Demoboard for Charger and Adapter 10W

Version 2.0, August 2003
Application Note
AN-EVALSF2-ICE2A0565Z-2
CoolSET
10W 5.0V Evaluation Board with ICE2A0565Z
Author:
Rainer Kling
Published by Infineon Technologies AG
http://www.infineon.com/CoolSET/
Power Management & Supply
N e v e r
s t o p
t h i n k i n g
10W 5V Demoboard using ICE2A0565Z on Board
Table of Contents
TABLE OF CONTENTS.......................................................................................................................... 1
INTRODUCTION ..................................................................................................................................... 2
APPLICATION.......................................................................................................................................... 2
COOLSET........................................................................................................................................... 2
LIST OF FEATURES .............................................................................................................................. 3
POWER SUPPLY SPECIFICATION....................................................................................................... 3
SCHEMATIC ........................................................................................................................................... 4
PCB COMPONENT LEGEND................................................................................................................. 5
PCB LAYOUT ......................................................................................................................................... 5
DESCRIPTION ........................................................................................................................................ 6
Introduction....................................................................................................................................... 6
Line Input.......................................................................................................................................... 6
Startup .............................................................................................................................................. 6
Operation Mode................................................................................................................................ 6
Softstart ............................................................................................................................................ 6
Snubber Network.............................................................................................................................. 6
Limitation of primary current............................................................................................................. 6
Output Voltage ................................................................................................................................. 6
Regulation ........................................................................................................................................ 6
BILL OF MATERIAL ............................................................................................................................... 7
TRANSFORMER CONSTRUCTION DOCUMENTATION ..................................................................... 8
PERFORMANCE DATA ......................................................................................................................... 9
EFFICIENCY............................................................................................................................................ 9
NO-LOAD INPUT POWER (STANDBY)...................................................................................................... 10
REGULATION AND POWER LIMITING ....................................................................................................... 10
W AVEFORMS AND SCOPE PLOTS .......................................................................................................... 12
Startup @ Low and High AC Line Input Voltage and Nominal Load ............................................. 12
Drain Source Voltage and Current During Normal Operation........................................................ 12
Load Transient Response (Loadjump from 10% Load until 100% Load) ...................................... 13
AC Output Ripple during Nominal Load and Normal Operation .................................................... 13
INPUT CAPACITOR IMPROVEMENT – SLOPE COMPENSATION ................................................................... 14
Input Capacitor Improvement......................................................................................................... 14
Slope Compensation ...................................................................................................................... 14
REFERENCES ...................................................................................................................................... 16
www.Infineon.com/CoolSET
Page 1 of 16
EVALSF2-ICE2A0565Z
V2.00
10W 5V Demoboard using ICE2A0565Z on Board
Introduction
Application
This document is an engineering report that describes an universal input power supply designed in a
typical off line flyback converter topology that utilizes the ICE2A0565Z CoolSET. The application
operates in discontinuous current mode using the frequency reduction during standby condition. The
board has one output voltage with secondary regulation.
This board was designed to demonstrate the basic performance, the features and the power capability
of the smallest CoolSET device ICE2A0565Z of the second generation of CoolSET in a DIP7
package with extended creepage distance for higher electrical strength.
CoolSET
CoolSET is a current mode PWM control IC and the power MOSFET CoolMOS within one
package designed for low cost switch mode power supplies (SMPS). CoolSET combines the
superior technology of CoolMOS and the optimized technology of the control IC with enhanced
protection features and improved standby power concept. The integrated propagation delay
compensation (patented by Infineon Technologies) prevents a current overshoot, the result is a
reduced electrical stress on the MOSFET, the transformer and the output diode. The 650V / 800V high
avalanche rugged CoolMOS eliminates or reduces the need for a heat sink and permits a SMPS
design with a simply RCD snubber and a low cost standard transformer design. The lowest area
specific Rdson leads to a high efficiency and an operation at high ambient temperature. CoolSET
permits always a safety operation during any error cases due to the integrated protection features.
Figure 1– EVALSF2-ICE2A0565Z
This document contains the list of features, the power supply specification, schematic, bill of material
and the transformer construction documentation. Typical operating characteristics are presented at the
rear of the report and consist of performance curves and scope waveforms.
