dm00102177

AN4419
Application note
VIPER37HE: 15 W wide range single output evaluation board
By Fabio Cacciotto
Introduction
This application note describes a 15 W wide range evaluation board, based on Viper37HE,
which is designed as an example of an isolated auxiliary power supply.
The board and the transformer were designed and optimized in order to have a very
compact size evaluation board.
February 2014
DocID025645 Rev 1
1/18
www.st.com
Contents
AN4419
Contents
1
Test board: design and evaluation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1
Output voltage characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
1.2
Efficiency and light load measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
1.3
No-load and light load consumptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
1.4
Typical board waveforms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
2
Conducted noise measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
3
Thermal measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
4
Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
5
Evaluation tools and documentation . . . . . . . . . . . . . . . . . . . . . . . . . . 16
6
Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
2/18
DocID025645 Rev 1
AN4419
Test board: design and evaluation
1
Test board: design and evaluation
Table 1 summarizes the electrical specification of the power supply, Table 2 provides the
BOM and Table 4 lists transformer's spec. The electrical schematic is shown in Figure 2 and
the PCB layout in Figure 3 and Figure 4.
Table 1. VIPer37H evaluation board electrical specification
Parameter
Min.
Typ.
Max.
Unit
AC Main Input voltage
100
265
VAC
Mains frequency (fL)
50
60
Hz
12.3
V
1.25
A
50
mV
Output Voltage
11.7
12 V
Output Current
Output ripple voltage
Rated output power
15
W
50
Input power in standby @ 230VAC
Active mode efficiency
mW
78
%
Ambient operating temperature
60
°C
Figure 1. Electrical schematic
L1
T1
+
L2
12V-1.25A
3.3uH
1mH
BR
RMB6S
D6
STPS5H100UF
C2
15uF
C3
15uF
C4
1nF
R1
220k
C9
470uF
C10
100uF
C11
1uF
-
D1
STTH1L06A
3
2
D4
BAT41ZFILM
D3
GND
R7
1k
BAT41ZFILM
R2
4.7
R3
133K
4
1
CM
2X20mH
R12
2.2M
C1
D2
BAT41ZFILM
OPTO
SFH610A-2
R8
12k
IC1
220nF - X2
VIPER37HE
NTC
16
C5
220pF
RV
VDD
DRAIN
R10
130k
BR
320V
R5
220
F1
C6
33uF
R9
82k
CONTROL
CONT
2A
FB
GND
C12
10nF
D5
18V
AC IN
AC IN
R4
30k
C8
33nF
IC2
TS432
C7
2.2nF
R6
47k
OPTO
SFH610A-2
R11
15k
C13
2.2nF
DocID025645 Rev 1
AM18323v1
3/18
18
Test board: design and evaluation
AN4419
Figure 2. Evaluation board (30 x 72 mm) max
AM18336v1
Table 2. VIPer37H evaluation board: bill of material
Reference
Part
Description
Note
R1
220 kΩ
0.33 W – 200 V
R2
4.7 Ω
1% tolerance
R3
133 kΩ
1% tolerance
R4
30 kΩ
1% tolerance
R5
220 Ω
0.25 W
R6
47 kΩ
1% tolerance
R7
1 kΩ
R8
12 kΩ
R9
82 kΩ
1% tolerance
R10
130 kΩ
1% tolerance
R11
15 kΩ
1% tolerance
R12
2.2 MΩ
1% tolerance
C1
BFC233920224
220 nF - 275 V x 2
Vishay
C2, C3
450BXF15M10X20
15 μF - 450 V electrolytic
Rubycon
C4
C3216C0G2J102JT
1 nF - 630 V MLCC
TDK
C5
GRM188R71H221KA01D
220 pF - 16 V MLCC
Murata
C6
35YXM33MEFC5X11
33 μF - 35 V electrolytic
Rubycon
C7
GRM1885C1H222FA01D
2.2 nF - 50 V MLCC
Murata
C8
GRM188R71H333KA61D
33 nF -16 V MLCC
Murata
C9
25ZLJ470M10X12.5
470 μF - 25 V electrolytic
Rubycon
4/18
DocID025645 Rev 1
AN4419
Test board: design and evaluation
