ST AN2509 Application note

AN2509

Application note

Wide range 400W (+200 V@1.6 A / +75 V@1 A)

L6599-based HB LLC resonant converter

Introduction

This note describes the performances of a 400W reference board, with wide-range mains
operation and power-factor-correction (PFC) and presents the results of its bench
evaluation. The electrical specification refers to a power supply for general purpose
application, with two main output voltages (200 V and 75 V).

The main features of this design are the very low no-load input consumption (<0.5 W) and
the very high global efficiency, better than 90% at full load and n ominal mains v o ltage (115 ­230 V

The circuit consists of three main bloc ks. The first is a front-end PFC pre-re gulator based on
the L6563 PFC controller. The second stage is a multi-resonant half-bridge converter with
two output volta ges of +200 V/300 W a nd 75 V/75 W, whose control is implemented through
the L6599 resonant controller. A further auxiliary flyback converter based on the VIPer12A
off-line primary switcher completes the architecture. This third block, deliv ering a total power
of 7 W on two output voltages (+3.3 V and +5 V), is mainly intended for microprocessor
supply and display power management operations

AC

).

L6599 & L6563 400W demonstration board

April 2007 Rev 3 1/37

www.st.com

Contents AN2509

Contents

1 Main characteristics and circuit description . . . . . . . . . . . . . . . . . . . . . 4

2 Electrical test results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

2.1 Harmonic content measurement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

2.2 Efficiency measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

2.3 Resonant stage operating waveforms . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

2.4 Standby and no-load power consumption . . . . . . . . . . . . . . . . . . . . . . . . 17

2.5 Short-circuit protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

2.6 Overvoltage protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

3 Thermal tests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

4 Conducted emission pre-compliance test . . . . . . . . . . . . . . . . . . . . . . 21

5 Bill of materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

6 PFC coil specification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

6.1 Electrical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

6.2 Mechanical aspect and pin numbering . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

7 Resonant power transformer specification . . . . . . . . . . . . . . . . . . . . . 30

7.1 Electrical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

8 Auxiliary flyback power transformer . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

8.1 Electrical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

9 Board layout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

10 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

11 Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

2/37

AN2509 List of figures

List of figures

Figure 1. PFC pre-regulator electrical diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Figure 2. Resonant converter electrical diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Figure 3. Auxiliary converter electrical diagram. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Figure 4. Compliance to EN61000-3-2 standard for harmonic reduction: full load . . . . . . . . . . . . . . . 9

Figure 5. Compliance to EN61000-3-2 standard for harmonic reduction: 70 W load. . . . . . . . . . . . . . 9

Figure 6. Compliance to JEIDA-MITI standard for harmonic reduction: full load . . . . . . . . . . . . . . . . . 9

Figure 7. Compliance to JEIDA-MITI standard for harmonic reduction: 70 W load . . . . . . . . . . . . . . . 9

Figure 8. Power factor vs. Vin & load. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Figure 9. Total harmonic distortion vs. Vin & load . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Figure 10. Overall efficiency versus output power at nominal mains voltages. . . . . . . . . . . . . . . . . . . 12

Figure 11. Overall efficiency versus input mains voltage at various output power levels . . . . . . . . . . 12

Figure 12. Resonant circuit primary side waveforms at full load . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Figure 13. Resonant circuit primary side waveforms at light load (about 45 W output power) . . . . . . 14

Figure 14. Resonant circuit primary side waveforms at no load condition. . . . . . . . . . . . . . . . . . . . . . 14

Figure 15. Resonant circuit secondary side waveforms: +200 V output . . . . . . . . . . . . . . . . . . . . . . . 15

Figure 16. Resonant circuit secondary side waveforms: +75 V output . . . . . . . . . . . . . . . . . . . . . . . . 15

Figure 17. Low frequency (100 Hz) ripple voltage on +200 V and + 75 V outputs . . . . . . . . . . . . . . . 16

Figure 18. Load transition (0.16 A - 1.6 A) on +200 V output voltage . . . . . . . . . . . . . . . . . . . . . . . . . 16

Figure 19. +200 V output short-circuit waveforms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

Figure 20. Thermal map @115 V
Figure 21. Thermal map at 230 V
Figure 22. Peak measurement on LINE at 115 V
Figure 23. Peak measurement on Neutral at 115 V
Figure 24. Peak measurement on LINE at 230 V
Figure 25. Peak measurement on Neutral at 230 V

Figure 26. Electrical diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

Figure 27. Pin side view. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

Figure 28. Electrical diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

Figure 29. Mechanical aspect and pin numbering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

Figure 30. Winding position on coil former. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

Figure 31. Electrical diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

Figure 32. Auxiliary transformer winding position on coil former . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

Figure 33. Copper tracks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

Figure 34. Thru-hole component placing and top silk screen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

Figure 35. SMT component placing and bottom silk screen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

- full load . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

AC

- full load. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

AC

and full load . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

AC

and full load. . . . . . . . . . . . . . . . . . . . . . . . . . . 21

AC

and full load . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

AC

and full load. . . . . . . . . . . . . . . . . . . . . . . . . . . 22

AC

3/37

Main characteristics and circuit description AN2509

1 Main characteristics and circuit description

● The main characteristics of the SMPS are listed below:

● Universal input mains range: 90 to 264 V

● Output voltages: 200 V @ 1.5 A - 75 V @ 1 A - 3.3 V @ 0.7 A - 5 V @ 1 A

● Mains harmonics: compliance with EN61000-3-2 specifications

● Standby mains consumption: less than 0.5 W @230 V

●

Overall efficiency: better than 87% at full load, 90-264 V

●

EMI: Compliance with EN55022-class B specifications

● Safety: Compliance with EN60950 specifications

● PCB single layer: 132x265 mm, mixed PTH/SMT technologies

The circuit consists of three stages. A front-end PFC pre-regulator implemented by the
controller L6563 (Figure 1), a half-bridge resonant DC/DC conve rter based on the reson ant
controller L6599 (Figure 2), and a 7 W flyback converter intended for standby management
(Figure 3) utilizing the VIPer12A off-line primary switcher.

The PFC stage delivers a stable 400 VDC supply to the do wnstream con v erters (resonant +
flyback) and provides for the reduction of the current harmonics drawn from the mains, in
order to meet the requirements of the Euro pe a n no rm EN61000-3-2 and the JEIDA-MITI
norm for Japan.

- 45 to 65 Hz:

AC

AC

AC

The PFC controller is the L6563 (U1), integrating all functions needed to operate the PFC
and interface the downstream resonant converter. Although this controller chip is designed
for Transition-Mode (TM) operation, where the boost inductor wo rks next to the boundary
between Continuous (CCM) and Discontin uous Conduction Mode (DCM), by adding a
simple external circuit, it can be operated in LM-FOT (line-modulated fixed off-time). This
mode allows for CCM o perat ion, normally achie v ab le with more e x pensiv e contro l chips and
more complex architectures . The LM-F O T mode allows the use of a lo w-cost de vice lik e the
L6563 at a high power level, usually covered by CCM topologies. For a detailed and
complete description of the LM-FOT operating mode see the application note AN1792. The
external components to configure the circuit in LM-FOT mode are: C15, C17, D5, Q3, R14,
R17 and R29.

The power stage of the PFC is a conventional boost converter, connected to the output of
the rectifier bridge through a differential mode filtering cell (C5, C6 and L3) for EMI
reduction. It includes a coil (L4), a diode (D3) and two capacitors (C7 and C8). The boost
switch consists of two power MOSFETs (Q1 and Q2), connected in parallel, which are
directly driven by the L6563 output drive thanks to the high current capability of the IC.

The divider (R30, R31 and R32), connected to MULT pin 3, provides the information of the
instantaneous voltage that is used to modulate the boost current and to derive further
information like the average value of the AC line used by the V

(voltage feed-forward)

FF

function. This function is used to keep the output voltage almost independent of the mains.
The divider (R3, R6, R8, R10 and R11) is dedicated to detecting the output voltage while a
further divider (R5, R7, R9, R16 and R25) is used to protect the circuit in case of voltage
loop failure.

The second stage is an LLC resonant converter, with half-bridge topology implementation,
working in ZVS (zero voltage switching) mode.