Note:
Design calculations for the components and the transformer were performed in accordance with the
application note “AN–SMPS–ICE2AXXX for OFF – Line Switch Mode Power Supplies” and
FlyCal, a EXCEL based design software according to the application note AN-SMPS-ICE2AXXX. The
application note and FlyCal are available on the Internet: www.Infineon.com/CoolSET
www.Infineon.com/CoolSET
Page 2 of 16
EVALSF2-ICE2A0565Z
V2.00
10W 5V Demoboard using ICE2A0565Z on Board
List of Features
Feature
CoolSET Device ICE2A0565Z
External Sense
Adjustable Soft start
Modulated Gate drive
Over Load Protection with auto restart
Over Current Protection with auto restart
Over Temperature Shut Down with auto restart
Open Loop Protection with auto restart
Under Voltage Lock Out with auto restart
1
Drain Source Voltage 650V
Frequency Reduction
Internal Leading Edge Blanking
100 kHz working frequency
DIP7 Package with extended Creepage Distance
Standby Power according to European Commission
Table 1 – List of Features
Power Supply Specification
Description
Input Voltage
Line Regulation (85...270V)
Input Frequency
2
No Load Input Power (90VAC)
2
No Load Input Power (230VAC)
Output Voltage
AC Output Voltage Ripple
Output Current
Output Power Nominal
Peak Power
Total Regulation
Efficiency (90VAC)
Efficiency (270VAC)
Symbol
Min
Input Section
VACIN
85
f
47
Typ
Max
Units
115/230
<1
50/60
0.18
0.41
270
VAC
%
Hz
W
W
5.0
<50
2.0
10
16
±2
78
79
5.1
Output Section
VOUT
4.90
VRipple
IOUT
1.90
POUT
POUTmax
η
η
64
2.1
VDC
mVP-P
ADC
W
W
%
%
%
Environmental
Conducted EMI
Ambient Temperature
TA
0
Thermal Consideration
Transformer
CoolSET
Output Diode
Output Capacitors
50
40
60
70
20
75
EN55022B
°C
°C
°C
°C
°C
Table 2 – Power Supply Specification
1
2
VDSBR at Tj = 110°C
Frequency Reduction Mode (fStandby = 21 kHz) and POUT = 0W
www.Infineon.com/CoolSET
Page 3 of 16
EVALSF2-ICE2A0565Z
V2.00
10W 5V Demoboard using ICE2A0565Z on Board
Schematic
Figure 2 10W 5.0V ICE2A0565Z Power Supply Schematic
www.Infineon.com/CoolSET
Page 4 of 16
EVALSF2-ICE2A0565Z
V2.00
10W 5V Demoboard using ICE2A0565Z on Board
PCB Component Legend
W1
W2
Figure 3 Component Legend
PCB Layout
Figure 4 Board Layout - Component Side
www.Infineon.com/CoolSET
Page 5 of 16
EVALSF2-ICE2A0565Z
V2.00
10W 5V Demoboard using ICE2A0565Z on Board
Description
Introduction
The EVALSF2-ICE2A0565Z demoboard is a low cost off line flyback switch mode power supply
(SMPS) using the ICE2A0565Z system IC from the CoolSET-F2 family. The circuit, shown in Figure
2, details a 5.0V, 10W power supply that operates from an AC line input voltage range of 85 to
265VAC, suitable for applications requiring either an open frame supply or an enclosed adapter.
Line Input
The AC line input side comprises of an input fuse F1 as line input over current protection as well as
choke L5 and the X2 capacitor C8 as radio interference suppressors. After the bridge rectifier BR1
and input capacitor C3, a voltage from 120 to 380 VDC is present. Due to the extended duty cycle DMAX
3
of the ICE-F2-family there is the possibility to replace the 47µF input capacitor with a 22µF (2.2µF/W) .
Startup
From this voltage, the chip starting the current supply is derived using resistors R6 and R7. Because
of the very low start up current of typically 27µA, a high-value resistor can be used.
Operation Mode
During operation, the VCC pin is supplied via a separate transformer winding with associated
rectification D2 and buffering C4, C13. Resistor R8 is used for current limiting during the charging of
C4. In order not to exceed the maximum voltage at VCC pin an external zener diode D4 limits this
voltage. During light or no load condition, the switching frequency is automatically and continuously
4
reduced down to 21kHz in order to reduce the switching losses.
