A, Universal Input Supply
7-Feb-2006
11.5.2 Measurement Results
Figure 23 – Ripple, 85 VAC, Full Load.
20 µs, 50 mV / div.
Figure 24 – Ripple, 115 VAC, Full Load.
20 µs, 50 mV / div.
11.6 Overvoltage Shutdown
Figure 25 – Overvoltage Shutdown.
265 VAC, No Load.
50 ms, 5 V / div.
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Figure 26 – Overvoltage Shutdown.
265 VAC, Full Load.
50 ms, 5 V / div.
Page 28 of 36
7-Feb-2006
EP-91 12 V, 1 A, Universal Input Supply
12 Line Surge
Differential input line surge (1.2/50 µs) testing was completed on a single test unit to
IEC61000-4-5. Input voltage was set at 230 VAC / 60 Hz. Output was loaded at full load
and operation was verified following each surge event.
Surge
Voltage
1 kV
Differential
2 kV
Common
Mode
Phase Angle
Generator
Impedance
Number of Strikes
Test Result
90˚
2Ω
10
PASS
90˚
12 Ω
10
PASS
Unit passed under all test conditions.
Page 29 of 36
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EP-91 12 V, 1 A, Universal Input Supply
7-Feb-2006
13 Conducted EMI
Conducted emissions tests were performed at 115 VAC and 230 VAC at full load (12 V,
1 A). Measurements were taken with an Artificial Hand connected and a floating DC
output load resistor. A DC output cable was included.
Composite EN55022B / CISPR22B conducted limits are shown. In all cases there was
excellent (>10 dB) margin.
13.1 115 VAC, Full Load
Line
Neutral
Artificial Hand Connected to Output Return
Artificial Hand Connected to Output Return
Output Floating
Output Floating
Figure 27
– Conducted EMI at 115 VAC.
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Page 30 of 36
7-Feb-2006
EP-91 12 V, 1 A, Universal Input Supply
13.2 230 VAC, Full Load
Line
Neutral
Artificial Hand Connected to Output Return
Artificial Hand Connected to Output Return
Output Floating
Output Floating
Figure 28
Page 31 of 36
– Conducted EMI at 230 VAC.
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EP-91 12 V, 1 A, Universal Input Supply
7-Feb-2006
14 Audible Noise
An open-frame (no enclosure) unit was tested with an Audio Precision Analyzer, using a
microphone positioned one inch from the core of transformer T1. The test was done with
the unit in an acoustically isolated and dampened chamber. The load was adjusted until
a maximum reading was obtained.
35 dBrA is considered the acceptable limit for frequencies below 18 kHz. An enclosure
will typically further reduce measurable acoustic noise levels by an additional 10 dBrA.
Audio Precision
08/17/05 15:04:17
Audio Precision
+80
+80
+70
+70
+60
+60
+50
+50
+40
d
B
r
08/17/05 15:11:39
+40
d
B
r
+30
+20
+30
+20
A
A
+10
+10
+0
+0
-10
-10
-20
-20
-30
0
2k
4k
6k
8k
10k
12k
14k
16k
18k
20k
-30
0
22k
2k
4k
6k
8k
10k
Hz
Color
Line Style
Thick
Data
Axis
Green
Solid
1
Fft.Ch.1 Ampl
Left
12k
14k
16k
18k
Color
Line Style
Thick
Data
Axis
Green
Solid
1
Fft.Ch.1 Am pl
Left
Arts_audionoise1.at2
22k
Arts_audionoise1.at2
Figure 29 – Audible Noise VIN = 120 VAC;
IOUT = 350 mA.
Figure 30 – Audible Noise VIN = 120 VAC;
IOUT = 1 A.
Audio
Audio Precision
08/17/05
+80
+80
+70
+70
+60
+60
+50
+50
+40
d
B
r
20k
Hz
08/17/05 15:09:38
+40
d
B
r
+30
+20
+30
+20
A
A
+10
+10
+0
+0
-10
-10
-20
-20
-30
0
2k
4k
6k
8k
10k
12k
14k
16k
18k
20k
22k
-30
0
2k
4k
6k
8k
Hz
12k
14k
16k
18k
20k
22k
Hz
Color
Line Style
Thick
Data
Axis
Color
Line Style
Thick
Data
Axis
Green
Solid
1
Fft.Ch.1 Ampl
Left
Green
Solid
1
Fft.Ch.1 Am pl
Left
Arts_audionoise1.at2
Figure 31 – Audible Noise VIN = 230 VAC;
IOUT =1 A.
10k
Arts _audionoise1.at2
Figure 32 – Audible Noise VIN = 230 VAC;
IOUT =1.2 A.
Note: Shaded area obscured due to ambient noise.
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Page 32 of 36
7-Feb-2006
EP-91 12 V, 1 A, Universal Input Supply
15 Extended and Reduced Current Limit (ILIMIT) Operation
Additional capacitors (C8 and C9 on the BOM in Section 6) have been included in the
DAK-91 kit for the convenience of trying out the ILIMIT+1 and ILIMIT–1 operation of TNY278
in the EP-91 reference board. When C7 (0.1 µF) is replaced with a 10 µF capacitor (C9),
the TNY278 will operate in the ILIMIT+1 mode, which increases the maximum primary
current limit from the standard maximum limit of 0.55 A to 0.65 A (equal to that of a
TNY279). This allows a TNY278 to deliver from 15% to 25% more output power
(depending on the output voltage and current).