4/37

AN2509 Main characteristics and circuit description

The controller is the L6599 integrated circuit that incorporates the necessary functions to
properly drive the two half-bridge MOSFETs b y a 50 % fix ed duty cycle with fixed dead-time,
changing the frequency according to the feedback signal in order to regulate the output
voltages against load and input voltage variations. The main features of the L6599 are a
non-linear soft-start, a current protection mode used to program the hiccup mode timing, a
dedicated pin for sequencing or brown-out (LINE) and a standby pin (STBY) for burst mode
operation at light loads (not used in this design).

The transformer (T1) uses the magne tic integration approach, incorporating the resonant
series and shunt inductances of the LLC resonant tank. Thus, no additional external coils
are needed for the r esonance. F or a detaile d analysis of the LLC r esonant con v erter , please
refer to the application note AN2450.

The secondary side power circuit is configured with center- tap windings and two diodes
rectification for each outpu t (diod es D8A, D8B, D10A, D10B). The two center tap windings
are connected in series on the DC side (r efer to Figure 2). The +75 V rail is connected to
the center tap of the higher voltage winding (the one connected to the anodes of D8A and
D8B diodes). Therefore the higher v oltage windin g only has to provide a v oltage equal to the
difference of the two output voltages: 200 V - 75 V = 125 V. This winding arrangement has
the advantage of a better cross regulation with respect to the case of two completely
separated outputs. F urthermore, due to the fact that the +200 V diodes only have to
withstand a voltage of about 25 0 V (2 x 125 V), inst ead of about 400 V in case of complet ely
separated windings, the designer can select a diode with a lower junction capacitance
minimizing the effect of this capacitance refle ct ed at transformer primary side. This may
affect the behavior of the resonant tank, changing the circuit from LLC to LLCC type, with
the risk that the conv erter, in light-load/n o-load condition ( when the f e edbac k loop increa ses
the operating frequency), can no longer control the output voltage.

The feedbac k loop is implemented b y means of a classical con figuration using a TL431 (U4)
to adjust the current in the optocoupler diode (U3). The optocoupler transistor modu lates the
current from controller Pin 4, so the frequency will change accordingly, thus achieving the
output voltage regulation. Resistors R46 and R54 set the maximum operat ing frequency.

In case of a short circuit, the current entering the primary winding is detected by the lossless
circuit (C34, C39, D11, D12, R43, and R45) and the resulting signal is fed into L6599 Pin 6.
In case of overload, the voltage on Pin 6 exceeds an internal threshold that triggers a
protection sequence via Pin 2, keeping the current flowing in the circuit at a safe level.

The third stage is a small flyback converter based on the VIPer12A, a current mode
controller with integrated power MOSFET, capable of delivering about 7 W total output
power on the output voltages (5 V and 3.3 V). The regulated output voltage is the 3.3V
output and, also in this case, the feedback loop uses the TL431 (U7) and optocoupler (U6)
to control the output volta ge.

This converter is able to operate in the whole mains voltage range, even when the PFC
stage is not working. From the auxiliary winding on the primary side of the flyback
transformer (T2), a voltage Vs is available, intended to supply the other controllers (L6563
and L6599) in addition to the VIPer12A itself.

The PFC stage and the resonant converter can be switched on and off through the circuit
based mainly on components Q7, Q8, D22 and U8, which, depending on the level of the
signal ST-BY, supplies or removes the auxiliary voltage (VAUX) necessary to start-up the
controllers of the PFC and resonant stages. When the AC input voltage is applied to the
power supply, the small flyback converter switches on first. Then, when the ST-BY signal is
asserted low, the PFC p re-regulator becomes oper ative , and last the resonant conv erter can
deliver the output power to the load. Note that if Pin 9 of Connector J3 is left floati ng (no

5/37

Main characteristics and circuit description AN2509

signal ST-BY present), the PFC and resonant converter will not operate, and only +5 V and
+3.3 V supplies are availa ble on the output. In order to enable the +200 V and +75 V
outputs, Pin 9 of Connector J3 must be pulled down to ground.

Figure 1. PFC pre-regulator electrical diagram

Vdc

+400V

C9

2nF2-Y 1

330uF/450V

C8

R2

NTC 2R5-S237

C7

470nF/630V

D3

STTH8R06

1-2

D1

1N5406

L4

PQ40-500uH

5-6

D4

LL4148

Q2

STP12NM50FP

Q1

STP12NM50FP

D6

LL4148

R18

R15

6R8

6R8

R24

0R39

R23

0R39

R22

0R39

R21

0R39

R19

1k0

C18

330pF

Vrect

C6

470nF/630V

L3

DM-51uH-6A

C5

470nF/630V

Vaux

+

-

D2

D15XB60

~

~

C11

2

680nF-X2

Jumper

330nF-X2

470nF-X2

1M5

2nF2-Y2

C10

2nF2-Y2

CON2-IN

C4

Jumper

C3

L1

CM-1.5mH-5A

C2

R1

F1

8A/250V

1

J1

R4

47

C13

10uF/50V

C12

100nF

R6

680kR8680k

R3

680k

R5

Vdc

2M2

R11

R10

R7

2M2

R9

D5

C15

100pF

R14

3k3

R17

C17

15k

U1

L6563

100k

R13

56k

C14

100nF

C16

1uF

2M2

CSCS

LL4148

15k

220pF

GD

VCC

INV

COMP

ZCD

GND

MULTCSVFF

PWM-Latch

R29

1k5

Q3

BC857C

R20

1k0

C21

2nF2

R28

RUN

PWM-STOP

TBO

PFC-OK PWM-LATCH

R16

5k1

LINE

240k

R26

150k

C20

470nF

C19

10nF

R25

30k

C22

10nF

R32

10k

R31

620k

R30

620k

Vrect

6/37

AN2509 Main characteristics and circuit description

Figure 2. Resonant converter electrical diagram

1234567

J2

+200V

L5

T1

8

CON8

C25

22uF/250V

C29

10uH

C30

D8A

T-RE S-ER 49- 400 W

D8B

BYT08P-400

BYT08P-400

C28

47nF/630V

+75V

C38

C35

100uF/250V

JP

100uF/250V

47uF/100V

L6

22uH

D10B

D10A

STTH1002C

STTH1002C

220uF/100V

C37

220uF/100V

R50

56k

R49

56k

R48

56k

R86

C59

R53

C41

D13

R52

470R

47nF

R61

75k

R58

75k

10uF/50V

C-12V

R56

1k0

3k3

U3A

SFH617A-2

2k7

R60

6k2

R59

1k0

C44

47nF

U4

TL431

R43

150

C34

220pF/630V

Vdc

Q5

R33

D7

R88

560k

Q12

BC557

C61

470nF

Q6

STP14NK50Z

0R

R35

47

LL4148

C23

100nF

STP14NK50Z

R39

0R

R40

47

D9

LL4148

C27 100nF

U2

L6599

R36

0R

R34

2k7

C24

470nF

R37

2M2

VBOOT

CSS

C26

OUT

HVG

DELAYCFRFMIN

270pF

R41

Vaux

C32

100nF

R38

47

C31

10uF/50V

NC

LVG

VCC

STBY

ISEN

LINE GND

DIS PFC-STOP

C33

4nF7

R42

10

16k

D11

LL4148

D12

LL4148

R45

100R

C39

1uF0

U3B

C40

10nF

R47

10k

R46

1k5

SFH617A-2

R87

220R

C60

470nF

R54

1k5

LINE

PWM-Latch

7/37

Main characteristics and circuit description AN2509

Q10

BC847C

C54

100nF

U7

TL431

C53

2nF2

U6A

SFH617A-2

U6B

SFH617A-2

Vs

+200V

R67

1k0

SSFB

Vdd D

D

D

D

U5

VIPER-12A

R82

100k

R79

2k2

D15

1N5822

D16

1N5821

D20

BAV103

C56

100nF

C45

1000uF/10V

C47

1000uF/10V

C50

10uF/50V

C46

100uF/10V

C49

100uF/10V

Q9

BC857C

C48

10uF/50V

R76

150k

U8A

SFH617A-2

R75

150k

U8B

SFH617A-2

R74

10k

R77

4k7

D19

C-30V

St-By

D18

B-10V

123456789

10

J3

CON10

R69

0R

Vdc

C52

47nF

R68

22k

C51

100nF

R71

10k

Q8

BC847C

R72

10k

C55

10uF/50V

R66

1k0

T2

T-FLY -AUX-E20

+400V

R70

22R

Vdc

+400V

R83

1M0

R84

150k

C58

10nF

Q11

BC557C

+5Vst -by

R81

30k

R80

30k

+3V3

+5Vst-by

Q7

BC547C

D22

C-15V

L7

33uH

L8

33uH

D17

LL4148

+75V

D21

B-15V

D23

B-15V

R62

47

R64

1k6

C57

1nF0

Vs

Vaux

+5Vst -by

D14

PKC-136

St-By

R73

8k2

Figure 3. Auxiliary converter electrical diagram

8/37

AN2509 Electrical test results

2 Electrical test results

2.1 Harmonic content measurement

The current harmonics drawn from the mains have been measured according to the
European rule EN61000-3-2 Class-D and Japanese rule JEIDA-MITI Class-D, at full load
and 70 W output power, at both nominal input voltages (230 V
in Figure 4 to Figure 7 show that the measured current harmonics are well below the limits
imposed by the regulations , both at full-load and at 70 W load.