Softstart
The Soft-Start function is realized by an internal resistor and the adjustable external capacitor C14.
Snubber Network
The network R10, C12 and D3 clamp the DRAIN voltage spike caused by transformer leakage
5
inductance to a safe value below the drain source break down voltage VDSBR = 650V maximum.
Limitation of primary current
The CoolMOS drain source current is sensed via external shunt resistors R17. An accurate value of
the shunt improves the peak power limitation shown in the curve peak power limitation in the rear of
this report.
Output Voltage
Power is coupled out on the secondary side via a fast-acting diode D1 with low forward voltage.
Capacitor C5 performs energy buffering, a following LC - filter C9 and inductor L3 considerably
reduces the output voltage ripple. Storage output capacitor C5 is designed to exhibit a very low ESR in
order to minimize the output voltage ripple caused by the triangular 100kHz current characteristic. The
output voltage is set with resistors R1 and R2.
Regulation
The output voltage is controlled using a type TL431 reference diode (IC2). This device incorporates
the voltage reference as well as the error amplifier and a driver stage. Compensation network C1, C2,
R1, R5 constitutes the external circuitry of the error amplifier of IC2. This circuitry allows the feedback
to be precisely matched to dynamically varying load conditions, thereby providing stable control. The
maximum current through the optocoupler diode and the voltage reference is set by using resistors
R3, R4. Optocoupler IC1 is used for floating transmission of the control signal to the “Feedback” input
via resistor R9 and capacitor C6 of the ICE2A0565Z control device. The optocoupler used meets DIN
VDE 884 requirements for a wider creepage distance.
3
4
5
Slope Compensation is needed due to Current Mode Control and Dnom > 50% see description in the rear of the report
Without audible noise
VDSBR = 650V @ Tj = 110°C
www.Infineon.com/CoolSET
Page 6 of 16
EVALSF2-ICE2A0565Z
V2.00
10W 5V Demoboard using ICE2A0565Z on Board
Bill of Material
ICE2A0565Z Evaluation Board 5.0V/ 10W
Pos.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
Part
Type
Number
BR1
B500 C1500
1
C1 [nF]
470
1
C2 [nF]
10
1
C3 [µF]
47
1
C4 [µF]
22
1
C5 [µF]
1000
1
C6 [nF]
2.2
1
C7 [nF]
2.2
1
C8 [µF]
0.1
1
C9 [µF]
470
1
C12 [nF]
1.0
1
C13 [nF]
100
1
C14 [nF]
100
1
D1
MUR540
1
D2
1N4148
1
D3
1N4937
1
D4
ZPD18
1
F1
Microfuse 3.15A
1
IC1
SFH617A-3X016
1
IC2
TL431CLP
1
IC3
ICE2A0565Z
1
L3 [µH]
1.0
1
L5 [µH]
2*27mH / 0.9A
1
R1 [kOhm]
3.3
1
R2 [kOhm]
3.3
1
R3 [kOhm]
0,082
1
R4 [kOhm]
1.2
1
R5 [kOhm]
2,7
1
R6 [kOhm]
360
1
R7 [kOhm]
360
1
R8 [Ohm]
4.3
1
R9 [Ohm]
22
1
R10 [kOhm]
100
1
R17 [Ohm]
1.1
1
TR1
E20/10/6
1
W1
Wire
1
W2
Wire
1
X1
Connector 2pol.
1
X2
Connector 2pol.
1
www.Infineon.com/CoolSET
Values
Page 7 of 16
Others
50V X7R
50V X7R
400V B43504-A9476-M
63V
25V Low ESR – B41886
50V X7R
250V Y1 Cap
275V X2 Cap
25V Low ESR – B41886
400V MKT
50V X7R
50V X7R
400V
18V
3.15A
6A 262LYF-0074M
0.9A
1%
0.50 Mm
EVALSF2-ICE2A0565Z
V2.00
10W 5V Demoboard using ICE2A0565Z on Board
Transformer Construction Documentation
Core Material: E20/10/6; N87
Frequency: 100 kHz
gap: 0.5mm
Al = 103nH
Lp = 503µH
Coil former: horizontal version
35 turns 2 x 0,2 mm Ø
Prim.
4 turns 3 x 0,5 mm Ø
Sec.