Table 2. VIPer37H evaluation board: bill of material (continued)
Reference
Part
Description
Note
C10
25YXJ100M5X11
100 μF - 25 V electrolytic
Rubycon
C11
GRM188C81E105KAADD
1 μF - 25 V MLCC
Murata
C12
GRM188R71H103KA01D
10 nF - 50 V MLCC
Murata
C13
DE2E3KY222MA2BM01
2.2 nF - 250 V X1/Y1 CAP
Murata
D1
STTH1L06A
Ultra-fast diode 600 V - 1 A
STMicroelectronics
D2, D3, D4
BAT41ZFILM
Signal Schottky diode
STMicroelectronics
D5
MMSZ5248B-V-GS08
18 V Zener diode
Vishay
D6
STPS5H100B
Power Schottky 100 V - 5 A
STMicroelectronics
L1
B82144A2105J
1 mH Axial inductor
Epcos
L2
SD43-332ML
3.3 μH Power inductor
Coilcraft
CM
744821120
20 mH CM choke
Wurth Elektronik
IC1
VIPer37LE
Offline HV converter
STMicroelectronics
IC2
TS432ILT
1.24 V Shunt voltage reference
STMicroelectronics
OPTO
SFH610A-2
Optocoupler
Vishay
TF
YJ-310V600210
Flyback transformer
Yujing Technology
BR
RMB6S
Bridge 600 V - 1 A
Taiwan Semiconductor
NTC
B57236S160M
NTC Inrush current limiter
Epcos
Fs
0461002.ER
2 A fuse
Littlefuse
Note:
If not otherwise specified, all resistors are ± 5%, 0.1 .
Table 3. Transformer characteristic
Reference
Description
Manifacturer
Yujing Technology CO. LTD.
Part number
YJ-310V600210
Core
EEE - 13 V
Ferrite
3C94 Ferroxcube
Primary Inductance
0.85 mH ±10%.
Leakage inductance
40 µH max
Primary turns (N1+N3)
75
Secondary turns (N2)
12
Auxiliary turns (N4)
14
DocID025645 Rev 1
5/18
18
Test board: design and evaluation
AN4419
Figure 3. Electrical scheme
AM18338v1
Figure 4. Drawing transformer (mm.)
AM18337v1
6/18
DocID025645 Rev 1
AN4419
1.1
Test board: design and evaluation
Output voltage characteristics
The output voltage of the board is measured in different line and load conditions. Figure 5
shows the results: the output voltage variation range is a few tens mV for all the tested
conditions.
All output voltages have been measured on the output connector of the board.
Figure 5. Line and load regulation
AM18324v1
12.3
Output voltage [V]
12.2
12.1
12.0
115 Vac
230 Vac
11.9
11.8
0.00
0.25
0.50
0.75
1.00
1.25
1.50
Output current [mA]
1.2
Efficiency and light load measurements
Any external power supply (EPS) must be capable to meet the international regulation
agency limits. The European code of conduct (EC CoC) and US department of energy
(DoEUS EISA 2007) limits are taken as reference. EPS limits are fixed up to 77.76%, when
the average efficiency is measured. The average efficiency measures the average value at
25%, 50%, 75% and 100% of the rated output power, at both 115 VAC and 230 VAC.
Figure 6 shows the results.
DocID025645 Rev 1
7/18
18
Test board: design and evaluation
AN4419
Figure 6. Efficiency vs. output power
AM18325v1
88
86
84
Efficiency [%]
82
80
EC Code of Conduct
78
76
115 Vac
230 Vac
average @ 115 Vac
average @ 230 Vac
74
72
70
0
2
4
6
8
10
12
14
16
Output power [W]
1.3
No-load and light load consumptions
No-load consumptions and light load consumption are two important parameters that must
be considered when selecting the IC controller and very often they are the key parameters
of choice.
The presented board was optimized in order to provide an extremely low consumption at
zero load but also in order to meet EµP Lot 6 energy saving regulation, which requires that
the efficiency of the converter must be higher than 50% when the output is loaded with
250 mW.
In Figure 7 and Figure 8 the consumption in the said condition are shown.