and 100 VAC). The graphs

AC

Figure 4. Compliance to EN61000 -3 -2

standard for harmonic reductio n :

10

1

0.1

0.01

0.001

0.0001

full load

Measurements @ 230Vac Full load EN61000-3-2 class D limit s

1234567891011121314151617181920

Harmoni c Order (n)

Figure 6. Compliance to JEIDA-MITI standard

10

for harmonic reduction: full load

Measurements @ 100Vac Full load J EIDA- M ITI c la ss D l im it s

Figure 5. Compliance to EN61000-3-2

standard for harmonic reduction:
70 W load

Measurement s @ 230Vac 70W EN61 000-3-2 cl ass D limits

1

0.1

0.01

0.001

0.0001
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20

Harmoni c Order (n)

Figure 7. Compliance to JEIDA-MITI standard

for harmonic reduction: 70 W load

Measurement s @ 100V ac 70W JEI DA -MIT I cla s s D limits

1

1

0.1

0.01

0.001

0.0001
1234567891011121314151617181920

Harmoni c Order (n)

The Power Factor (PF) and the Total Harmonic Distortion (THD) are reported in Figure 8
and Figure 9. It is evident from the graph that th e PF stays close to unity in the whole mains
voltage range at full load and at half load, while it decreases at high mains at low load
(70 W). The THD has similar behavior, remaining within 25% overall the mains voltage
range and increasing at low load (70 W) at high mains voltage.

0.1

0.01

0.001

0.0001
1234567891011121314151617181920

Harmoni c Orde r (n )

9/37

Electrical test results AN2509

Figure 8. Power factor vs. Vin & load Figure 9. Total harmonic distortion vs. Vin &

PF

1.00

0.98

0.95

0.93

0.90

0.88

0.85
80 120 160 200 240 280

400W
200W
70W

Vin [Vrms]

THD [%]

25.00

20.00

15.00

10.00

5.00

0.00
80 120 160 200 240 280

load

400W
200W
70W

Vin [Vrms]

2.2 Efficiency measurements

Table 1 and Table 2 show the output voltage measurements at the nominal mains voltages

of 115 V
load and at light load operations, the input power is measured using a Yokogawa WT-210
digital power meter. Particular attention has to be paid when measuring input power at full
load in order to avoid measurement errors due to the voltage drop on cables and
connections.

and 230 VAC, with different load condi tions. For all measurements, both at full

AC

Figure 10 shows the overall circuit efficiency, measured at each load condition, at both

nominal input mains voltages of 115 V

and 230 VAC. The values were measured af ter 30

AC

minutes of warm-up at maximum load. The high efficiency of the PFC pre-regulator working
in FOT mode and the very high efficiency of the resonant stage working in ZVS (i.e. with
negligible switching losses), provides for an overall efficiency better than 87% at full load in
the complete mains voltag e r a ng e. This is a significant high value for a two-stage converter ,
especially at low input mains voltage where the PFC conduction losses increase. Even at
lower loads, the efficiency still remains high.

Table 1. Efficiency measurements @VIN = 115 V

+200 V @load(A) +75 V@load(A) +5 V @load(A) +3.3 V@load(A) POUT(W) PIN(W) Eff. %

200.29 1.591 77.77 1.020 4.88 0.975 3.33 0.695 405.06 433.30 93.48%

200.29 1.441 77.78 0.894 4.88 0.975 3.33 0.695 365.23 390.68 93.48%

200.31 1.281 77.78 0.801 4.88 0.975 3.33 0.695 325.97 348.98 93.41%

200.31 1.120 77.79 0.694 4.88 0.975 3.33 0.695 285.41 306.05 93.25%

200.32 0.962 77.79 0.600 4.88 0.502 3.33 0.352 243.00 260.90 93.14%

200.34 0.802 77.80 0.506 4.88 0.502 3.33 0.352 203.66 219.52 92.78%

200.34 0.642 77.80 0.399 4.88 0.502 3.33 0.352 163.28 177.37 92.06%

200.34 0.481 77.81 0.306 4.88 0.502 3.33 0.352 123.80 136.39 90.77%

200.40 0.321 77.83 0.199 4.86 0.144 3.33 0.097 80.84 91.34 88.50%

AC

200.43 0.161 77.83 0.105 4.86 0.146 3.33 0.099 41.48 50.48 82.17%

10/37

AN2509 Electrical test results

Table 2. Efficiency measurements @V

+200 V @load(A) +75 V @load(A) +5 V @load(A) +3.3 V @load(A) POUT(W) PIN(W) Eff. %

200.32 1.593 77.78 1.022 4.88 0.977 3.33 0.695 405.68 449.65 90.22%

200.32 1.442 77.79 0.896 4.88 0.977 3.33 0.695 365.64 404.46 90.40%

200.32 1.282 77.80 0.802 4.88 0.977 3.33 0.695 326.29 360.10 90.61%

200.32 1.120 77.80 0.694 4.88 0.977 3.33 0.695 285.43 314.90 90.64%

200.35 0.962 77.80 0.600 4.88 0.502 3.33 0.351 243.04 267.18 90.96%

200.32 0.802 77.79 0.508 4.88 0.502 3.33 0.351 203.79 224.33 90.84%

200.31 0.641 77.79 0.399 4.88 0.503 3.33 0.351 163.06 180.53 90.32%

200.34 0.480 77.80 0.305 4.88 0.503 3.33 0.351 123.52 138.06 89.47%

200.40 0.321 77.83 0.197 4.86 0.144 3.33 0.097 80.68 91.83 87.86%

200.43 0.160 77.84 0.050 4.86 0.146 3.33 0.099 405.68 49.72 74.42%

= 230 V

IN

AC

The global efficiency at full load has been measured even at the limits of the input voltage
range, with good results:

At VIN = 90 V
At VIN = 264 V

- full load, the efficiency is 87.27%

AC

- full load, the efficiency is 93.49%

AC

Also at light load, at an output power of about 10% of the maximum level, the overall
efficiency is very good, reaching a v alue of about 75% a t nominal main s v oltag es. Figure 11
shows the efficiency measured at various output power levels versus input mains voltage.

The cross regulation of the resonant converter stage is very good as shown in Table 3,
where the +200 V and +75 V output v o ltages are measur ed in different load conditions, with
minimum output current equa l to 10% of maximum current for both the output volta ges.

Table 3. Cross regulation

230 V

AC

200 V load 75 V load 200 V 75 V 200 V 75 V

max max 200.26 77.77 200.32 77.78
max min 200.35 77.92 200.35 77.94

min max 200.35 77.58 200.35 77.58
min min 200.42 77.82 200.45 77.84

no-load no-load 200.76 77.66 200.76 77.65

115 V

AC

11/37

Electrical test results AN2509

Figure 10. Overall efficiency versus output power at nominal mains voltages

230Vac 115Vac

95%

90%

85%

Eff. (%)

80%

75%

70%

0 50 100 150 200 250 300 350 400 450

Output Power (W)

Figure 11. Overall efficiency versus input mains voltage at various output power

levels

400W 200W 70W

Eff[%]

94%
93%
92%
91%
90%
89%
88%
87%
86%
85%

80 120 160 200 240 280

Vin [Vrms]

2.3 Resonant stage operating waveforms

Figure 12 shows some waveforms during steady state operation of the resonant circuit at full

load. The Ch1 waveform is the half-bridge square voltage on Pin 14 of L6599, driving the
resonant circuit. In the picture it is not e vident, but the switching frequency is normally
slightly modulated following the PFC pre-regulator 100-Hz ripple that is rejected by the

12/37

AN2509 Electrical test results

resonant control circuitry. The Ch2 waveform represents the transformer primary current
flowing into the resonant tank. As shown, it has almost a sinusoidal shape. The resonant
tank has been designed (follo wing the pr ocedure present ed in the applica tion note AN2450)
to operate at a resonance frequency of about 120 kHz when the dc input voltage of the half­bridge circuit is at 390 V (that is the nominal output voltage of the PFC stage).

