This document discusses ST's offline power supply products. It begins with an introduction to ST, including its market segments and major product lines. It then covers offline power supply configurations and topologies like SMPS. The document outlines ST's new VIPer+ family, including its roadmap and product details. It also discusses new products, magnetic components, and design tools and recommendations. The overall summary provides context about ST's offline power supply portfolio and upcoming products.

1. ST Off-Line Power Supply
September 2011

2. Agenda
 ST brief Introduction
 Offline Common configurations
 SMPS Fundamentals
 SMPS Common Configurations
 New VIPer+ Family
 Roadmap
 Products
 Detailed description
 New products
 Magnetic Components
 Lunch
 Layout Recommendations
 Design Tools
2

3. ST brief introduction

4. Market Segments
30 % 38%
Automotive, Consumer,
Industrial and
Computer and
Wireless Multisegment Sector
Communication 31 % (“IMS”)
50/50 JV with Ericsson Infrastructure (“ACCI”)
Home Computer & Automotive Analog, Microcontrollers,
Entertainment Communication Products Power and Memories and
Major Product Lines & Displays Infrastructure Group MEMS Smartcards
Products
Wireless: Consumer: Computer: Automotive: Industrial:
Market Position* #2 #2 in Set Top Box #2 (HDD & Printers) #3 #1
Major Customers
* Source: iSuppli-2008 rankings, ST and ST-Ericsson
4

5. 2010 overall ranking
Revenue Revenue Revenue
2009 2010 2009 2010
Company Name Percent Percent Cumulative
Rank Rank Revenue($) Revenue($)
Change of Total Percent
1 1 Intel 32,187 40,394 25.5% 13.3% 13.3%
2 2 Samsung Electronics 17,496 27,834 59.1% 9.2% 22.4%
3 3 Toshiba 10,319 13,010 26.1% 4.3% 26.7%
4 4 Texas Instruments (1) 9,671* 12,994 34.4% 4.3% 31.0%
9 Renesas Electronics (2) 5,153
5 11,893* 130.8% 3.9% 34.9%
12 NEC Electronics 4,384
7 6 Hynix 6,246 10,380 66.2% 3.4% 38.3%
5 7 STMicroelectronics 8,510 10,346 21.6% 3.4% 41.7%
13 8 Micron Technology (3) 4,293* 8,876* 106.8% 2.9% 44.6%
6 9 Qualcomm 6,409 7,204 12.4% 2.4% 47.0%
14 10 Broadcom (4) 4,278 6,682* 56.2% 2.2% 49.2%
15 11 Elpida Memory 3,948 6,446 63.3% 2.1% 51.3%
8 12 AMD 5,207 6,345 21.9% 2.1% 53.4%
11 13 Infineon Technologies (5) 4,456* 6,319 41.8% 2.1% 55.5%
10 14 Sony (6) 4,468* 5,224 16.9% 1.7% 57.2%
18 15 Panasonic Corporation (7) 3,243* 4,946 52.5% 1.6% 58.8%
17 16 Freescale Semiconductor (8) 3,402* 4,357 28.1% 1.4% 60.3%
19 17 NXP (9) 3,240 4,028* 24.3% 1.3% 61.6%
23 18 Marvell Technology Group 2,572 3,633 41.3% 1.2% 62.8%
16 19 MediaTek 3,551 3,553 0.1% 1.2% 64.0%
20 20 nVidia 2,826 3,196 13.1% 1.1% 65.0%
Top 20 Companies 141,475 197,660 39.7% 65.0%
All Others 88,719 106,415 19.9% 35.0%
Total Semiconductor 230,194 304,075 32.1% 100.0%
Source: iSuppli, March 11th 2011
(x) * refers to M&A. Details provided on separate page.
5

6. 2010 ranking on ST SAM
2009 2010 Revenue Revenue Revenue
2009 2010 Revenue Revenue Percent Percent Cumulative
Rank Rank Company Name ($) ($) Change of Total Percent
1 1 Texas Instruments 9,671 12,994 34.4% 7.3% 7.3%
5 Renesas Electronics 5,146
2 11,469 122.9% 6.4% 13.8%
9 NEC Electronics 4,119
2 3 STMicroelectronics 8,093 9,778 20.8% 5.5% 19.3%
4 4 Intel 5,721 7,233 26.4% 4.1% 23.3%
3 5 Qualcomm 6,409 7,204 12.4% 4.1% 27.4%
8 6 Broadcom 4,278 6,682 56.2% 3.8% 31.1%
7 7 Infineon Technologies 4,456 6,319 41.8% 3.6% 34.7%
6 8 Toshiba 5,053 5,659 12.0% 3.2% 37.9%
11 9 Samsung Electronics 3,279 4,348 32.6% 2.4% 40.3%
12 10 NXP 3,235 4,024 24.4% 2.3% 42.6%
18 11 Panasonic Corporation 2,428 3,647 50.2% 2.1% 44.6%
10 12 MediaTek 3,551 3,553 0.1% 2.0% 46.6%
17 13 Marvell Technology Group 2,458 3,472 41.3% 2.0% 48.6%
15 14 Freescale Semiconductor 2,537 3,204 26.3% 1.8% 50.4%
13 15 nVidia 2,826 3,196 13.1% 1.8% 52.2%
16 16 Fujitsu Semiconductor Limited 2,537 3,059 20.6% 1.7% 53.9%
14 17 Sony 2,810 2,999 6.7% 1.7% 55.6%
20 18 Analog Devices 2,091 2,862 36.9% 1.6% 57.2%
19 19 ROHM Semiconductor 2,286 2,776 21.4% 1.6% 58.7%
23 20 Maxim Integrated Products 1,657 2,367 42.8% 1.3% 60.1%
Top 20 Companies 80,522 106,845 32.7% 60.1%
All Others 59,587 70,997 19.1% 39.9%
Total Semiconductor 140,109 177,842 26.9% 100.0%
SAM = TAM – DRAM – Flash – MPU - Opto Source: iSuppli, March 11th 2011
6

7. Manufacturing Locations
France Italy
(Crolles I & II, Rousset, Tours) (Agrate, Catania 6”& 8”)
China
Morocco (Shenzhen, Longgang)
Malta
Philippines
Malaysia
 2009 sales : US$ 8.51 billion Singapore
 2010 sales : US$ 10.346 billion
 Approx. 53,000 employees in the group Front-end fabs
 15 main production sites
Back-end fabs
 Advanced R&D centers in 10 countries

8. Innovation Investment
8

9. SMPS Fundamentals
9

10. Power Supply in Appliances
 Power ranges from 3W to 15W
 Non-isolated topologies are used where there
are no external electrical connection.
 Isolated topologies are used where there is a
possibility of user touching electrical points.
 Cost and simplicity are key drivers.
10

11. BUCK
11

12. Topology
S1
L1
V2
V1
+
+
IL
S2
12

13. Topology Applied
IIN
L
VS
IIND
Cout
IGND
13

14. Buck topology – ON time
L
IIND
On
Vsw
IM
ID
IL
14

15. Buck topology – Off time
L
IIND
Off
Vsw
IM
ID
IL
15

16. Current/Voltage Waveforms
S1 Vsw
L1 IS1
V2
V1
+
+
IL
IS2
S2
IL
16

17. Buck Example
17

18. Buck/Boost, Negative Output
VD
ISW
ID VOUT
VIN
IL RO
18

19. Negative Output Example
19

20. Continuous versus Discontinuous
 Continuous refers to continuous current in the
inductor, there is always positive current flowing
in the inductor.
Inductor current
Load Current
20