Figure 7. No load consumption vs. input voltage
AM18326v1
65
60
55
50
Input power [mW]
45
40
35
30
25
20
15
10
50
100
150
200
Input voltage [Vac]
8/18
DocID025645 Rev 1
250
300
AN4419
Test board: design and evaluation
Figure 8. Light load consumptions at 250 mW O/P
AM18327v1
500
Input power [mW]
450
400
250 mW
350
300
250
200
50
100
150
200
250
300
Input voltage [Vac]
1.4
Typical board waveforms
In this section, typical waveforms are reported.
Drain voltage and current waveforms were reported at nominal input voltages and full load
in Figure 9 and Figure 10.
The startup phase is shown in Figure 11 and Figure 12: the IC starts with very clean
waveforms and no overshoot/undershoot appear on the output.
Finally also the output voltage when the converter is submitted to dynamic load variations is
measured, in order to be sure that good stability is ensured and no overvoltage on
undervoltage occurs
The board was submitted to dynamic load variations from 0% to 100% load (Figure 13 and
Figure 14): no abnormal oscillations were noticed on the output and the over/under shoot
were well within acceptable values.
DocID025645 Rev 1
9/18
18
Test board: design and evaluation
AN4419
Figure 9. Drain current and voltage at full load 115 VAC
AM18328v1
I DS
VDS
Ch1 (Max): 340 V
Ch2 (Max): 596.mA
M: 4.0 µs/div
Figure 10. Drain current and voltage at full load 230 VAC
AM18329v1
I DS
VDS
Ch1 (Max): 517 V
Ch2 (Max): 612 mA
10/18
DocID025645 Rev 1
M: 4.0 µs/div
AN4419
Test board: design and evaluation
Figure 11. Startup at full load and 115 VAC
AM18330v1
VOUT
VDD
VD S
Ch3 (Max): 12.04 V
M: 40 ms/div
Figure 12. Startup at full load and 230 VAC
AM18331v1
VOUT
VDD
VD S
Ch3 (Max): 12.06 V
DocID025645 Rev 1
M: 40 ms/div
11/18
18
Test board: design and evaluation
AN4419
Figure 13. Step load at 115 VAC
AM18332v1
VOUT
IOUT
Ch1 (Max): 0 A
Ch1 (Min): 1.26 A
Ch2 (Max): 12.07 V
Ch2 (Min): 11.73 V
M: 20 .0 ms/div
Figure 14. Step load at 230 VAC
AM18333v1
VOUT
IOUT
Ch1 (Max): 0 A
Ch1 (Min): 1.26 A
12/18
Ch2 (Max): 12. 06 V
Ch2 (Min): 11.7 4 V
DocID025645 Rev 1
M: 20 .0 ms/div
AN4419
2
Conducted noise measurements
Conducted noise measurements
A pre-compliance test for EN55022 (Class B) European normative was performed using
peak measurements detector of the conducted noise emissions at full load and nominal
mains voltages. Figure 15 and Figure 16 show the results. As seen in the diagrams, in all
test conditions there is a good margin for the measurements with respect to the AV and QP
limits, also using the peak detector with max-hold function.
Figure 15. CE average measurement at 115 VAC and full load
AM18334v1
Figure 16. CE average measurement at 230 VAC and full load: Peak measurement
AM18335v1
DocID025645 Rev 1
13/18
18
Thermal measurements
3
AN4419
Thermal measurements
A thermal analysis of the board was performed using an IR camera.
The board was submitted to full load at nominal input voltage and the thermal map was
taken 30 min. after the power on at ambient temperature (25 °C).
Figure 17, Figure 18, Figure 19 and Figure 20 show the results.
Figure 17. Thermal map at 115 VAC and full load Figure 18. Thermal map at 115 VAC and full load
top side
bottom side
Figure 19. Thermal map at 230 VAC and full load Figure 20. Thermal map at 230 VAC and full load
top side
bottom side
14/18
DocID025645 Rev 1
AN4419
4
Conclusions
Conclusions
A 15 W wide range single output flyback converter using the new VIPer37HE has been
introduced and the results are presented.
The transformer arrangement and the very compact sizes make the PSU suitable as
external adapter or as an auxiliary power supply in all the applications where performances
and dimensions are the main constrains.
The efficiency performances were compared with requirements of the most important
international regulation agencies for external AC-DC adapters, resulting in a wide margin
respect the minimum required.