The resonant frequency has been selected at appr oximately 120 kHz in order to have a
good trade-off between transformer losses and dimens ion s.

The resonant tank circuit has been designed in orde r to have a good margin for ZVS
operation, providing good efficiency, while the almost sinusoidal current wavef orm allows for
an extremely low EMI generation.

Figure 12. Resonant circuit primary side waveforms at full load

Ch1: half-bridge square
voltage on pin 14 of L6599

Ch2: resonant tank current

Ch3: low side MOSFET
drive signal

Figure 13 and Figure 14 show the same waveforms as in Figure 12, when the resonant

converter is light-loaded (about 45 W) or not loaded at all. These two graphs demonstrate
the ability of the converter to operate down to zero load, with the output voltages still within
the regulation range.

The resonant tank current has ob viou sly a triangul ar shape and r epresen ts the m agnet izing
current flowing into the transformer primary side. The oscillation superimposed on the tank
current depends on the occurrence of a further resonance due to the parallel of the
inductances at primary side (the series and shunt inductances in the APR (all primary
referred) transformer model presented in AN2450) and the undesired se condary side
capacitance reflected at transformer primary side.

13/37

Electrical test results AN2509

Figure 13. Resonant circuit primary side waveforms at light load (about 45 W outpu t

power)

Ch1: half-bridge square
voltage on pin 14 of L6599

Ch2: resonant tank current

Ch3: low side MOSFET
drive signal

Figure 14. Resonant circuit primary side waveforms at no load condition

Ch1: half-bridge square
voltage on pin 14 of L6599

Ch2: resonant tank current

Ch3: low side MOSFET
drive signal

In Figure 15 and Figure 16, waveforms relevant to the seco ndary side are represented. For

Figure 15, the waveform Ch1 is the voltage at the anode of D8B diode , referenced to

secondary ground, while the waveforms CH2 and CH3 show the current flowing out of the
cathode of D8B and D8A diodes. For Figure 16, the waveform Ch1 is the voltage at the
anode of D10B diode, referenced to secondary ground, while the waveforms CH2 and CH3
show the current flowing out of the cathode of D10B and D10A diodes.

Also these current waveforms, at secondary side, have almost a sine shape, and the total
average value is the output average current.

14/37

AN2509 Electrical test results

Figure 15. Resonant circuit secondary side waveforms: +200 V outpu t

Ch1: anode voltage of diode D8B
Ch2: current flowing out of diode

D8B cathode
Ch3: current flowing out of diode

D8A cathode

Figure 16. Resonant circuit secondary side waveforms: +75 V output

Ch1: anode voltage of diode D10B
Ch2: current flowing out of diode

D10B cathode
Ch3: current flowing out of diode

D10A cathode

Thanks to the adv antages o f t he reso nant converter, t he h igh fr eque ncy no ise on t he o utpu t
voltages is less than 50 mV, while the residual ripple at twice the mains frequency (100 Hz)
is less than 200 mV on +200 V output and less than 100 mV on +75 V output, at maximum
load and worse line condition (90 V

), as shown in Figure 17.

AC

15/37

Electrical test results AN2509

Figure 17. Low frequency (100 Hz) ripple voltage on +200 V and + 75 V outputs

Ch3: +75 V output voltage
ripple at 100 Hz

Ch4: +200 V output voltage
ripple at 100 Hz

Figure 18 shows the dynamic behavior of the converter during a load variation from 10% to

100% on the +200 V output. This figure also high lights the induced eff ect of th is load change
on the PFC pre-regulator output voltage (+400 V on Ch1 track). Both the transitions (from
10% to 100% and from 100% to 10%) are clean and do not show an y prob lem for the output
voltage regulation.

This shows that the proposed architecture is also highly suitable for power supplies
operating with strong load variation without any problems related t o the load regulation.

Figure 18. Load transition (0.16 A - 1.6 A) on +200 V output v oltage

Ch1: PFC output voltage
Ch2: resonant tank current

envelope
Ch4: +200 V output voltage

ripple

16/37

AN2509 Electrical test results

2.4 Standby and no-load power consumption

The board is specifically designed for light load and zero load operations, typical conditions
occurring during Standby or Power-off operations, when no power is requested from the
+200 V and +75 V outputs. Though the resonant converter can operate down to zero load,
some actions are required to k ee p the inpu t power drawn from the mains very low when the
complete system is in this load condition. Thus, when entering this power manageme nt
mode, the ST-BY signal needs to be set high (by the microcontroller of the system). This
forces the PFC pre-regulator and the resonant stage to switch off because the supply
voltage of the two control ICs is no longer present (Figure 3) and only the auxiliary flyback
converter continues working just to supply the microprocessor circuitry.

Table 4 and Table 5 show the measurements of the input power in several light load

conditions at 115 and 230 V
than 0.5 W.

. These tables show that at no-load the input power is less

AC

Table 4. S tandby consumption at VIN = 115 V

+5 V @load(A) +3.3 V @load(A) POUT(W) PIN(W)

5.06 - 0.016 3.33 - 0.110 0.447 0.850

5.00 - 0.016 3.33 - 0.077 0.336 0.693

4.95 - 0.016 3.33 - 0.054 0.259 0.595

4.87 - 0.016 3.33 - 0.021 0.148 0.445

4.50 - 0.000 3.33 - 0.000 0.000 0.220

Table 5. S tandby consumption at VIN = 230 V

+5 V @load(A) +3.3 V @load(A) POUT(W) PIN(W)

5.06 - 0.016 3.33 - 0.110 0.081 1.220

5.00 - 0.016 3.33 - 0.077 0.080 1.045

4.95 - 0.016 3.33 - 0.054 0.079 0.925

4.87 - 0.016 3.33 - 0.021 0.078 0.740

4.50 - 0.000 3.33 - 0.000 0.000 0.480

2.5 Short-circuit protection

AC

AC

The L6599 is equipped with a current sensing input (pin 6, ISEN) and a dedicated
overcurrent management system. The current flowing in the circuit is detected (through the
not dissipative sensing circuit already me ntioned in Section 1, mainly based on a capacitive
divider formed by the resonant capacitor C28 and the capacitor C34, followed by an
integration cell D12, R45, C39) and the signal is fed into the ISEN pin. This is internally
connected to the input of a first comparator, referenced to 0.8 V, and to that of a second
comparator referenced to 1.5 V. If the voltage ex ternally applied to the ISEN pin exceeds

0.8V, the first comparator is tripped causing an internal switch to be turned on discharging
the soft-start capa cito r CSS.

For output short-circuits, this operation results in a nearly constant peak primary current.

17/37

Electrical test results AN2509

The designer can externally program the maximum time (tSH) that the converter is allowed
to run overloaded or under short-circuit conditions. Overloads or shortcircuits lasting less
than t
duration phenomena. If , instead, t

will not cause any other action, hence providing the system with immunity to short

SH

is exceeded, an o verload protection ( OLP) procedure is

SH

activated that shuts do wn the device and, in case of continuous overload/short circuit,
results in continuous intermittent operation with a user-defined duty cycle. This function is
controlled by the DELAY pin 2 of the resonant controller, by means of the capacitor C24 and
the parallel resistor R37 connected to ground. As the voltage o n the ISEN pin e xceeds 0.8 V,
the first OCP comparator, in addition to discharging CSS, turns on an internal current
generator that, via the DELAY pin, charges C24. As the voltage on C24 reaches 3.5 V, the
L6599 stops switching and the internal generator is turned off, so that C24 is slowly
discharged by R37. The IC restarts when the voltage on C24 becomes less than 0.3 V.
Additionally, if the voltage on the ISEN pin reaches 1.5 V for any reason (e.g. transformer
saturation), the second comparator is triggered, the device shuts down an d the operation
resumes after an on-off cycle. Figure 19 illustrates the short-circuit protection sequence
described above. The on-off operation is controlled by the voltage on pin 2 (DELAY),
providing for the hiccup mode of the circuit. Thanks to this control pin, the designer can
select the hiccup mode timing and thus keep the average output current at a safe level.