21. Continuous versus Discontinuous
 Discontinuous refers to the inductor current
going to zero during every clock cycle.
Inductor current
Load Current
21

22. Continuous versus Discontinuous
 Discontinuous mode has higher peak currents.
 Higher peak current lowers the efficiency.
 Higher peak current increases the EMI energy.
22

23. EMI considerations for the Buck
 EMI stands for ElectroMagnetic Interference and
is the result of noise generated by switching
devices.
 EMI has two components, radiated and
conducted.
 Radiated refers to the EMI that is “broadcast” into
the air by the module.
 Conducted refers to EMI on the power line
emitted by the module.
23

24. EMI Considerations for the Buck
 The buck has one switching point, the common
point of the two switches and the inductor.
 A simple RC snubber at this switching point is
the most common method of reducing EMI (both
conducted and radiated).
24

25. Reduction of EMI
IIN
Snubber
L
VS
IIND
Cout
IGND
25

26. Effect of Snubber on VS(t)
VS Ringing causes big EMI numbers
No snubber
Snubber lows frequency
and amplitude of ringing
With Snubber
50 100 150 T (ns)
26

27. FLYBACK
27

28. Topology
28

29. Topology Applied
IP IS
VIN
+ +
VP VS
VD
Note: NP = # of primary turns
NS = # of secondary turns
29

30. Transformer relationship
I1 I2
N1 V1 I2
N2 V2 I1 + +
V1 N1 N2 V1
2
N1 L1
N2
2 L2
Where NX = number of turns
LX = inductance of winding
30

31. Flyback topology – ON time
D1
+ 1
+
4
- +
IQ1
C2 Output DC
Input DC C1
- +
Q1
2
T1
3
-
- IQ1 ON OFF ON OFF
1 2
P1
T LP I Q1PK f SW VQ1
2
ID1

32. Flyback topology – OFF time
D1
+ 1
-
4
+ +
ID1 C2 Output DC
Input DC C1
+ -
Q1
2
T1
3
-
- IQ1 ON OFF ON OFF
VQ1
ID1

33. Charge and discharge of the core
I
V IN
L
P VOUT
L
S
t
33

34. Drain Switching Waveforms (DM)
34

35. Drain Switching Waveforms (CM)
35

36. Diode Switching Waveforms
36

37. Current/Voltage Waveforms (discontinuous)
VIN+VO*NP/NS
VIN
VD t
IPEAK
T
IP
IS
VIN
VP
-VO*NP/NS
VOUT
VS
VIN * NS/NP
37

38. Current/Voltage Waveforms (continuous)
VIN+VO*NP/NS
VIN
VD
IPEAK
IP
IS
VIN
VP
-VO*NP/NS
VOUT
VS
VIN * NS/NP
38

39. Quasi Resonant
VIN+VO*NP/NS VIN+VO*NP/NS
VIN
VIN VD t
VD t IPEAK
T
IP
IS
IPEAK VIN
T
IP VP
-VO*NP/NS
VOUT
VS
IS VIN * NS/NP
VIN
VP Key difference between a
discontinuous mode flyback and
QR flyback:
-VO*NP/NS 1) There is no dead time in QR
flyback.
2) QR flyback is a variable frequency
VOUT
scheme
VS
VIN * NS/NP
39

40. EMI considerations for a Flyback
 There are two commutation point in a flyback
 The primary side power switch.
 The secondary side diode switch
 EMI is created only if there is a high frequency
power dissipation event.
 For DM, the current is ~zero when the switch
turns on and the diode turns off.
 Most of the EMI is generated when the switch
turns off and the diode turns on (the current is
highest).
40

41. Reducing EMI
 High current tracks should be as short as possible
 Area enclosed by high current loops, as indicated in red
should be minimized
 It is recommended to place high current tracks close
each to other to compensate magnetic field and reduce
parasitic inductance
 Use snubber to decrease dV/dt. Snubbers should be
placed with minimum trace lengths
 Increase capacitance between primary and secondary
side of the transformer. Higher Leakage inductance
helps!!
 Connect the VIPer Drain to the deepest primary winding
41

42. Reducing EMI
VIN
+ +
VP VS
42

43. Auxiliary Supply
VOUT = < 40V
VIN = 160V
VAUX = 12V
43

44. Why Auxiliary Supply (1/2)
 The PWM control loop uses 10V/5mA for power.
 If the power supply is the input bus (rectified line
voltage) and VDD is ~10V then the PWM loop
will draw (160V-10V)*5mA=7.5W
 The secondary output can’t be used because
galvanic isolation is required
 Auxiliary supply allows low power consumption
and galvanic isolation.
 Cost is low.
44

45. Why Auxiliary Supply (1/2)
 Transformer action will also apply between the
secondary voltage and the auxiliary voltage.
 Fault tolerence when reference/opto fails: No
overvoltage seen at output.
 Short circuit behavior: with aux winding the max
output power is limited, no need to oversize
secondary side components.
45

46. Flyback Example
46

47. Buck Vs Flyback
Buck Flyback
 Lower cost  Higher cost
 Less components  Custom transformer
 Designed based on  Designed based on
output current output power
 Differential EMI critical  Common mode EMI
 Outputs must be critical
inaccessible to users  Users can touch output
 Single output commonly connectors or output
power stages
 Multiple outputs possible
47

48. Viper Family
48

49. Solutions for low-medium power SMPS
 The best energy saving approach
 Minimized stand-by power
 High efficiency
 The most reliable approach
 Avalanche rugged power section
 Integration of advanced protections
 Thermal shutdown sensor located on power section
 The most flexible approach
 Modular product: controller + power section
 Packages’ design and development
 The most profitable partner
 Continuous products’ innovation
 Technical support (competence centers, documentations, software)
 Excellence in quality and supply chain
49

50. Solutions for low-medium power SMPS
Primary Controllers Secondary Controllers
HV Converters
Sync. CC/CV
Rectification
REGULATE
Controller + MOSFET RECTIFY Efficiently Constant Voltage &
Current
AC VIPer Plus.
(optional)
DC
Replacement of the (Adapters,
diode Chargers,..)
DELIVER the
power to
Transformer’s
Primary
50

51. New VIPer Plus family
GND / SOURCE DRAIN + Technology
VDD DRAIN
+ Functionalities
VIPer+ + Protections
CONT / Lim
FB Function = VIPer+
51

52. + Technology
NEW
800V Power MOSFET
GND / SOURCE DRAIN
DRAIN
VDD Out
Out
VDD DRAIN On-Off On/Off
VIPER17 BR
Gate Gate
CONT CONTROL
CONT Sense Sense
FB Tmp1 Tmp1
Gnd
FB
Gnd1 Gnd
BR
SOURCE
NEW
BCD6 controller technology
52

53. + Functionalities
 Current mode converter with ADJUSTABLE IDLIM set point
 Frequency
 Fixed (60kHz or 115kHz) with JITTERING for EMI reduction
 Quasi Resonant operation with Frequency Fold-back function (x5)
 SOFT START UP: IDLIM increased cycle by cycle
 BURST MODE in low load condition with IDLIM fixed
 ADJUSTABLE IDLIM set point
 STAND BY consumption < 50 mW
53

54. + Protections
 Over voltage protection (OVP)
AUTO RESTART
 2nd over current protection (2nd OCP) MODE
after every fault
 Over load protection (OLP) condition
 Over temperature protection + hysteresis (OTP)
 Brown out protection
 Max Duty Cycle: 70%
54