10 turns 3 x 0,2 mm Ø
Aux.
35 turns 2 x 0,2 mm Ø
Prim
Pin
1
Pin
Pi
2n8
Pin 10
Pin 5
Pin 4
Pin 2
Pin 3
center
leg
meens one layer Makrofol
Top view:
Pin 1
Pin 2
Pin 3
Pin 4
Pin 5
www.Infineon.com/CoolSET
Pin 10
Pin 9
Pin 8
Pin 7
Pin 6
Page 8 of 16
EVALSF2-ICE2A0565Z
V2.00
10W 5V Demoboard using ICE2A0565Z on Board
Performance Data
Efficiency
Efficiency versus AC Line Input Voltage
100
Efficiency [%]
90
80
70
60
50
50
100
150
200
250
300
AC Line Input Voltage [V]
Efficiency @ 10W Output Power
Figure 5 Efficiency vs. AC Line Input Voltage
Efficiency versus Output power
100
90
80
Efficiency [%]
70
60
50
40
30
20
10
0
0
1
2
3
4
5
6
7
8
9
10
11
12
Output Power[W]
Vacin = 85V
Vacin = 270V
Figure 6 Efficiency vs. Output Power @ Low and High Line 50Hz
www.Infineon.com/CoolSET
Page 9 of 16
EVALSF2-ICE2A0565Z
V2.00
10W 5V Demoboard using ICE2A0565Z on Board
No-Load Input Power (Standby)
Standby versus AC Line Input Voltage
0,7
TAMB = 25 °C
0,6
Input Power [W]
0,5
0,4
0,3
0,2
0,1
0
50
100
150
200
250
300
AC Line Input Voltage [V]
Standby Power
Figure 7 No Load Input Power (Standby) vs. AC Line Input Voltage @ Pout = 0W
Regulation and Power Limiting
Line Regulation: Vout versus AC Line Input Voltage @ nominal Load
6
Output Voltage [V]
5,75
5,5
5,25
5
4,75
4,5
4,25
4
50
100
150
200
250
300
AC Line Input Voltage [V]
Output Voltage
Figure 8 Line Regulation vs. AC Line Input Voltage
www.Infineon.com/CoolSET
Page 10 of 16
EVALSF2-ICE2A0565Z
V2.00
10W 5V Demoboard using ICE2A0565Z on Board
Load Regulation: Vout versus Load @ Vacin = 230V
6
5,75
Output Voltage [V]
5,5
5,25
5
4,75
4,5
4,25
4
0
1
2
3
4
5
6
7
8
9
10
11
12
Output Power [W]
Output Voltage
Figure 9 Load Regulation
Max. Overload Output Power (Peak Power) versus AC Line Input Voltage
Max. Overload Output Power [W]
18
17,5
17
16,5
16
15,5
15
14,5
14
50
100
150
200
250
300
AC Line Input Voltage [V]
Peak Power
Figure 10 Overload Output Power (Over Current Shut Off Threshold) vs. Line Input Voltage
www.Infineon.com/CoolSET
Page 11 of 16
EVALSF2-ICE2A0565Z
V2.00
10W 5V Demoboard using ICE2A0565Z on Board
Waveforms and Scope Plots
All waveforms and scope plots where recorded with a Tectronix TDS 745D
Startup @ Low and High AC Line Input Voltage and Nominal Load
Channel 1: Chip Supply Voltage (VCC)
Channel 2: Feedback Voltage (VFB)
Channel 3: Soft Start Voltage (VSS)
Channel 4: Output Voltage (VOUT)
Channel 1: Chip Supply Voltage (VCC)
Channel 2: Feedback Voltage (VFB)
Channel 3: Soft Start Voltage (VSS)
Channel 4: Output Voltage (VOUT)
Figure 11 Startup @ Vacin = 85V and nom. Load
Figure 12 Startup @ Vacin = 270V and nom.Load
Drain Source Voltage and Current During Normal Operation
Channel 1: Drain Current (ID)
Channel 4: Drain Source Voltage (VDS)
Dmax = 41% / VRsense = 800mV
Channel 1: Drain Current (ID)
Channel 4: Drain Source Voltage (VDS)
Dmax = 10% / VRsense = 800mV
Figure 13 Operation @ Vacin = 85V and nom. Load
Figure 14 Operation @ Vacin = 270V and nom.Load
www.Infineon.com/CoolSET
Page 12 of 16
EVALSF2-ICE2A0565Z
V2.00
10W 5V Demoboard using ICE2A0565Z on Board
Load Transient Response (Loadjump from 10% Load until 100% Load)
Channel 2: Feedback Voltage (VFB)
Channel 2: Feedback Voltage (VFB)
Figure 15 Loadjump @ Vacin = 85V and nom. Load
Figure 16 Loadjump @ Vacin = 270V and nom.Load
AC Output Ripple during Nominal Load and Normal Operation
AC Output
Voltage Ripple
High Frequency
Probe Coupling
Channel 1: AC Output Ripple (VACOUT)
VACOUTmax = ± 10mV
Details of AC output voltage ripple measurements. The probe
GND should be as short as possible to minimize the high
frequency probe coupling.