DocID025645 Rev 1
15/18
18
Evaluation tools and documentation
5
AN4419
Evaluation tools and documentation
The VIPer37LE evaluation board order code is: STEVAL-ISA140V1.
Further information about this product are available in the VIPer37 datasheet at
www.st.com.
16/18
DocID025645 Rev 1
AN4419
6
Revision history
Revision history
Table 4. Document revision history
Date
Revision
24-Feb-2014
1
Changes
Initial release.
DocID025645 Rev 1
17/18
18
AN4419
Please Read Carefully:
Information in this document is provided solely in connection with ST products. STMicroelectronics NV and its subsidiaries (“ST”) reserve the
right to make changes, corrections, modifications or improvements, to this document, and the products and services described herein at any
time, without notice.
All ST products are sold pursuant to ST’s terms and conditions of sale.
Purchasers are solely responsible for the choice, selection and use of the ST products and services described herein, and ST assumes no
liability whatsoever relating to the choice, selection or use of the ST products and services described herein.
No license, express or implied, by estoppel or otherwise, to any intellectual property rights is granted under this document. If any part of this
document refers to any third party products or services it shall not be deemed a license grant by ST for the use of such third party products
or services, or any intellectual property contained therein or considered as a warranty covering the use in any manner whatsoever of such
third party products or services or any intellectual property contained therein.
UNLESS OTHERWISE SET FORTH IN ST’S TERMS AND CONDITIONS OF SALE ST DISCLAIMS ANY EXPRESS OR IMPLIED
WARRANTY WITH RESPECT TO THE USE AND/OR SALE OF ST PRODUCTS INCLUDING WITHOUT LIMITATION IMPLIED
WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE (AND THEIR EQUIVALENTS UNDER THE LAWS
OF ANY JURISDICTION), OR INFRINGEMENT OF ANY PATENT, COPYRIGHT OR OTHER INTELLECTUAL PROPERTY RIGHT.
ST PRODUCTS ARE NOT DESIGNED OR AUTHORIZED FOR USE IN: (A) SAFETY CRITICAL APPLICATIONS SUCH AS LIFE
SUPPORTING, ACTIVE IMPLANTED DEVICES OR SYSTEMS WITH PRODUCT FUNCTIONAL SAFETY REQUIREMENTS; (B)
AERONAUTIC APPLICATIONS; (C) AUTOMOTIVE APPLICATIONS OR ENVIRONMENTS, AND/OR (D) AEROSPACE APPLICATIONS
OR ENVIRONMENTS. WHERE ST PRODUCTS ARE NOT DESIGNED FOR SUCH USE, THE PURCHASER SHALL USE PRODUCTS AT
PURCHASER’S SOLE RISK, EVEN IF ST HAS BEEN INFORMED IN WRITING OF SUCH USAGE, UNLESS A PRODUCT IS
EXPRESSLY DESIGNATED BY ST AS BEING INTENDED FOR “AUTOMOTIVE, AUTOMOTIVE SAFETY OR MEDICAL” INDUSTRY
DOMAINS ACCORDING TO ST PRODUCT DESIGN SPECIFICATIONS. PRODUCTS FORMALLY ESCC, QML OR JAN QUALIFIED ARE
DEEMED SUITABLE FOR USE IN AEROSPACE BY THE CORRESPONDING GOVERNMENTAL AGENCY.
Resale of ST products with provisions different from the statements and/or technical features set forth in this document shall immediately void
any warranty granted by ST for the ST product or service described herein and shall not create or extend in any manner whatsoever, any
liability of ST.
ST and the ST logo are trademarks or registered trademarks of ST in various countries.
Information in this document supersedes and replaces all information previously supplied.
The ST logo is a registered trademark of STMicroelectronics. All other names are the property of their respective owners.
© 2014 STMicroelectronics - All rights reserved
STMicroelectronics group of companies
Australia - Belgium - Brazil - Canada - China - Czech Republic - Finland - France - Germany - Hong Kong - India - Israel - Italy - Japan Malaysia - Malta - Morocco - Philippines - Singapore - Spain - Sweden - Switzerland - United Kingdom - United States of America
www.st.com
18/18
DocID025645 Rev 1
Similar pages