55. SMPS topology and main applications
High features - Isolated Fly-back
VIPer17 VIPer27 VIPer37 Auxiliary PS, STB, DVD, Games console, LCD TV,
major appliances, Motor control, Power Meter,
Chargers, Adapters, PC Stand-by
Quasi Resonant - Isolated Fly-back
VIPer15 VIPer25 VIPer35 Auxiliary PS, STB, DVD, Games console, LCD TV,
major appliances, Motor control, Power Meter,
Chargers, Adapters, PC Stand-by
VIPer28 VIPer38 Peak Power Isolated Fly-back
DVD, Printer, ATX
Non Isolated converters
VIPer06 VIPer16 VIPer26 Home appliances, Small appliances, Lighting, Power
meter
DIP7 DIP7 DIP7 Basic features – Isolated Fly-back
SDIP10 Auxiliary PS, STB, DVD, Games console, LCD TV,
SSO10 SO16N SO16N
major appliances, Motor control, Power Meter,
Chargers, Adapters, PC Stand-by
1W……. …….15W(1) / 30W(2)
55

56. Main features
Basic features VIPer x7 VIPer x8 VIPer x5 VIPer x6
PWM operations Fixed Frequency (60 or 115kHz) with Fixed Frequency
Quasi Resonant (301 or 60 or 115kHz)
with settable IDLIM Jittering
with Jittering
800V Extra Power Simplified
Avalanche Rugged Brown out Brown out Non Isolated
Timer
loop
Burst Mode Over Voltage No auxiliary
Over
Temperature Over Load Delay Feedback
shut down disconnection
Soft start 2° OCP Auto restart
(fixed time)
Latched a
Auto restart Feedback
disconnection
(option only for VIPer06)
Latched OVP
(option for VIPer25LLD)
(1) 30kHz available only for VIPer06
56

57. HV Converter Portfolio
+ Roadmap
730V
30 18 5.5 3 1 620V
1 W (3)
VIPer22
VIPer12 VIPer50 VIPer100 VIPer53
VIPer20
30 24 7 4.5 3 1
800 V
Av.Rug.
30 mW(3) CTRL
VIPer17 VIPer27 VIPer37 VIPer x7
30 mW(3) CTRL
VIPer15 VIPer25 VIPer x5
30 mW(3)
CTRL
VIPer28 VIPer x8
30 mW(3)
CTRL
VIPer06 VIPer16 VIPer26 VIPer x6
4W(1) / 8W(2) 6W(1) / 12W(2) 12W(1) / 24W(2) 15W(1) / 30W(2) 20W(1) / 35W(2) 30W(1) / 50W(2)
SSO10 & DIP7 SO16N & DIP7 SO16N & DIP7 SDIP10
(1) Open frame, VIN = 85 - 264VAC , under development, SOP planned within 2011
(2) Open frame, VIN = 230VAC ±20%,
(3) Achievable consumption at no load with Vin 264VAC
57

58. Tools availability
Training Application Evaluation e-Design
Datasheet Spreadsheet Spice Model
(slides) Notes Boards Studio
VIPer17 Yes Yes Yes Yes Yes Yes Yes
VIPer27 Yes Yes Yes Yes Yes Yes Yes
Under Under Under Under
VIPer37 Preliminary Yes
development development development development
--
Under Under Under Under
VIPer06 Preliminary Yes
development development development development
--
VIPer16 Yes Yes Yes Yes Yes Yes Yes
VIPer26 Yes Yes Yes Yes Yes Yes --
Under Under
VIPer15 Yes Yes Yes Yes
development development
--
Under
VIPer25 Yes Yes Yes Yes
development
Yes --
Under --
VIPer28 Yes Yes Yes Yes Yes
development .
58

59. Evaluation Boards and ANs
VIPer 17 Order code Topology Input VAC Output Output Relevant AN Reference
Isolated
VIPER17LN STEVAL-ISA058V1 85-265 5W 5V / 1A AN2864 Stand-by PSU
Fly-back
Isolated
VIPER17HN STEVAL-ISA060V1 85-265 6W 12V / 0.5A AN2753 Stand-by PSU
Fly-back
Isolated Cell Phone
VIPER17HN EVLVIP17-5WCHG 90-265 5W 5V / 1A AN2840
Fly-back Battery Charger
Isolated
VIPER17HN STEVAL-ILL017V1 220 ±20% 3.5W 7V / 500mA AN2811 Led Driver
Fly-back
Isolated 5V / 500mA
VIPER17HN STEVAL-ISA062V1 85-265 5.5W AN2934 General Purpose
Fly-back 12V / 250mA
Isolated High Power
VIPER17HN EVLVIP27-7WLED 100-264 3.5W 10V / 350mA AN3212
Fly-back Factor Led Driver
VIPer 27 Order code Topology Input VAC Output Output Relevant AN Reference
Isolated
VIPER27LN EVLVIP27L-12WS 85-265 12W 5V / 2.4A AN2929 Auxiliary PSU
Fly-back
Isolated
VIPER27HN EVLVIP27H-12SB 85-265 11W 5V / 2.2A AN3011 Auxiliary PSU
Fly-back
Isolated High Power
VIPER27HN EVLVIP27-7WLED 100-264 7W 10V / 750mA AN3212
Fly-back Factor Led Driver
VIPer 37 Order code Topology Input VAC Output Output Relevant AN Reference
Isolated
VIPER37xx TBD 85-265 5V / 3A
Fly-back
Isolated
VIPER37xx TBD 85-265 12V / 1.3A
Fly-back
59

60. Evaluation Boards and ANs
VIPer 06 Order code Topology Input VAC Output Output Relevant AN Reference
12V / 300mA
VIPER06LS Non isolated
Under development 85-265 option TBD Home appliance
VIPER06HS Fly-back
( 5V /800mA)
Isolated
Under development 85-265 TBD TBD Home Appliance
Fly-back
VIPer 16 Order code Topology Input VAC Output Output Relevant AN Reference
Non isolated 12V / 5V (post
VIPER16LN STEVAL-ISA010V1 85-500 1.8W AN2872 Power Meter
buck converter reg.) / 150mA
Non Isolated AN3028
VIPER16LN EVLVIP16L-4WFN 85-265 4.5W 16V / 280mA Home appliance
Fly-back draft
Non Isolated - 5V / 400mA,
VIPER16LN STEVAL-ISA071V1 85-265 4W UM0920 Home appliance
Fly-back +7V / 160mA
Isolated Home appliance
VIPER16LN EVLVIP16L-5WFL 85-265 5W 12 / 350mA databrief
Fly-back Auxilairy PSU
Non Isolated 12V / 5V (post Small Home
VIPER16LD EVLVIP16LD-1W5 85-265 1.8W databrief
buck converter reg.) / 150mA Appliance
Non Isolated
VIPER16HN EVLVIP16H-4WFN 85-265 4.5W 16V / 280mA databrief Home appliance
Fly-back
VIPer 26 Order code Topology Input VAC Output Output Relevant AN Reference
Primary
VIPER26LD STEVAL-ISA081V1 Regulation 85-265 12.5W 12V, 3.3V / 1A UM0984 Home appliance
Fly-back
60