Figure 17 AC Output Voltage Ripple at nom. Load
Figure 18 AC Ripple Measurement Technique
www.Infineon.com/CoolSET
Page 13 of 16
EVALSF2-ICE2A0565Z
V2.00
10W 5V Demoboard using ICE2A0565Z on Board
Input Capacitor Improvement – Slope Compensation
Input Capacitor Improvement
In case you are using a smaller input capacitor (22µF instead of 47µF), the maximum duty cycle
increases. To make sure, that the board is not working in the continuous conduction mode, a different
transformer is necessary; otherwise, you have to assemble slope compensation on board.
Slope Compensation
Any kind of current mode controller needs to have slope compensation in case the application is
designed for the continuous conduction mode (CCM) and the maximum duty cycle exceeds the 50%
threshold. Below you see the impact on the system in case of an input capacitor reduction; with the
47µF bulk works the board in the discontinuous conduction mode (DCM) and a Dmax < 50%; with the
smaller 22µF bulk, the board is running in the continuous conduction mode (CCM) and Dmax > 50%.
Channel 1: Drain Current (ID)
Channel 4: Drain Source Voltage (VDS)
CIN = 47µF / Dmax = 43% / Pout = 12W / VACIN = 85V
Channel 1: Drain Current (ID)
Channel 4: Drain Source Voltage (VDS)
CIN = 22µF / Dmax = 72% / Pout = 12W / VACIN = 85V
Figure 19 DCM – Operation with Dmax < 50%
Figure 20 CCM – Operation with Dmax > 50%
To prevents an instability of the regulation loop, in case of CCM and Dmax > 50%, assemble just three
more components (2 ceramic capacitors C17 / C18 and one resistor R19) as shown in the circuit
diagram below.
Figure 21 Circuit Diagram Switch Mode Power Supply with Slope Compensation
More information regarding how to calculate the additional components, see in the application note
AN_SMPS_ICE2xXXX – available on the internet: www.infineon.com/CoolSET CoolSET F2.
www.Infineon.com/CoolSET
Page 14 of 16
EVALSF2-ICE2A0565Z
V2.00
10W 5V Demoboard using ICE2A0565Z on Board
Note:
The built-in transformer does not comply with EN60950 safety requirements
in respect of electrical isolation.
Change service
Issue status
1.0
1.2
2.0
Changes
First issue
Replace Device ICE2A165 with ICE2A0565Z
Update:
! Board
! BOM
! Transformer construction
Additional:
! Performance Data
! Slope Compensation
www.Infineon.com/CoolSET
Page 15 of 16
Date
02.05.2002
Aug. 2002
Aug. 2003
EVALSF2-ICE2A0565Z
V2.00
10W 5V Demoboard using ICE2A0565Z on Board
References
[1]
ICE2AXXX for OFF-Line Switch Mode Power Supplies
Application Note, Infineon Technologies
[2]
CoolSET -II
Off-line SMPS Current Mode Controller with High Voltage CoolMOS on Board
Datasheet, Infineon Technologies
Revision History
Application Note AN-EVALSF2-ICE2A0565Z-01
Actual Release: 2.0 Date: 2003-08-09
Previous Release: V1.0
Page of
actual
Rel.
--
Page of
Subjects changed since last release
prev. Rel.
--
See change service
www.Infineon.com/CoolSET
Page 16 of 16
EVALSF2-ICE2A0565Z
V2.00
Similar pages