In order to allow a long soft-start time, that lets the tank current at start-up increase
gradually, a high value capacitor should be connected on the CSS pin. Anyway, values
above 1-2 µF shou ld not be used, oth erwise, during short circuit, the CSS pin internal s witch
will not be able to properly discharge this capacitor and, therefore, the operating frequency
will not increase quickly to the maximum value and the throughput po wer will not be reduced
as desired. To resolve this problem, the circuit based on Q12, C61 and R88 can be used
(see Figure 2) in addition to C23 and R34. The voltage increase across C23, and therefore
the soft-start duration, mostly depends on the C61 capacitor value and on the high gain of
transistor Q12, while, during short circuit, the small value capacitor C23 can be quickly
discharged to push frequency to the maximum programmed v alue.

Figure 19. +200 V output short-circuit waveforms

Ch1: L6599 pin 2 (DELAY)
Ch2: resonant tank current
Ch3: L6599 pin 6 (ISEN)

Ch4: +200 V output voltage

18/37

AN2509 Thermal tests

2.6 Overvoltage protection

Both the PFC pre-regulator and the resonant converter are equipped with their own
overvoltage protection circuit. The PFC controller is internally equipped with a dynamic and
a static overvoltage protection circuit sensing the current flowing through the error amplif ier
compensation network and entering in the COMP pin (#2). When this current reaches about
18 µA, the output voltage of the multiplier is forced to decrease, thus reducing the energy
drawn from the mains . If the current exceeds 20 µA, the OVP is triggered (Dynamic OVP),
and the external power tr ansistor is s witch ed off until th e current falls approximately below 5
µA. However, if the overvoltage persists (e.g. in case the load is completely disconnected),
the error amplifier will eventually saturate lo w , triggering an internal comparator (Static OVP)
that keeps the external power s witch t urned off until th e ou tput voltage comes back close to
the regulated value.

Moreover, in the L6563 there is an additional protection against loop failures using an
additional divider (R5, R7, R9, R16 and R25) connected to a dedica ted pin (PFC_OK, Pin 7)
protecting the circuit in case of loop failures, disconnection or deviation from the nominal
value of the feedback loop divider. The PFC output voltage is always under control and if a
fault condition is detected, the PFC_OK circuitry latches the PFC operation and using the
PWM_LATCH pin 8, it also latches the L6599 via the DIS pin of the resonant controller.

The OVP circuit (see Figure 3) for the output voltages of the resonant converter uses
resistive dividers (R75, R76, R80, R81, R82) and the zener diodes D21 and D23 to se nse
the +200 V and +75 V outputs. If the sensed voltage exceeds the threshold imposed by
either zener diodes plus the VBE of Q10, the transistor Q9 starts conducting and the
optocoupler U8 opens Q7, so that the VAUX supply voltage of the controller ICs L6563 and
L6599 is no longer available. This state is latched until a mains voltage recycle occurs.

3 Thermal tests

In order to check the design reliability, a thermal mapping by an IR Camera wa s performed.

Figure 20 and Figure 21 show the thermal measurements of the board, component side, at

nominal input voltage. The correlation between measurement points and comp onents is
indicated for both diagrams in Table 6.

All other board components work well within the temperature limits, assuring a reliable long
term operation of the power supply.

Note that the temperatures of L4 and T1 have been measured both on the ferrite core (Fe)
and on the copper winding (Cu).

Table 6. Key components temperature at nominal voltages and full load

Point Item 230 V

A D2 40,3°C 47,6°C
B L4-(FE) 44,2°C 50,5°C
C L4-(CU) 46,0°C 55,5°C
D Q1 44,5°C 53,4°C
E R2 63,5°C 73,0°C

AC

115 V

AC

19/37

Thermal tests AN2509

Table 6. Key components temperature at nominal voltages and full load

Point Item 230 V

F D3 46,1°C 51,0°C
G C8 39,3°C 40,1°C
H Q6 51,4°C 52,8°C

I T1-(CU) 63,7°C 62,6°C

J T1-(FE) 51,3°C 49,6°C

K U5 53,2°C 53,4°C

L D14 51,8°C 52,3°C
M C38 39,4°C 38,5°C
N C45 36,1°C 35,7°C
O D8A 44,5°C 44,9°C
P R22 41,4°C 55,6°C
Q D15 43,3°C 43,5°C
R D16 42,6°C 42,1°C
S T2 43,3°C 43,6°C

Figure 20. Thermal map @115 VAC - full load

AC

115 V

AC

Figure 21. Thermal map at 230 V

20/37

AC

- full load

AN2509 Conducted emission pre-compliance test

4 Conducted emission pre-compliance test

The measurements have been taken in peak detection mode, both on LINE and on Neutral
at nominal input mains and at full load. The limits indicated on the following diagrams refer
to the EN55022 Class- B specifications (the higher limit curve is the quasi-peak limit while
the lower curve is the average limit) and the measurements show that the PSU emission is
well below the maximum allowed limit.

Figure 22. Peak measurement on LINE at 115 V

Figure 23. Peak measurement on Neutral at 115 V

AC

and full load

and full load

AC

21/37

Conducted emission pre-compliance test AN2509

Figure 24. Peak measurement on LINE at 230 VAC and full load

Figure 25. Peak measurement on Neutral at 230 V

and full load

AC

22/37

AN2509 Bill of materials

5 Bill of materials

Table 7. Bill of materials

Item Part Description Supplier

C2 470 nF-X2 275
C3 330 nF-X2 275
C4 680 nF-X2 275
C5 470 nF/630 V POLYPROPYLENE CAPACITOR HIGH RIPPLE MKP R71 ARCOTRONICS - EPCOS
C6 470 nF/630 V POLYPROPYLENE CAPACITOR HIGH RIPPLE MKP R71 ARCOTRONICS - EPCOS
C7 470 nF/630 V POLYPROPYLENE CAPACITOR HIGH RIPPLE MKP R71 ARCOTRONICS - EPCOS
C8 330 µF/450 V ALUMINIUM ELCAP USC SERIES 85 DEG SNAP-IN RUBYCON

C9 2nF2-Y1 400
C10 2nF2-Y1 250
C11 2nF2-Y1 250
C12 100 nF 50 V 1206 SMD CERCAP GENERAL PURPOSE BC COMPONENTS
C13 10 µF/50 V ALUMINIUM ELCAP GENERAL PURPOSE 85 DEG RUBYCON
C14 100 nF 50 V 1206 SMD CERCAP GENERAL PURPOSE BC COMPONENTS
C15 100 pF 100 V 0805 SMD CERCAP GENERAL PURPOSE BC COMPONENTS
C16 1 µF 25 V 1206 SMD CERCAP GENERAL PURPOSE BC COMPONENTS
C17 220 pF 100 V 0805 SMD CERCAP GENERAL PURPOSE BC COMPONENTS
C18 330 pF 100 V 0805 SMD CERCAP GENERAL PURPOSE BC COMPONENTS
C19 10 nF 100 V 0805 SMD CERCAP GENERAL PURPOSE BC COMPONENTS
C20 470 nF 50 V 1206 SMD CERCAP GENERAL PURPOSE BC COMPONENTS

V

X2 SAFETY CAPACITOR MKP R46 ARCOTRONICS

AC

V

X2 SAFETY CAPACITOR MKP R46 ARCOTRONICS

AC

V

X2 SAFETY CAPACITOR MKP R46 ARCOTRONICS

AC

V

Y1 SAFETY CERAMIC DISK CAPACITOR MURATA

AC

V

Y1 SAFETY CERAMIC DISK CAPACITOR MURATA

AC

V

Y1 SAFETY CERAMIC DISK CAPACITOR MURATA

AC

C21 2nF2 100 V 1206 SMD CERCAP GENERAL PURPOSE BC COMPONENTS
C22 10 nF 100 V 0805 SMD CERCAP GENERAL PURPOSE BC COMPONENTS
C23 100 nF 50 V 1206 SMD CERCAP GENERAL PURPOSE BC COMPONENTS
C24 470 nF 25 V 1206 SMD CERCAP GENERAL PURPOSE BC COMPONENTS
C25 22 µF/250 V ALUMINIUM ELCAP YXF SERIES 105 DEG RUBYCON
C26 270 pF 100 V 0805 SMD CERCAP GENERAL PURPOSE BC COMPONENTS
C27 100 nF 50 V 1206 SMD CERCAP GENERAL PURPOSE BC COMPONENTS
C28 47 nF/630 V POLYPROPYLENE CAPACITOR HIGH RIPPLE PHE450 RIFA-EVOX
C29 100 µF/250 V ALUMINIUM ELCAP YXF SERIES 105 DEG RUBYCON
C30 100 µF/250 V ALUMINIUM ELCAP YXF SERIES 105 DEG RUBYCON
C31 10 µF/50 V ALUMINIUM ELCAP GENERAL PURPOSE 85 DEG RUBYCON
C32 100 nF 50 V 1206 SMD CERCAP GENERAL PURPOSE BC COMPONENTS
C33 4nF7 100 V 1206 SMD CERCAP GENERAL PURPOSE BC COMPONENTS