61. Evaluation Boards and ANs
VIPer 15 Order code Topology Input VAC Output Output Relevant AN Reference
Quasi-
Resonant AN3160
VIPER15LN STEVALVIP15L-6W 90-265 VAC 6W 12V, 500mA Auxiliary PSU
Isolated draft
Fly-back
Quasi-
Resonant
VIPER15LN EVLVIP15L-5WSB 90-265 VAC 5W 5V, 1A TBD Auxiliary PSU
Isolated
Fly-back
VIPer 25 Order code Topology Input VAC Output Output Relevant AN Reference
Quasi-
Auxiliary PSU
Resonant AN3286
VIPER25LN EVLVIP25L-10WSB 85-265 VAC 10W 5V, 2A STB
Isolated draft
Power Meter
Fly-back
VIPer 28 Order code Topology Input VAC Output Output Relevant AN Reference
Isolated Auxiliary PSU
VIPER28LN EVLVIPER28L-10W 85-265 VAC 12W 5V, 2.4A AN2950
Fly-back Printer
61

62. VIPer06 / 16 /26
Main Features Pin description
 800V, avalanche rugged power MOSFET
 PWM controller with drain current limit IDlim
 Adjustable current limit,IDlim
 Fixed frequency with Jittering
 high performance for stand-by & efficiency
 No need of auxiliary winding
 Automatic auto restart after faults
 Hysteretic thermal shutdown
 Direct feedback for non isolated SMPS
 Replacement of capacitive power supply
 GND
 Open loop protection
controller ground / power MOSFET Source
MAIN PARAMETERS
Power MOSFET CONTROLLER  VDD
(SuperMESH)
Main parameters (BCD6S)
controller supply voltage / ICHARGE output current
Break down voltage [V] 800  LIM
Current limit set-up, IDlim .
RDSon [Ohm] 30 /24 / 7
 FB
VDD [V] 9 ÷ 23 direct voltage feedback (in case of non isolated
SMPS)
FOSC [KHz] 30 or 60 or 115
 COMP
Max IDlim [mA] 420 / 740 Compensation network.
RTHJ-A [°C/W] (1) 80 Current loop feedback in case of isolated SMPS
 N.A.
POUT [W] @ 85-265 VAC 4 / 6 / 12
Not Available for user. (It can be connected to GND)
(1) Package SO16N, 100mm2 of Cu
 N.C.
(2) Open Frame
Not Connected
62

63. Schematics with VIPerx6
FLY-BACK / Fixed Freq.
VIPer06 / 16 / 26
NON ISOLATED
Simplified feedback loop
R3, R4
R1 D1 L1 T1 D3 VOUT
+ No Need auxiliary winding
R2 C6 + C4
C5
C1 + C2 + D2
GND
Low cost EMI filter
C1, C2, L1
- VIPER x6
DRAIN R3
Low cost clamp components
Controller
FB R2,D2,C6
GND COMP LIM VDD
R4 Short circuit protection
C3 C4 (automatic restart)
Default current limit
400mA / 700mA
63

64. Schematics with VIPerx6
FLY-BACK / FF
VIPer06 / 16 / 26
NON ISOLATED
Simplified feedback loop
R3, R4
R1 D1 L1 T1 D3 VOUT
+ No Need auxiliary winding
R2 C6 + C4
C5
C1 + C2 + D2
GND
Low cost EMI filter
C1, C2, L1
- VIPER x6
DRAIN R3
Low cost clamp components
Controller
FB R2,D2,C6
GND COMP LIM VDD
R4 Short circuit protection
C3 C4 (automatic restart)
RLIM
Current limit set-up - RLIM
<400mA or <700mA
64

65. Schematics with VIPerx6
FLY-BACK / FF
VIPer06 / 16 / 26
NON ISOLATED
Simplified feedback loop
R3, R4
R1 D1 L1 T1 D3 VOUT
+ No Need auxiliary winding
R2 C6 + C4
C5
C1 + C2 + D2
GND
Low cost EMI filter
C1, C2, L1
- VIPER x6
R5
DRAIN R3
D4
Low cost clamp components
Controller
FB R2,D2,C6
GND COMP LIM VDD
R4 Short circuit protection
C3 C4 (automatic restart)
Feedback disconnection
(automatic restart)
Default current limit
400mA / 700mA
VOUT ≥ 12 V
Stand-by optimization , 30 mW
D4, R5
65

66. Schematics with VIPerx6
FLY-BACK / FF
VIPer06 / 16 / 26
NON ISOLATED
Simplified feedback loop
R3, R4
R1 D1 L1
+ Need auxiliary winding
R2 C6 C4 + AUX
AC IN C1 + C2 + D2 T1 D3 VOUT
Low cost EMI filter
+ C1, C2, L1
- C5
GND Low cost clamp components
VIPER x6
R2,D2,C6
R5 R3
DRAIN
D4
Controller
FB Short circuit protection
(automatic restart)
GND COMP LIM VDD
R4
C3 C4 Feedback disconnection
(automatic restart)
Default current limit
400mA / 700mA
VOUT < 12 V
Stand-by optimization , 30 mW
D4, R5

67. Schematics with VIPerx6
FLY-BACK / FF
VIPer06 / 16 / 26
PRIMARY REGULATION
Simplified feedback loop
R3, R4
R1 D1 L1
+ Need auxiliary winding
R2 C6 C4 + AUX
AC IN C1 + C2 + D2 T1 D3 VOUT
Low cost EMI filter
+ C1, C2, L1
- C5
GND
R5 D4 Low cost clamp components
VIPER x6
R2,D2,C6
DRAIN
R3
Controller
FB Short circuit protection
(automatic restart)
GND COMP LIM VDD
R4
C3 C4 Feedback disconnection
(automatic restart)
Default current limit
400mA / 700mA
No need the optocoupler
Stand-by optimization , 30 mW
D4, R5

68. Schematics with VIPerx6
FLY-BACK / FF
VIPer06 / 16 / 26
ISOLATED
R1 D1 L1 Minimum components count
+
R2 C6
C1 C2
No Need auxiliary winding
AC IN + + D2 T1 D3 VOUT C4
+
- C5
Low cost EMI filter
GND
C1, C2, L1
R6 D4 C6
VIPER x6
DRAIN
Low cost clamp components
FB
R2,D2,C6
Controller
GND COMP LIM VDD Short circuit protection
C4
(automatic restart)
R5
R3
IC3 Default current limit
R4 C7 400mA / 700mA
IC2
C3 R4
68

69. Schematics with VIPerx6
FLY-BACK / FF
VIPer06 / 16 / 26
ISOLATED
R1 D1 L1 Minimum components count
+
R2 C6
C2
Need auxiliary winding
AC IN C1 + + D2 T1 D3 C4 + AUX
VOUT
+
- C5
Low cost EMI filter
GND
C1, C2, L1
R6 D4 C6
VIPER x6
DRAIN
Low cost clamp components
FB
R2,D2,C6
Controller
GND COMP LIM VDD Short circuit protection
C4
(automatic restart)
R5
R3
IC3
Feedback disconnection
R4 C7
(automatic restart)
IC2
Default current limit
C3 R4 400mA / 700mA
Stand-by optimization , 30 mW
AUX + D4, R5
69

70. VIPer17 / 27 / 37
Main Features Pin description
 800V, avalanche rugged power MOSFET *
 PWM controller with drain current limit, IDlim.
 Adjustable current limit, IDlim
 Fixed Frequency with Jittering
 High performance for stand-by & efficiency
 Integrated protections: OVP, OLP, high OCP
 Automatic auto restart after fault
 Hysteretic thermal shutdown
 Brown-out: minimum input voltage is settable
 GND
Power MOSFET CONTROLLER controller ground / power MOSFET Source
MAIN PARAMETERS
Main parameters
(SuperMESH) (BCD6S)  VDD
Break down voltage [V] 800 controller supply voltage / ICHARGE output current
 CONT
RDSon [Ohm] 24 / 7 / 4.5
OVP set-up, IDLIM set-up.
VDD [V] 9 ÷ 23  FB
current loop feedback
FOSC [KHz] 60 or 115
 BR *
Max IDlim [mA] 420 / 740 / 1050 brown out set-up
RTHJ-A [°C/W] (1) 50  N.A.
Not Available for user. (It can be connected to GND)
POUT [W] @ 85-265VAC 6 / 12 / 15
 N.C.
(1) Package SO16N and 100mm2 of Cu
Not Connected
(2) Open Frame
* BR pin has the position 10 for VIPER17LD/HD (SO16N package)
70

