dm00029732

AN3407
Application note
Resonant driver for LED SMPS demonstration board
based on the L6585DE
Introduction
This application note describes the performance of a 100 W LED switched-mode power
supply (SMPS). The L6585DE embeds a high-performance transition mode (TM) power
factor correction (PFC) controller, half-bridge (HB) controller and all the relevant drivers
necessary to build a combo IC. The L6585DE embeds a wide range of features to provide
an energy-saving and cost-effective solution for the LED SMPS demonstration board
(STEVAL-ILL038V1).
Previous dedicated ICs for LED SMPS applications allowed designers to achieve good
driver efficiency. The PFC section has superior performance in terms of harmonic content
mitigation. High power factor (PF) and total harmonic distortion (THD) reduction are
obtained as required by international norms, especially concerning universal input voltage
operations. The TM PFC operation and high-efficiency performance of the half-bridge
topology provide very good overall circuit efficiency.
Film capacitors are one of the most popular types of discrete components. They generally
offer excellent electrical properties and are advantageous in high current and high
temperature conditions. For these reasons, film capacitors are used in LED SMPS
applications. In order to guarantee maintenance-free operation required by these types of
applications during the useful lifetime of the LED, electrolytic capacitors have been replaced
by film capacitors in the STEVAL-ILL038V1 board.
Other features, such as half-bridge overcurrent with frequency increase and PFC
overvoltage, allow designers to build a reliable, flexible solution with a reduced component
count.
Figure 1.
August 2011
STEVAL-ILL038V1 demonstration board
Doc ID 018857 Rev 1
1/25
www.st.com
Contents
AN3407
Contents
1
L6585DE combo IC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
2
Main characteristics and circuit description . . . . . . . . . . . . . . . . . . . . . 5
2.1
VCC section . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.2
Power factor corrector section . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.3
Resonant power section . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2.4
Output voltage feedback loop . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
3
Efficiency measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
4
Input current harmonics measurement . . . . . . . . . . . . . . . . . . . . . . . . . 11
5
Functional check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
5.1
PFC circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
5.2
Half-bridge resonant LLC circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
5.3
Converter startup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
6
Bill of material . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
7
EMI choke . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
8
PFC coil specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
9
Transformer specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
10
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
11
Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
2/25
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AN3407
List of figures
List of figures
Figure 1.
Figure 2.
Figure 3.
Figure 4.
Figure 5.
Figure 6.
Figure 7.
Figure 8.
Figure 9.
Figure 10.
Figure 11.
Figure 12.
Figure 13.
Figure 14.
Figure 15.
Figure 16.
Figure 17.
Figure 18.
Figure 19.
Figure 20.
Figure 21.
Figure 22.
Figure 23.
Figure 24.
Figure 25.
Figure 26.
Figure 27.
Figure 28.
Figure 29.
Figure 30.
STEVAL-ILL038V1 demonstration board . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Application example . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Multiplier . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Oscillator characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Half-bridge protection thresholds during run mode. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Electrical schematic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
STEVAL-ILL038V1 demonstration board: efficiency vs. load . . . . . . . . . . . . . . . . . . . . . . . 10
STEVAL-ILL038V1 demonstration board: full-load efficiency vs. VAC . . . . . . . . . . . . . . . . 10
STEVAL-ILL038V1 demonstration board: power factor vs. load . . . . . . . . . . . . . . . . . . . . 10
EN61000-3-2 Class-D standard - 185 VAC/50 Hz, THD=4.86%, PF=0.993 at full load . . . 11
EN61000-3-2 Class-D standard - 230 VAC/50 Hz, THD=5.98%, PF=0.980 at full load . . . 11
Input current waveforms - full load at 115 VAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Input current waveforms - full load at 230 VAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
PFC stage waveforms at 115 VAC - full load . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
PFC stage waveforms at 230 VAC - full load . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
PFC stage waveforms at 115 VAC - full load - detail . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
PFC stage waveforms at 230 VAC - full load - detail . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Primary side LLC waveforms at 115 VAC - full load . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Secondary side LLC waveforms at 230 VAC - full load . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
High-frequency ripple on output voltage at 115 VAC - 60 Hz - full load . . . . . . . . . . . . . . . 15
Low-frequency ripple on output voltage at 115 VAC - 60 Hz - full load . . . . . . . . . . . . . . . 15
Wake-up at 115 VAC - 60 Hz - full load . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Wake-up at 230 VAC - 60 Hz - full load . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
PCB: topside and through-hole components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
PCB: bottomside and SMD components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
PCB: topside placement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
PCB: bottomside placement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
EMI: OTC21V-4S vertical type EMI choke . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
PFC: QP2520V-vertical type for PFC choke. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Transformer: LP2920H - horizontal type for LLC transformer. . . . . . . . . . . . . . . . . . . . . . . 22
Doc ID 018857 Rev 1
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L6585DE combo IC
1
AN3407
L6585DE combo IC
The L6585DE embeds both a PFC converter and a half-bridge resonant in a single SO20
package.