23/37

Bill of materials AN2509

Table 7. Bill of materials (continued)

Item Part Description Supplier

C34 220 pF/630 V POLYPROPYLENE CAPACITOR HIGH RIPPLE PFR RIFA-EVOX
C35 47 µF/100 V ALUMINIUM ELCAP YXF SERIES 105 DEG RUBYCON
C37 220 µF/100 V ALUMINIUM ELCAP YXF SERIES 105 DEG RUBYCON
C38 220 µF/100 V ALUMINIUM ELCAP YXF SERIES 105 DEG RUBYCON
C39 1 µF0 25 V 1206 SMD CERCAP GENERAL PURPOSE BC COMPONENTS
C40 10 nF 100 V 1206 SMD CERCAP GENERAL PURPOSE BC COMPONENTS
C41 10 µF/50 V ALUMINIUM ELCAP GENERAL PURPOSE 85 DEG RUBYCON
C44 47 nF 100V 1206 SMD CERCAP GENERAL PURPOSE BC COMPONENTS
C45 1000 µF/10 V ALUMINIUM ELCAP YXF SERIES 105 DEG RUBYCON
C46 100 µF/10 V ALUMINIUM ELCAP YXF SERIES 105 DEG RUBYCON
C47 1000 µF/10 V ALUMINIUM ELCAP YXF SERIES 105 DEG RUBYCON
C48 10 µF/50 V ALUMINIUM ELCAP GENERAL PURPOSE 85 DEG RUBYCON
C49 100 µF/10 V ALUMINIUM ELCAP YXF SERIES 105 DEG RUBYCON
C50 10 µF/50 V ALUMINIUM ELCAP GENERAL PURPOSE 85 DEG RUBYCON
C51 100 nF 100 V 0805 SMD CERCAP GENERAL PURPOSE BC COMPONENTS
C52 47 nF 100 V 0805 SMD CERCAP GENERAL PURPOSE BC COMPONENTS
C53 2nF2 100 V 0805 SMD CERCAP GENERAL PURPOSE BC COMPONENTS
C54 100 nF 50 V 1206 SMD CERCAP GENERAL PURPOSE BC COMPONENTS
C55 10 µF/50 V ALUMINIUM ELCAP GENERAL PURPOSE 85 DEG RUBYCON
C56 100 nF 50 V 1206 SMD CERCAP GENERAL PURPOSE BC COMPONENTS
C57 1nF0 100 V 0805 SMD CERCAP GENERAL PURPOSE BC COMPONENTS
C58 10 nF 50 V X7R STANDARD CERAMIC CAPA CITOR BC COMPONENTS
C59 47 nF/250 V POLCAP PHE426 SERIES RIFA-EVOX
C60 470 nF 25 V 1206 SMD CERCAP GENERAL PURPOSE VISHAY
C61 470 nF 50 V CERCAP X7R BC COMPONENTS

D1 1N5406 GENERAL PURPOSE RECTIFIER VISHAY

D2 D15XB60 SINGLE PHASE BRIDGE RECTIFIER SHINDENGEN

D3 STTH8R06 TO220FP ULTRAFAST HIGH VOLTAGE RECTIFIER STMicroelectronics

D4 LL4148 MINIMELF FAST SWITCHING DIODE VISHAY

D5 LL4148 MINIMELF FAST SWITCHING DIODE VISHAY

D6 LL4148 MINIMELF FAST SWITCHING DIODE VISHAY

D7 LL4148 MINIMELF FAST SWITCHING DIODE VISHAY

D8A BYT08P-400 TO220FP ULTRAFAST HIGH VOLTAGE RECTIFIER STMicroelectronics
D8B BYT08P-400 TO220FP ULTRAFAST HIGH VOLTAGE RECTIFIER STMicroelectronics

D9 LL4148 MINIMELF FAST SWITCHING DIODE VISHAY

24/37

AN2509 Bill of materials

Table 7. Bill of materials (continued)

Item Part Description Supplier

D10A STTH1002C TO220FP ULTRAFAST MEDIUM VOLTAGE RECTIFIER STMicroelectronics
D10B STTH1002C TO220FP ULTRAFAST MEDIUM VOLTAGE RECTIFIER STMicroelectronics

D11 LL4148 MINIMELF FAST SWITCHING DIODE VISHAY
D12 LL4148 MINIMELF FAST SWITCHING DIODE VISHAY
D13 C-12V BZV55-C SERIES ZENER DIODE VISHAY
D14 PKC-136 PEAK CLAMP TRANSIL STMicroelectronics
D15 1N5822 POWER SCHOTTKY RECTIFIER STMicroelectronics
D16 1N5821 POWER SCHOTTKY RECTIFIER STMicroelectronics
D17 LL4148 MINIMELF FAST SWITCHING DIODE VISHAY
D18 B-10 V BZV55-B SERIES ZENER DIODE VISHAY
D19 C-30 V BZV55-C SERIES ZENER DIODE VISHAY
D20 BAV103 GENERAL PURPOSE DIODE VISHAY
D21 B-15 V BZV55-B SERIES ZENER DIODE VISHAY
D22 C-15 V BZV55-C SERIES ZENER DIODE VISHAY
D23 B-15 V BZV55-B SERIES ZENER DIODE VISHAY

F1 8A/250 V T TYPE FUSE 5X20 HIGH CAPABILITY & FUSEHOLDER WICKMANN
J1 CON2-IN 3 PINS CONN. (CENTRAL REMOVE) P 3.96 KK SERIES MOLEX
J2 CON8 8 PINS CONNECTOR P 3.96 KK SERIES MOLEX
J3 CON10 10 PINS CONNECTOR P 2.54 MTA SERIES AMP
L1 CM-1.5 mH-5 A LFR2205B SERIES COMMON MODE INDUCTOR DELTA

L2 CM-10 mH-5 A

L3 DM-51 µH-6 A LSR2306-1 DIFF. MODE TOROIDAL INDUCTOR DELTA
L4 PQ40-500 µH 86H-5410B BOOST INDUCTOR DELTA
L5 10 µH ELC08 DRUM CORE INDUCTOR PANASONIC
L6 22 µH ELC08 DRUM CORE INDUCTOR PANASONIC
L7 33 µH ELC08 DRUM CORE INDUCTOR PANASONIC

L8 33 µH ELC08 DRUM CORE INDUCTOR PANASONIC
Q1 STP12NM50FP TO220FP N-CHANNEL POWER MOSFET STMicroelectronics
Q2 STP12NM50FP TO220FP N-CHANNEL POWER MOSFET STMicroelectronics
Q3 BC857C SOT23 SMALL SIGNAL PNP TRANSISTOR STMicroelectronics
Q5 STP14NK50Z TO220FP N-CHANNEL POWER MOSFET STMicroelectronics
Q6 STP14NK50Z TO220FP N-CHANNEL POWER MOSFET STMicroelectronics

TF3524 SERIES COMMON MODE TOROIDAL

INDUCTOR

TDK

Q7 BC547C TO92 SMALL SIGNAL PNP TRANSISTOR STMicroelectronics
Q8 BC847C SOT23 SMALL SIGNAL PNP TRANSISTOR STMicroelectronics

25/37

Bill of materials AN2509

Table 7. Bill of materials (continued)

Item Part Description Supplier

Q9 BC857C SOT23 SMALL SIGNAL PNP TRANSISTOR STMicroelectronics

Q10 BC847C SOT23 SMALL SIGNAL NPN TRANSISTOR STMicroelectronics
Q11 BC547C TO92 SMALL SIGNAL PNP TRANSISTOR STMicroelectronics