71. Schematics with VIPerx7
FLY-BACK / FF
VIPer17 / 27 / 37
ISOLATED
L1 30mW Stand-by
F
R2 C6
Minimum components count
AC IN C1 + C2 + D2 T1 D3
NTC VOUT
+
C5 Low cost EMI filter
GND C1,C2, L1
R6 D4 C6
VIPER x7
DRAIN
Low cost clamp components
R2,C6,D2
VDD
Controller
Default current limit
GND BR CONT FB
C4 400mA / 700mA / 1000mA
R5
R3
Short circuit protection
IC3
No need ext components
R4 C7
IC2 2nd Over Current protection
C3 R4 No need ext components
71

72. Schematics with VIPerx7
FLY-BACK / FF
VIPer17 / 27 / 37
ISOLATED
L1 30mW Stand-by
F
R2 C6
Minimum components count
AC IN C1 + C2 + D2 T1 D3
NTC VOUT
+
C5 Low cost EMI filter
GND C1,C2, L1
R6 D4 C6
VIPER x7
DRAIN
Low cost clamp components
R2,C6,D2
VDD
Controller
Current limit set-up - RLIM
GND BR CONT FB
C4 <400mA or <700mA or <1000mA
R5
R3
Short circuit protection
IC3
No need ext components
R4 C7
RLIM IC2 2nd Over Current protection
C3 R4 No need ext components
72

73. Schematics with VIPerx7
FLY-BACK / FF
VIPer17 / 27 / 37
ISOLATED
L1 30mW Stand-by
F
R2 C6
Minimum components count
AC IN C1 + C2 + D2 T1 D3
NTC VOUT
DOVP +
C5 Low cost EMI filter
GND C1,C2, L1
R6 D4 C6
VIPER x7
DRAIN
Low cost clamp components
ROVP
R2,C6,D2
VDD
Controller
Current limit set-up - RLIM
GND BR CONT FB
C4 <400mA or <700mA or <1000mA
R5
R3
Short circuit protection
IC3
No need ext components
R4 C7
RLIM IC2 2nd Over Current protection
C3 R4 No need ext components
Over Voltage Protection (VOUT)
RLIM , ROVP , DOVP
73

74. Schematics with VIPerx7
FLY-BACK / FF
VIPer17 / 27 / 37
ISOLATED
L1 30mW Stand-by
F
R2 C6
Minimum components count
AC IN C1 + C2 + D2 T1 D3
NTC VOUT
+
C5 Low cost EMI filter
GND C1,C2, L1
R6 D4 C6
VIPER x7
DRAIN
Low cost clamp components
R2,C6,D2
R7 VDD
Controller
Default current limit
GND BR CONT FB
C4 400mA / 700mA / 1000mA
R5
R3
Short circuit protection
IC3
No need ext components
R4 C7
R8
IC2 2nd Over Current protection
C6 C3 R4 No need ext components
Brown out set-up (VINDC)
R7,R8, C6
74

75. Schematics with VIPerx7
FLY-BACK / FF
VIPer17 / 27 / 37
ISOLATED
L1 30mW Stand-by
F
R2 C6
Minimum components count
AC IN C1 + C2 + D2 T1 D3
NTC VOUT
DOVP +
C5 Low cost EMI filter
GND C1,C2, L1
R6 D4 C6
VIPER x7
DRAIN
Low cost clamp components
ROVP
R2,C6,D2
R7 VDD
Controller
Current limit set-up - RLIM
GND BR CONT FB
C4 <400mA or <700mA or <1000mA
R5
R3
Short circuit protection
IC3
No need ext components
R4 C7
R8
RLIM
IC2 2nd Over Current protection
C6 C3 R4 No need ext components
Over Voltage Protection (VOUT)
RLIM , ROVP , DOVP
Brown out set-up (VINDC)
R7,R8, C6
75

76. VIPer28
Main Features Pin description
 800V, avalanche rugged power MOSFET
 PWM controller with drain current limit, IDlim.
 Adjustable current limit, IDlim
 Fixed Frequency with Jittering
 High performance for stand-by & efficiency
 Integrated protections: OVP, OLP, high OCP
 Automatic auto restart after fault
 Hysteretic thermal shutdown
 Extra Power Management
 GND
Power MOSFET CONTROLLER controller ground / power MOSFET Source
MAIN PARAMETERS
Main parameters
(SuperMESH) (BCD6S)  VDD
Break down voltage [V] 800 controller supply voltage / ICHARGE output current
 COMP
RDSon [Ohm] 7
OVP set-up, IDLIM set-up.
VDD [V] 9 ÷ 23  FB
current loop feedback
FOSC [KHz] 60 or 115
 EPT
Max IDlim [mA] 850 Extra Power Time set-up
RTHJ-A [°C/W] (1) 50  N.A.
Not Available for user. (It can be connected to GND)
POUT [W] @ 85-265VAC 12
 N.C.
(1) Package SO16N and 100mm2 of Cu
Not Connected
(2) Open Frame
76

77. Schematics with VIPerx8
FLY-BACK / FF
VIPer28
ISOLATED
L1 30mW Stand-by
F
R2 C6
Minimum components count
AC IN C1 + C2 + D2 T1 D3
NTC VOUT
+
C5 Low cost EMI filter
GND C1,C2, L1
R6 D4 C6
VIPER x8
DRAIN
Low cost clamp components
R2,C6,D2
VDD
Controller
Default current limit
GND EPT CONT FB
C4 400mA / 700mA / 1000mA
R5
R3
Short circuit protection
IC3
No need ext components
R4 C7
CEPT
IC2 2nd Over Current protection
C3 R4 No need ext components
Extra Power Timer
CEPT
77

78. VIPer15 / 25
Main Features Pin description
 800V, avalanche rugged power MOSFET
 Quasi-Resonant PWM controller with drain current
limit, IDlim.
 Adjustable current limit, IDlim
 Feed-Forward compensation
 High performance for stand-by & efficiency
 Integrated protections: OVP, OLP, high OCP
 Automatic auto restart after fault
 Hysteretic thermal shutdown
 Brown-out: minimum input voltage is settable
 GND
MAIN PARAMETERS
Power MOSFET CONTROLLER controller ground / power MOSFET Source
(SuperMESH) (BCD6S)
Main parameters  VDD
Break down voltage [V] 800 controller supply voltage / ICHARGE output current
 ZCD
RDSon [Ohm] 24 / 7
Zero Current Detection, Feed-Forward set-up, OVP
VDD [V] 9 ÷ 23 set-up, IDlim set point.
up to 150 (L type)  FB
FOSClim [KHz]
up to 225 (H type) Current loop feedback
Max IDlim [mA] 420 / 740  BR
RTHJ-A [°C/W] (1) 80
Brown out set-up
 N.A.
POUT [W] @ 85-26 VAC 6 / 12
Not Available for user. (It can be connected to GND)
(1) Package SO16N, 100mm2 of Cu
 N.C.
(2) Open Frame Not Connected
78