CAUTION: Because EP-91 was designed for standard ILIMIT operation, It should not be
loaded with more than 1.25 A at an elevated temperature for very long (a few minutes)
when verifying the performance of TNY278 in the ILIMIT+1 mode, since the other power
components (transformer, input bulk capacitors, output diode, output capacitors and
primary clamp network) are not sized for sustained operation at more than 12 W.
When C7 is replaced with a 1 µF capacitor (C8), the TNY278 will operate in the ILIMIT–1
mode, which reduces the maximum current limit from the standard maximum limit of
0.55 A to 0.45 A (equal to that of a TNY277). Although this reduces the maximum output
power that the supply can deliver, it typically will increase the efficiency, especially at
lower output power levels. To take the fullest advantage of the increase in efficiency that
can be obtained from ILIMIT–1 operation, the power transformer would need to be
redesigned slightly.
16 TNY277 and TNY279 Operation in EP-91
A TNY277 device used in the ILIMIT+1 mode (a 10 µF installed in place of C7) will work in
the EP-91 reference board, and deliver output power equal to that of a TNY278 device.
This flexibility allows a design engineer the option of using a lower cost part in
applications with less demanding thermal requirements.
A TNY279 device used in the ILIMIT–1 mode (a 1 µF installed in place of C7) will deliver
the same output power as a TNY278 in the standard ILIMIT configuration. This can
improve efficiency and lower the temperature rise of the device, which can give greater
thermal margin to a design that must operate in high ambient temperature environments.
Page 33 of 36
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EP-91 12 V, 1 A, Universal Input Supply
7-Feb-2006
17 OVP Operation Verification
While the EP-91 is in normal operation, monitor the output with a storage oscilloscope.
To cause an overvoltage condition to occur, short circuit the optocoupler LED (as shown
below) to open the feedback control loop. The oscilloscope will capture the output
voltage rising until the increasing voltage across VR2 causes it to conduct, and the
TNY278 device latches off. To reset the OVP latch, the AC input power must be
removed long enough to allow the input bulk capacitors to fully discharge.
Short these points to
test OVP functionality
Figure 33
– Point on PCB to Apply Short Circuit to Trigger OV Shutdown.
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Page 34 of 36
7-Feb-2006
EP-91 12 V, 1 A, Universal Input Supply
18 Revision History
Date
25-Jan-06
07-Feb-06
Page 35 of 36
Author
JAJ
JAJ
Revision
1.0
1.1
Description & changes
Formatted for Final Release
Formatted and corrected measurement
scales / div.
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EP-91 12 V, 1 A, Universal Input Supply
7-Feb-2006
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, Clampless, E-Shield, Filterfuse,
PI Expert and PI FACTS are trademarks of Power Integrations, Inc. Other trademarks are property of their respective companies.
©Copyright 2006 Power Integrations, Inc.
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: [email protected]
GERMANY
Rueckertstrasse 3
D-80336, Munich
Germany
Phone:
+49-89-5527-3910
Fax:
+49-89-5527-3920
e-mail: [email protected]
JAPAN
Keihin Tatemono 1st Bldg
2-12-20
Shin-Yokohama, Kohoku-ku,
Yokohama-shi, Kanagawa ken,
Japan 222-0033
Phone:
+81-45-471-1021
Fax:
+81-45-471-3717
e-mail:
[email protected]
TAIWAN
5F, No. 318, Nei Hu Rd., Sec. 1
Nei Hu Dist.
Taipei, Taiwan 114, R.O.C.
Phone:
+886-2-2659-4570
Fax:
+886-2-2659-4550
e-mail:
[email protected]
CHINA (SHANGHAI)
Rm 807-808A,
Pacheer Commercial Centre,
555 Nanjing Rd. West
Shanghai, P.R.C. 200041
Phone:
+86-21-6215-5548
Fax:
+86-21-6215-2468
e-mail: [email protected]
INDIA
261/A, Ground Floor
7th Main, 17th Cross,
Sadashivanagar
Bangalore, India 560080
Phone:
+91-80-5113-8020
Fax:
+91-80-5113-8023
e-mail: [email protected]
KOREA
RM 602, 6FL
Korea City Air Terminal B/D,
159-6
Samsung-Dong, Kangnam-Gu,
Seoul, 135-728, Korea
Phone:
+82-2-2016-6610
Fax:
+82-2-2016-6630
e-mail:
[email protected]
EUROPE HQ
1st Floor, St. James’s House
East Street, Farnham
Surrey, GU9 7TJ
United Kingdom
Phone:
+44 (0) 1252-730-140
Fax:
+44 (0) 1252-727-689
e-mail: [email protected]
CHINA (SHENZHEN)
Room 2206-2207, Block A,
Elec. Sci. Tech. Bldg.
2070 Shennan Zhong Rd.
Shenzhen, Guangdong,
China, 518031
Phone:
+86-755-8379-3243
Fax:
+86-755-8379-5828
e-mail: [email protected]
ITALY
Via Vittorio Veneto 12
20091 Bresso MI
Italy
Phone: +39-028-928-6000
Fax: +39-028-928-6009
e-mail: [email protected]
SINGAPORE
51 Newton Road,
#15-08/10 Goldhill Plaza,
Singapore, 308900
Phone:
+65-6358-2160
Fax:
+65-6358-2015
e-mail:
[email protected]
APPLICATIONS HOTLINE
World Wide +1-408-414-9660
Power Integrations
Tel: +1 408 414 9200 Fax: +1 408 414 9201
www.powerint.com
APPLICATIONS FAX
World Wide +1-408-414-9760
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