R1 1M5 VR25 TYPE HIGH VOLTAGE RESISTOR BC COMPONENTS
R2 NTC 2R5-S237 NTC RESISTOR 2R5 S237 SERIES EPCOS
R3 680 k 1206 SMD STANDARD FILM RES 1/4 W 5% 200 ppm/°C BC COMPONENTS
R4 47 0805 SMD STANDARD FILM RES 1/8 W 5% 200 ppm/°C BC COMPONENTS
R5 2M2 1206 SMD STANDARD FILM RES 1/4 W 1% 100 ppm/°C BC COMPONENTS
R6 680 k 1206 SMD STANDARD FILM RES 1/4 W 5% 200 ppm/°C BC COMPONENTS
R7 2M2 1206 SMD STANDARD FILM RES 1/4 W 1% 100 ppm/°C BC COMPONENTS
R8 680 k 1206 SMD STANDARD FILM RES 1/4 W 5% 200 ppm/°C BC COMPONENTS
R9 2M2 1206 SMD STANDARD FILM RES 1/4 W 1% 100 ppm/°C BC COMPONENTS

R10 100 k 0805 SMD STANDARD FILM RES 1/8 W 5% 200 ppm/°C BC COMPONENTS
R11 15 k 0805 SMD STANDARD FILM RES 1/8 W 5% 200 ppm/°C BC COMPONENTS
R13 56 k 1206 SMD STANDARD FILM RES 1/8 W 5% 200 ppm/°C BC COMPONENTS
R14 3k3 0805 SMD STANDARD FILM RES 1/8 W 1% 100 ppm/°C BC COMPONENTS
R15 6R8 0805 SMD STANDARD FILM RES 1/8 W 5% 200 ppm/°C BC COMPONENTS
R16 5k1 1206 SMD STANDARD FILM RES 1/4 W 1% 100 ppm/°C BC COMPONENTS
R17 15 k 0805 SMD STANDARD FILM RES 1/8 W 1% 100 ppm/°C BC COMPONENTS
R18 6R8 0805 SMD STANDARD FILM RES 1/8 W 5% 200 ppm/°C BC COMPONENTS
R19 1K0 0805 SMD STANDARD FILM RES 1/8 W 5% 200 ppm/°C BC COMPONENTS
R20 1k0 STANDARD METAL FILM RES 1/4 W 5% 200 ppm/°C BC COMPONENTS
R21 0R39 PR02 POWER RESISTOR BC COMPONENTS
R22 0R39 PR02 POWER RESISTOR BC COMPONENTS
R23 0R39 PR02 POWER RESISTOR BC COMPONENTS
R24 0R39 PR02 POWER RESISTOR BC COMPONENTS
R25 30 k 0805 SMD STANDARD FILM RES 1/8 W 1% 100 ppm/°C BC COMPONENTS
R26 150 k 1206 SMD STANDARD FILM RES 1/8 W 5% 200 ppm/°C BC COMPONENTS
R28 240 k 0805 SMD STANDARD FILM RES 1/8 W 5% 200 ppm/°C BC COMPONENTS
R29 1k5 0805 SMD STANDARD FILM RES 1/8 W 5% 200 ppm/°C BC COMPONENTS
R30 620 k 1206 SMD STANDARD FILM RES 1/4 W 5% 200 ppm/°C BC COMPONENTS
R31 620 k 1206 SMD STANDARD FILM RES 1/4 W 5% 200 ppm/°C BC COMPONENTS
R32 10 k 0805 SMD STANDARD FILM RES 1/8 W 5% 200 ppm/°C BC COMPONENTS
R33 0R 0805 SMD STANDARD FILM RES 1/8 W BC COMPONENTS
R34 2k7 0805 SMD STANDARD FILM RES 1/8 W 5% 200 ppm/°C BC COMPONENTS

26/37

AN2509 Bill of materials

Table 7. Bill of materials (continued)

Item Part Description Supplier

R35 47 0805 SMD STANDARD FILM RES 1/8 W 5% 200 ppm/°C BC COMPONENTS
R36 0R 0805 SMD STANDARD FILM RES 1/8 W BC COMPONENTS
R37 2M2 0805 SMD STANDARD FILM RES 1/8 W 5% 200 ppm/°C BC COMPONENTS
R38 47 STANDARD METAL FILM RES 1/4 W 5% 200 ppm/°C BC COMPONENTS
R39 0R 0805 SMD STANDARD FILM RES 1/8 W BC COMPONENTS
R40 47 0805 SMD STANDARD FILM RES 1/8 W 5% 200 ppm/°C BC COMPONENTS
R41 16 k 0805 SMD STANDARD FILM RES 1/8 W 1% 100 ppm/°C BC COMPONENTS
R42 10 1206 SMD STANDARD FILM RES 1/8 W 5% 200 ppm/°C BC COMPONENTS
R43 150 1206 SMD STANDARD FILM RES 1/4 W 5% 200 ppm/°C BC COMPONENTS
R45 82R 1206 SMD STANDARD FILM RES 1/4 W 1% 100 ppm/°C BC COMPONENTS
R46 1k5 0805 SMD STANDARD FILM RES 1/8 W 5% 200 ppm/°C BC COMPONENTS
R47 10 k 1206 SMD STANDARD FILM RES 1/8 W 5% 200 ppm/°C BC COMPONENTS
R48 56 k 1206 SMD STANDARD FILM RES 1/4 W 5% 200 ppm/°C BC COMPONENTS
R49 56 k 1206 SMD STANDARD FILM RES 1/4 W 5% 200 ppm/°C BC COMPONENTS
R50 56 k 1206 SMD STANDARD FILM RES 1/4 W 5% 200 ppm/°C BC COMPONENTS
R52 3k3 0805 SMD STANDARD FILM RES 1/8 W 5% 200 ppm/°C BC COMPONENTS
R53 75 k 1206 SMD STANDARD FILM RES 1/4 W 1% 100 ppm/°C BC COMPONENTS
R54 1k5 0805 SMD STANDARD FILM RES 1/8 W 5% 200 ppm/°C BC COMPONENTS
R56 1k0 0805 SMD STANDARD FILM RES 1/8 W 5% 200 ppm/°C BC COMPONENTS
R58 75 k 1206 SMD STANDARD FILM RES 1/4 W 1% 100 ppm/°C BC COMPONENTS
R59 1k0 0805 SMD STANDARD FILM RES 1/8 W 5% 200 ppm/°C BC COMPONENTS
R60 6k2 0805 SMD STANDARD FILM RES 1/8 W 1% 100 ppm/°C BC COMPONENTS
R61 2k7 0805 SMD STANDARD FILM RES 1/8 W 1% 100 ppm/°C BC COMPONENTS
R62 47 0805 SMD STANDARD FILM RES 1/8 W 5% 200 ppm/°C BC COMPONENTS
R64 1k6 0805 SMD STANDARD FILM RES 1/8 W 1% 100 ppm/°C BC COMPONENTS
R66 1k0 0805 SMD STANDARD FILM RES 1/8 W 5% 200 ppm/°C BC COMPONENTS
R67 1k0 0805 SMD STANDARD FILM RES 1/8 W 5% 200 ppm/°C BC COMPONENTS
R68 22 k 0805 SMD STANDARD FILM RES 1/8 W 5% 200 ppm/°C BC COMPONENTS
R69 0R 0805 SMD STANDARD FILM RES 1/8 W 5% 200 ppm/°C BC COMPONENTS
R70 22R 0805 SMD STANDARD FILM RES 1/8 W 5% 200 ppm/°C BC COMPONENTS
R71 10 k 0805 SMD STANDARD FILM RES 1/8 W 5% 200 ppm/°C BC COMPONENTS
R72 10 k 0805 SMD STANDARD FILM RES 1/8 W 5% 200 ppm/°C BC COMPONENTS
R73 8k2 0805 SMD STANDARD FILM RES 1/8 W 5% 200 ppm/°C BC COMPONENTS
R74 10 k 0805 SMD STANDARD FILM RES 1/8 W 5% 200 ppm/°C BC COMPONENTS
R75 150 k 1206 SMD STANDARD FILM RES 1/4 W 1% 100 ppm/°C BC COMPONENTS

27/37

Bill of materials AN2509

Table 7. Bill of materials (continued)