79. Schematics with VIPer x5
FLY-BACK / Quasi Res.
VIPer15 / 25
ISOLATED
L1 30mW Stand-by
F
R2 C6
Minimum components count
AC IN C1 + C2 +
D2 T1 D3
NTC VOUT
DOVP + Low cost EMI filter
C5
C1,C2, L1
GND
ROVP RFF
R6 D4 C6
Low cost clamp components
VIPER x5
R2,C6,D2
DRAIN
Controller
VDD Short circuit protection
No need ext components
GND BR ZCD FB
C4
2nd Over Current protection
R5
R3 No need ext components
IC3
C7
Zero current Detection (QR)
R4
RLIM , ROVP , DOVP, RFF
IC2
RLIM
C3 R4
Current limit set-up - RLIM
≤400mA or ≤700mA or ≤1000mA
Over Voltage Protection (VOUT)
RLIM , ROVP , DOVP
Feed-Forward
RFF
79

80. VIPER+ DETAILLE
80

81. 2 Dies
 Give flexibility to get the best technology for each
section
 Power MOSFET in SuperMESH Technology
 BCD6 controller technology
DRAIN
VDD
Out Out
BR/EPT On-Off On/Off
Gate Gate
CONT CONTROL
Sense Sense
FB Tmp1 Tmp1
Gnd Gnd1 Gnd
SOURCE
81

82. Power SECTION: 800V BVDSS
 Leakage inductance contributes to the power
dissipation
PL=1/2LL(Ipk)2fSWVclamp/(Vclamp-Vfl)
VDS
800V
Vclamp
High Vclamp reduces power loss
Vfl
Vindc
Off time On time t
82

83. VDD pin (IC supply)
GND / SOURCE DRAIN
VIPerx5*
VDD DRAIN
Viper16^
~
CONT+ / ZCD* / LIM^
VIPerx7+
FB VIPerx8~
~
BR*+ / EPT / COMP^
83

84. VDD pin: What you can do?
 To manage the power supply start-up
 HV start up current generator & soft start
 To keep alive the VIPer’s supply
 wide range voltage
 Viperx5, x7 & x8 (from 8.5V to 23V)
 Viperx6 (from 11.5V to 23V)
 To manage the power supply auto-restart
 with special low restart current from the HV start up current
generator
 To manage the Power supply turn-off
 when VDD<8.5V and VDRAIN<80V, Viperx5, x7 & x8
 when VDD<11.5V and VDRAIN<50V, Viperx6
84

85. VDD pin: IC turn-on & turn-off
GND / SOURCE DRAIN
HV start
VIN up
VDD DRAIN
IDS_
Aux
CH CONT
winding
FB BR
VDRAIN _START= 80V
VDD SOFT
START
Fsw = 0 KHz Fsw = 60 KHz Fsw = 0 KHz
VDD(max
)
VDD_ON
VDD_OF
F
VDD(restart)

86. VDD pin: IC auto-restart with fault
LOW controller consumptions LOW restart repetition rate
VIN
Fsw = 0 KHz Fsw = Fsw = 0 KHz Fsw = Fsw
60 KHz 60 KHz
VDD(max
)
IDD_FAULT = 300 uA
VDD_ON
IDS_CH =0.6 mA
IDD_OFF = 250 uA
VDD_OF
F
VDD(restart)

87. SOFT START UP
Soft start zone with Transient Steady state
growing IDLIM value zone
IDRAIN
8.5 ms
IDLIM
t
VFB
VFB_olp
VFB_lin
t
Advantages :
 Reduce the stress on the transformer
 Improving of the VIPer and system and reliability

88. FB pin (Viperx5, x7 & x8 )
GND / SOURCE DRAIN
VIPerx5*
VDD DRAIN
VIPerx7+
~
CONT+ / ZCD*
VIPerx8~
FB ~
BR*+ / EPT
88

89. FB pin: What you can do?
 To make the current mode control loop
 Error Amplifier Input
 To fix the loop stability
 Only in Viperx5, x7 & x8
 To manage the Over Load Protection
 Only in Viperx5, x7 & x8
 To enter the Burst Mode
 Only in Viperx5, x7 & x8
89

90. FB pin: IDRAIN versus VFB
IDRAIN
BURST MODE CURRENT MODE CONTROL OVER LOAD
OLP
IDLIM Shut down
drain current is
depending from
ID_BM the load
VFB
VFB_bm- VFB_bm_hys VFB_bm VFB_lin VFB_olp
90

91. FB pin: Current mode & loop stability
 Linear range: VFB from VFB_bm +VFB_bm_hys to VFB_lin
 CFB or CFB , RFB , CFB1 fixes the loop stability
The drain current is compared
with IFB in order to drive the PWM
The optocoupler current and the
IFB current are depending from Sense FET
the output load
+
FB
IFB PWM logic
R1 -
CFB
R2
RFB CFB1
CFB
91

92. FB pin: Over load protection
 VFB ≥ VFB_lin , V max load has been reached and the FB voltage is
controlled
 VFB = VFB_lin, 3uA current starts charging CFB
 VFB = VFB_olp, Power section is switched off for over load after the
OLP delay
OLP delay VFB _ olp VFB _ lin
VFB CFB
= 3 A
VFB_olp GND / SOURCE DRAIN
VIPERx5
VDD DRAIN
VFB_lin
CONT
VIPERx7
FB
VIPERx8 BR
VDS t 3 A
CFB
92

93. FB pin: OLP delay, why?
 IMMUNITY to over load NOISE during the normal operation
 IMMUNITY to false OLP and incorrect switch off before the
converter’s steady state conditions
93

94. FB pin: Burst Mode working mode
STAND-BY mode: less than 30
mW with
optimezed psu design
Converter frequency reduction by
VFB packets operation
VFB_bm- VFB_bm_hys
t
IDS
ID_BM
t
94

95. FB & COMP pin (Viperx6)
GND / SOURCE DRAIN
VDD DRAIN
Viper16^
LIM^
FB COMP^
95

96. FB & COMP (only for non isolated topology)
 Fly-back non isolated
 Buck
 Buck-Boost
 FB pin = EA input
 COMP pin = EA output
 FB pin takes the feedback directly from VOUT
 FB voltage is compared with the EA reference
 Loop is compensated by RCC to COMP pin
 PWM is performed comparing the EA output (COMP) with sense FET.
96

97. FB & COMP (only for isolated smps)
 Fly-back isolated with optocoupler
 FB pin = GND => EA disabled
 COMP pin takes the feedback from optocoupler
 Loop is compensated by RCC to COMP pin
 PWM is performed comparing the COMP signal with sense FET.
 PWM dynamic VCOMPL – VCOMPH
 V(COMP) < VCOMPL – 50mV => Burst Mode
 V(COMP) > VCOMPH => Current Limited to IDlim
97

98. FB & COM: Burst Mode working mode
 STAND-BY mode: less than 50 mW with optimezed psu
design
 Activated when COMP voltage decreases
 Low load
98

99. FB & COMP: Open loop failure protection
(with aux winding)
NON-ISOLATED
 If RUP is opened:
 V(OUT) increases and then V(VDD) increases (coupled by aux winding)
 I(DRAIN) = Idlim
 VDD pin has inside a clamp:
 If V(VDD) reaches the VDDclamp level and the injected current, IDD, exceeds the latch
threshold, IDDol, a fault signal is generated*
 If RDOWN is opened:
 V(OUT) is clamped to VREF_FB (3.3V typ)
99

100. FB & COMP: Open loop failure protection
(with aux winding)
ISOLATED
 If RUP is opened:
 V(OUT) increases and then V(VDD) increases (coupled by aux winding)
 I(DRAIN) = IDlim
 VDD pin has inside a clamp:
 If V(VDD) reaches the VDDclamp level and the injected current, IDD, exceeds the latch threshold, IDDol, a fault signal is
generated*
 If RDOWN is opened:
 V(OUT) is clamped to the voltage reference
100

101. CONT pin (Viperx7 & x8 )
GND / SOURCE DRAIN
VDD DRAIN
VIPerx7+
CONT+~
VIPerx8~
~
FB BR+ / EPT
101

102. CONT pin: What you can do?
 To choose the IDLIM level (RLIM)
 To fix the Over Voltage Protection (RLIM & ROVP, DOVP)
GND / SOURCE DRAIN
VDD DRAIN
DOVP ROVP VIPERx7
CONT
VIPERX8
Auxiliary FB BR / EPT
winding RLIM
102

103. CONT pin: IDLIM set point
Advantages :
 Transformer optimization and accurate OLP.
 Flexibility vs design changes
 Flexibility vs different Projects (stock optimization)
1.2
(Normalized to IDLIM whitout RLIM)
1.0
GND / SOURCE DRAIN
0.8
VDD VIPERx7 DRAIN
IDLIM
0.6
CONT VIPERX8
0.4
FB BR / EPT 0.2
RLIM
0.0
0 20 40 60 80 100
RLIM [K ]
103

104. CONT pin: Over Voltage Protection
R LIM 100K 1 kOVP VCONT = VOVP= 3V
ROVP RLIM
or k OVP VCONT
+ 3V
RLIM 50K
VDS
VOVP
K OVP
N AUX
VoutOVP VDSEC VDOVP
N SEC
GND / SOURCE DRAIN
VDD DRAIN
DOVP ROVP VIPerx7
CONT
VIPerx8
FB BR / EPT
Auxiliary
RLIM
winding
104

105. LIM pin (Viperx6)
GND / SOURCE DRAIN
VDD DRAIN
Viper16^
LIM^
FB COMP^
105

106. LIM pin: What you can do?
 To choose the IDLIM level (RLIM)
 RLIM>100 kOhm or pin float:
 IDlim default (typ, 400mA)
 RLIM< 80 kOhm:
 IDlim decreased continuously according to the current
sunk from the LIM pin 1.2
(Normalized to IDLIM whitout RLIM)
1.0
GND / SOURCE DRAIN
0.8
VDD DRAIN
IDLIM
0.6
LIM VIPERx6 0.4
FB 0.2
RLIM 0.0
0 20 40 60 80 100
RLIM [K ]
106

107. ZCD pin (Viperx5)
GND / SOURCE DRAIN
VDD DRAIN
VIPerx5*
ZCD*
FB BR*+
107

108. ZCD pin: What you can do?
 Transformer demagnetization Sensing (Zero Voltage Detection)
 To choose the IDLIM level (RLIM)
 To fix the Over Voltage Protection (RLIM & ROVP, DOVP)
 To have dynamic IDLIM Adjustment for almost constant maximum
power versus converter input voltage (Voltage Feed Forward
function)
GND / SOURCE DRAIN
VDD DRAIN
DOVP ROVP
ZCD VIPERx5
FB BR
RFF
Auxiliary RLIM
winding
108

109. ZCD pin: IDLIM set point
Advantages :
 Transformer optimization and accurate OLP.
 Flexibility vs design changes
 Flexibility vs different Projects (stock optimization)
1.2
(Normalized to IDLIM whitout RLIM)
1.0
GND / SOURCE DRAIN
0.8
VDD DRAIN
IDLIM
0.6
ZCD VIPERx5
0.4
FB BR 0.2
RLIM
0.0
0 20 40 60 80 100
RLIM [K ]
109

110. ZCD pin: Over Voltage Protection
R LIM 100K 1 kOVP VCONT = VOVP= 3V
ROVP RLIM
or k OVP VCONT
+ 3V
RLIM 50K
VDS
VOVP
K OVP
N AUX
VoutOVP VDSEC VDOVP
N SEC
GND / SOURCE DRAIN
VDD DRAIN
DOVP ROVP VIPerx5
ZCD
FB BR
Auxiliary
RLIM
winding
110

111. ZCD pin: Power MOSFET turn on
DEGMAGNETIZATION PHASE
VDS
Turn off The Power MOSFET turn on is controlled by the ZCD pin.
GND / SOURCE DRAIN
VZCD VDD DRAIN
DOVP ROVP
VAUX
t
ZCD
VIPERx5
VAUX FB BR
t
RFF
Auxiliary RLIM
VZCD
winding
ARMING LEVEL
TRIGGER LEVEL
ZCD LOWER CLAMP
t
IDRAIN
Steady state operation
t
Turn on DELAY
111

112. POWER Capability and switching frequency
 In quasi resonant Flyback converter the
switching frequency changes with:
 Input Voltage
 Load
Where fT is:
Where fr is:
112

113. BR pin (IC supply)
GND / SOURCE DRAIN
VDD VIPerx5* DRAIN
VIPerx7+
CONT+/ ZCD*
FB BR*+
113

114. BR pin: What you can do?
 To interdict the switching during low input voltage (VIN)
 VIN(OFF) and VIN(ON) thresholds can be separately fixed by the
current hysteresis
 Brownout protection input with hysteresis.
 A voltage below the threshold VBRth shuts down (not latch) the
device and lowers the power consumption.
 Device operation restarts as the voltage exceeds the threshold
VBRth + VBRhyst.
Advantages
 Reduce the RMS current
 Guaranty monotonic output voltage decreasing during the
converter turn off
114

115. BR pin: VIN(ON) & VIN(OFF)
VIN
VINDC
VIN(ON) GND / SOURCE DRAIN
VIN(OFF) VDD VIPERx5 DRAIN
R1
CONT / ZCD
VIPERx7
FSW = 60 KHz FSW = 0 KHz FSW = 60 KHz BR
FB
IBR_hyst
VBR
R2
450 mV
RH RL
VIN OFF VBRth
RL
100 mV
IBR_hyst RH RL
10 A VIN ON VBRth VBR _ HYS RH I HYS
RL
115

116. BR pin: To disable the Brown out
VIN
VIN(ON)
VIN(OFF)
GND / SOURCE DRAIN
FSW = 60 KHz VDD
VIPERx5 DRAIN
VBR
CONT /ZCD VIPERx7
BR
450 mV FB
Brown out
100 mV disable level
IBR_hyst
15 A
116

117. EPT pin (Viperx8 )
GND / SOURCE DRAIN
VDD DRAIN
~
VIPerx8
~
CONT+
~
FB EPT
117

118. EPT pin: What you can do?
 Give extra out power for programmed time
IDLIM = 750mA GND DRAIN
VDD DRAIN
VIPerx8
IDLIM_EPT = 85% IDLIM =650mA CONT
EPT
FB
5uA
IDRAIN> IDLIM_EPT ;5 A charges CEPT and
Vout is regulated CEPT
V (EPT)
VEPT(STOP)
Operations restarts here
VEPT(RESTART)
118

119. 2nd OCP - IC PROTECTION
 Present in Viperx5, Viperx7 & Viperx8
 To latch the power after extra drain current…, upper than IDLIM
 Noise filter with latch after the 2nd event (i.e. during the ESD)
 AUTOMATIC AUTORESTART after the 2nd OCP latch
Advantages
 Protection from SHORT CIRCUIT in secondary diode
 Protection from HEAVY TRANSFORMER SATURATIONS
 System RELIABILITY
IDRAIN
2nd OCP
IDILM
t
TBLANK
119