Item Part Description Supplier

R76 150 k 1206 SMD STANDARD FILM RES 1/4 W 1% 100 ppm/°C BC COMPONENTS
R77 4k7 0805 SMD STANDARD FILM RES 1/8 W 1% 100 ppm/°C BC COMPONENTS
R79 2k2 0805 SMD STANDARD FILM RES 1/8 W 5% 200 ppm/°C BC COMPONENTS
R80 30 k 0805 SMD STANDARD FILM RES 1/8 W 1% 100 ppm/°C BC COMPONENTS
R81 30 k 0805 SMD STANDARD FILM RES 1/8 W 1% 100 ppm/°C BC COMPONENTS
R82 100 k 1206 SMD STANDARD FILM RES 1/4 W 1% 100 ppm/°C BC COMPONENTS
R83 1M0 VR25 TYPE HIGH VOLTAGE RESISTOR BC COMPONENTS
R84 150 k STANDARD METAL FILM RES 1/4 W 5% 200 ppm/°C BC COMPONENTS
R86 470R STANDARD METAL FILM RES 1/4 W 5% 200 ppm/°C BC COMPONENTS
R87 220R STANDARD METAL FILM RES 1/4 W 5% 200 ppm/°C BC COMPONENTS
R88 560 K STANDARD METAL FILM RES 1/4 W 5% 200 ppm/°C BC COMPONENTS

T-RES-ER49-

T1

T2 T-FLY-AUX-E20 86A-6079-R TYPE FLYBACK TRANSF. E20 CORE DELTA
U1 L6563 ADVANCED TRANSITION MODE PFC CONTROLLER STMicroelectronics

400W

86H-5408B TYPE RESONANT TRANSFORMER ER49 DEL TA

U2 L6599 HIGH VOLTAGE RESONANT CONTROLLER STMicroelectronics
U3 SFH617A-2 63-125% CTR SELECTION OPTOCOUPLER STMicroelectronics
U4 TL431 TO92 PROGR. SHUNT VOLTAGE REGULATOR STMicroelectronics
U5 VIPER12A LOW POWER OFF LINE SMPS PRIMARY SWITCHER STMicroelectronics
U6 SFH617A-2 63-125% CTR SELECTION OPTOCOUPLER INFINEON
U7 TL431 TO92 PROGR. SHUNT VOLTAGE REGULATOR STMicroelectronics
U8 SFH617A-2 63-125% CTR SELECTION OPTOCOUPLER INFINEON

Note: Q9 and R72: mounted by reworking on PCB

Q11, Q12, R83, R84, R86, R87, R88, C58, C59, C60 and C61: added by reworking on PCB

28/37

AN2509 PFC coil specification

6 PFC coil specification

● Application type: consumer, home appliance

● Inductor type: open

● Coil former: vertical type, 6+6 pins

● Max. temp. rise: 45 °C

● Max. operating ambient temp.: 60 °C

6.1 Electrical characteristics

● Converter topology: FOT PFC Preregulator

● Core type: PQ40-30 material grade PC44 or equivalent

● Max operating freq: 100 KHz

● Primary inductance: 500 µH ±10% @1 KHz-0.25 V (see Note: 1)

● Primary RMS current: 4.75 A

Note: 1 Measured between pins 2-3 and 10-11.

Figure 26. Electrical diagram

2 The auxiliary winding is not used in this design, but is foreseen for another application.

Table 8. Winding characteristics

Start PINS End PINS

11 8 5 (spaced) Single Ø 0.28 mm Bottom

5 - 6 1 - 2 65 Multistrand – G2 Litz Ø 0.2 mm x 30 Top

Turn

number

Wire type Wire diameter Notes

6.2 Mechanical aspect and pin numbering

● Maximum height from PCB: 45 mm

● Cut pins: 9-12

● Pin distance: 5 mm

● Row distance: 45.5 mm

● External copper shield 15 x 0.05 (mm) connected to pin 11 by tinned wire

29/37

Resonant power transformer specification AN2509

Figure 27. Pin side view

● Manufacturer: DELTA ELECTRONICS

● P/N: 86H-5410

7 Resonant power transformer specification

● Application type: consumer, home appliance

● Transformer type: open

● Coil former: horizontal type, 7+7 pins, 2 slots

● Max. temp. rise: 45 °C

● Max. operating ambient temp.: 60 °C

● Mains insulation: ACC. with EN60065

7.1 Electrical characteristics

● Converter topology: half-bridge, resonant

● Core type: ER49 - PC44 or equivalent

● Min. operating frequency: 75 Khz

● Typical operating freq: 120 KHz

● Primary inductance: 240 µH ±10% @1 KHz - 0.25 V [see Note 1]

● Leakage inductance: 40 µH ±10% @1 KHz - 0.25 V [see Note 1] - [see Note 2]

Note: 1 Measured between pins 1-3

2 Measured between pins 1-3 with the secondary windings shorted

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AN2509 Resonant power transformer specification

Figure 28. Electrical diagram

14

SEC. A

13

1

PRIM.

3

SEC. B

12

11

SEC. C

10

9

SEC. D

8

Table 9. Winding characteristics

Pins Winding RMS current N° turns Wire type

1 - 3 PRIMARY 2.90 A
14 - 13 SEC. A
13 - 12 SEC. B
11 - 10 SEC. C

9 - 8 SEC. D

1. Secondary windings A and B must be wound in parallel

2. Secondary windings C and D must be wound in parallel

(1)
(1)
(2)
(2)

RMS

1.7 ARMS 11 Litz Ø 0.2 mm x 10

1.7 ARMS 11 Litz Ø 0.2 mm x 10

1.15 ARMS 7 Litz Ø 0.2 mm x 20

1.15 ARMS 7 Litz Ø 0.2 mm x 20

19 Litz Ø 0.2 mm x 20

Figure 29. Mechanical aspect and pin numbering

Note: Cut PIN 7

● Manufacturer: DELTA ELECTRONICS

● P/N: 86H-5408

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Auxiliary flyback power transformer AN2509

Table 10. Mechanical dimensions

ABCDEF

Dimensions

(mm)

39.0 max 3.5 ± 0.5 41.6 ± 0.4 51 max 7.0 ± 0.2 51.5 max

Figure 30. Winding position on coil former

PRIMARY

SECONDARY

8 Auxiliary flyback power transformer

● Application type: consumer, home appliance

● Transformer type: open

● Winding type: layer

● Coil former: horizontal type, 4+5 pins

● Max. temp. rise: 45 °C

● Max. operating ambient temp.: 60 °C

● Mains insulation: ACC. with EN60065

COIL FORMER

8.1 Electrical characteristics

● Converter topology: flyback, DCM/CCM mode

● Core type: E20 - N67 or equivalent

● Operating frequency: 60 Khz

● Primary inductance: 4.20 mH ±10% @1 KHz - 0.25 V [see Note 1]

● Leakage inductance: 50 µH MAX @100 KHz - 0.25 V [see Note 2]

● Max. PEAK primary current: 0.38 Apk

● RMS primary curre n t: 0. 2 A

Note: 1 Measured between pins 4-5

2 Measured between pins 4-5 with secondary windings shorted

32/37

RMS

AN2509 Auxiliary flyback power transformer

A

Figure 31. Electrical diagram

5

PRIM

4

2

UX

1

● Manufacturer: DELTA ELECTRONICS

● P/N: 86A - 6079 - R

6

+5V

7

8

+3.3V

10

Table 11. Winding characteristics

Pins: start - end Winding RMS current N° turns Wire type

4 - 5 PRIMARY 0.2 A
2 - 1 AUX 0.05 A

8- 10 3.3 V 1.2 A

6 - 7 5 V 1 A

RMS

RMS

RMS

RMS

140 G2 - Ø 0.25 mm

29 G2 - Ø 0.25 mm

7 TIW Ø 0.75 mm
3 TIW Ø 0.75 mm

Figure 32. Auxiliary transformer winding position on coil former

INSULATING TAPE

COIL FORMER

3.3V / 5V
AUX

PRIMARY

33/37

Board layout AN2509

9 Board layout

Figure 33. Copper tracks

34/37

AN2509 Board layout

Figure 34. Thru-hole component placing and top silk screen

Figure 35. SMT component placing and bottom silk screen

35/37

References AN2509

10 References

1. "L6563/L6563A advanced transition-mode PFC controller" Datasheet

2. "Design of Fixed-Off-Time-Controlled PFC Pre-regulators with the L6562", AN1792

3. "L6599 high-voltage resonant controller" Datasheet

4. "LLC resonant half-bridge converter design guideline", AN2450

11 Revision history

Table 12. Revision history

Date Revision Changes

13-Mar-2007 1 First issue
20-Mar-2007 2 Minor text changes

23-Apr-2007 3

– Cross references updated
– Table 7: Bill of materials modified

36/37

AN2509

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