120. ALTAIR & HVLED
Optoless Current & Voltage Controllers
120

121. Device objective – Standard configuration
 Accurate CC-CV regulation
 Need dedicated CV-CC regulator
 Need secondary components and opto
 Power dissipation on sense resistor
 Expensive solution
121

122. ST - Proposed configuration
 Control of output voltage and current entirely from
primary side
 Save all secondary regulation components (voltage
reference, error amplifiers, optocoupler, sense resistor)
122

123. Technology
800V Avalanche Ruggedness Power MOSFET
in SuperMESH Technology
DRAIN
VCC Out
Out
GND On-Off On/Off
IREF
Gate Gate
ZCD/FB CONTROL
Sense Sense
COMP
CDC
TRIM
DATA
CLOCK
Gnd1
SOURCE
BCD6 controller technology
With OTP (one time programmable) trimming
function available for the end user
123

124. Main electrical parameters – HVLED805
Main Features Pin description
 800V, avalanche rugged power section
 QR current-mode PWM controller in BCD6
technology SO16
 Constant voltage and constant current output
regulation (CV/CC) with no optocoupler
 Optimized for LED
 High performance for stand-by & efficiency
 Integrated protections: 2nd OCP, open loop
protection (brownout) OLP, high OCP  SOURCE
 Automatic auto restart after fault Power section Source
 Vcc
Power MOSFET CONTROLLER
MAIN PARAMETERS controller supply voltage / ICHARGE output current
(SuperMESH) (BCD6S)
Main parameters  GND
Break down voltage [V] 800
controller ground
RDSon [Ohm] 11  ILED
Current loop reference
VDD [V] 11.5 ÷ 23  DMG
Zero Current Detection
FOSC [KHz] Up to 166 kHz
 COMP
Restart time during burst mode( 500us Compensation network
RTHJ-A [°C/W] (1) 80
 DRAIN
Power section Drain
POUT [W] @ 85-265VAC 5
(1) Package SO16N and 100mm2 of Cu

125. Main electrical parameters – ALTAIR05T-800
Main Features Pin description
 800V, avalanche rugged power section SOURCE 1 16 DRAIN
 QR current-mode PWM controller in BCD6 SOURCE 2 15 DRAIN
technology SO16 Vcc 3 14 DRAIN
GND 4
 Constant voltage and constant current output 13 DRAIN
IREF 5 12 N.C.
regulation (CV/CC) with no optocoupler
ZCD/FB 6 11 N.A.
 High performance for stand-by & efficiency COMP 7 10 N.A.
 Integrated protections: 2nd OCP, open loop CDC 8 9 N.A.
protection (brownout) OLP, high OCP
 Automatic auto restart after fault  SOURCE
Power section Source
Power MOSFET CONTROLLER  Vcc
MAIN PARAMETERS
(SuperMESH) (BCD6S)
Main parameters controller supply voltage / ICHARGE output current
Break down voltage [V] 800  GND
controller ground
RDSon [Ohm] 11
 IREF
VDD [V] 11.5 ÷ 23 Current loop reference
 ZCD/FB
FOSC [KHz] Up to 166 kHz Zero Current Detection, Cvregulation, FF
compensation
Restart time during burst mode(1) 500us
 COMP
RTHJ-A [°C/W] (2) 80 Compensation network
POUT [W] @ 85-265VAC 6  CDC
Cable Drop Cpmplensation
(1) Also 125us, 250us and 1ms available  DRAIN
(2) Package SO16N and 100mm2 of Cu Power section Drain

126. Main electrical parameters – ALTAIR04-900
Main Features Pin description
 900V, avalanche rugged power section SOURCE 1 16 DRAIN
 QR current-mode PWM controller in BCD6 SOURCE 2 15 DRAIN
technology SO16 Vcc 3 14 DRAIN
 Constant voltage and constant current output GND 4 13 DRAIN
IREF 5 12
regulation (CV/CC) with no optocoupler N.C.
ZCD/FB 6 11 N.C.
 High performance for stand-by & efficiency
COMP 7 10 N.C.
 Integrated protections: 2nd OCP, open loop N.C. 8 9 N.C.
protection (brownout) OLP, high OCP
 Automatic auto restart after fault  SOURCE
Power section Source
Power MOSFET CONTROLLER  Vcc
MAIN PARAMETERS
(SuperMESH) (BCD6S)
Main parameters controller supply voltage / ICHARGE output current
Break down voltage [V] 900  GND
controller ground
RDSon [Ohm] 16
 IREF
VDD [V] 11.5 ÷ 23 Current loop reference
 ZCD/FB
FOSC [KHz] Up to 166 kHz Zero Current Detection, Cvregulation, FF
compensation
Restart time during burst mode(1) 500us
 COMP
RTHJ-A [°C/W] (2) 50 Compensation network
POUT [W] @ 85-265VAC 5  DRAIN
Power section Drain
(1) Also 125us, 250us and 1ms available
(2) Package SO16N and 100mm2 of Cu

127. Typical load regulation cv/cc: high accuracy
6
High voltage accuracy 5
+/-2.5%
4
Output Voltage [V]
3
2 HV Startup is ON
1
0
0 200 400 600 800 1000 1200
Output Current [mA]
High current accuracy:
+/-5%
127

128. CV Mode – Principe of operations
V aux
GND
An accurate image of the output voltage can be obtained by sampling
the voltage of the auxiliary winding right at the end of transformer’s
demagnetization. We use our proprietary technique to do the job.

129. CC Mode – Principe of operations
T
IP
t
Is
t
Q
t
IC IREF IREF
t
VC
ICREF R
 Valid in DCM only
n R IREF
IOUT  Iout not depend on
2 RSENSE either Vin, Vout or Fsw

130. Layout Recommendations
Viper Family

131. Layout Rules
Some simple rules insure a correct running of
switching power supplies. They may be classified
into two categories:
 To minimize power loops
 Split low level signals and power
Thermal management is important too, consider:
 Copper in Drain pin for thermal dissipation
 Helps for instantaneous thermal peaks
 Dissipates heat from Drain
131

132. Layout Rules
 To minimize power loops:
 The way the switched power current must be carefully analyzed
and the corresponding paths must present the smallest possible
inner loop area. This avoids radiated EMC noises, conducted
EMC noises by magnetic coupling, and provides a better
efficiency by eliminating parasitic inductances, especially on
secondary side.
 To use different tracks for low level signals and power
ones.
 The interferences due to a mixing of signal and power may result
in instabilities and/or anomalous behavior of the device in case of
violent power surge (Input overvoltages, output short circuits...).
132

133. Viper Loops
In case of VIPer, these rules apply as shown:
 Loops that must be minimized:
 C1-T1-U1
 C5-D2-T1
 C7-D1-T1
 C6 must be as close as possible to T1
 C2, ISO1, C3 and C4 use a dedicated track to be
connected directly to the source of the device
133

134. Viper Loops
134

135. Viper Loops Analysis
 Schematic for Loop Analysis
135

136. Loop Analysis
 Layout for Loop Analysis
136

137. Loop A, High Voltage
137

138. Loop B, Low Signals
138

139. Loop C, Small signal GND
139

140. Loop D, Output
140

141. Y Capacitor, Primary & Secondary
 As close as possible to Transformer
141

142. e-DESIGN
142