●
Transition mode PFC converter with overvoltage and overcurrent protection
●
Half-bridge controller with high-voltage driver (600 Vdc) and integrated bootstrap diode
●
3% precise, fully programmable oscillator
●
Overcurrent protection
●
Hard-switching detection
Figure 2.
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Application example
Doc ID 018857 Rev 1
AN3407
2
Main characteristics and circuit description
Main characteristics and circuit description
The main features of the SMPS are listed here below:
2.1
●
Extended input mains range: 90 ~ 265 VAC - frequency 50/60 Hz
●
Output voltage: 48 V at 2.08 A
●
Long-life, electrolytic capacitors are not used
●
Mains harmonics: according to EN61000-3-2 Class-D
●
Efficiency at full load: better than 90%
●
Dimensions: 75 x 135 mm
VCC section
The L6585DE is supplied by applying voltage between the VCC pin and GND pin. An
undervoltage lockout (UVLO) prevents the IC from operating with supply voltages too low to
guarantee the correct behavior of the internal structures.
An internal voltage clamp limits the voltage to around 17 V and a delivery up to 20 mA. For
this reason it cannot be used directly as a clamp for the charge pump (current peaks usually
reach several hundreds of mA), but can be easily used during startup in order to charge the
VCC capacitor or during save mode in order to keep the IC alive, for example, connecting
VCC to input voltage through a resistor.
The L6585DE is supplied by the startup MOSFET Q4 and R40 charging the capacitor C25.
A charge pump connected to the auxiliary winding of the HB inductor T2 supplies the
controller via a small linear regulator represented by Q7. Once both stages have been
activated, the controllers are supplied also by the auxiliary winding of the resonant
transformer, assuring correct supply voltage during all load conditions. As the voltage on the
VCC pin reaches the turn-on threshold, the chip is enabled, and the half-bridge and the PFC
sections start at the same time.
2.2
Power factor corrector section
The PFC output voltage is controlled by means of a voltage-mode error amplifier and a
precise internal voltage reference. The PFC section achieves current mode control
operating in transition mode, offering a highly linear multiplier including a THD optimizer that
allows for an extremely low THD, even over a large range of input voltages and loading
conditions.
The controller is the L6585DE (U1), working in transition mode and integrating all functions
that are needed to perform the PFC. It delivers a stable 450 Vdc. It is a conventional boost
converter connected to the output of the rectifier bridge. It includes the coil T1, the PFC
transformer by YuJing, the diode D2 (STTH3L06U) and the PFC output capacitors C2, C3
and C4 by film type of 5 µF/800 V. The T1 provides also the information about the PFC coil
core demagnetization to pin#11 (ZCD) of the L6585DE. The T1 auxiliary winding is
connected to pin#11 (ZCD) of the L6585DE through the resistor R10. Its purpose is to
provide the information that T1 has demagnetized which is needed by the internal logic for
triggering a new switching cycle. The boost switch is represented by the power MOSFET
Q2. The T1 secondary winding (pins#8-6) and related circuitry are dedicated to power the
L6585DE during normal operation.
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Main characteristics and circuit description
AN3407
The divider R6, R9, R14 and R16 provides to the L6585DE multiplier the information of the
instantaneous mains voltage that is used to modulate the peak current of the boost. In
Figure 3 the characteristic curves of the multiplier are given. The resistors R1, R3, R7 with
R11 and C31 are dedicated to sense the output voltage and feed to the L6585DE the
feedback information necessary to maintain the output voltage regulated. The components
C7, R13 and C8 constitute the error amplifier compensation network necessary to keep the
required loop stability.
The resistors R2, R4, R5 with R8 are dedicated to detecting two different overvoltage
protections: dynamic overvoltage usually due to fast load transition, and static overvoltage
due to an excessive input voltage. The PFC boost peak current is sensed by resistors R23 in
series to the MOSFET source. The signal is fed into pin#12 (PFCS) of the L6585DE. The
protection is not latched, once the PFCCS falls below 1.7 V, the PFC driver restarts.
Figure 3.
2.3
Multiplier
Resonant power section
The resonant converter half-bridge topology works in ZVS. The resonant transformer T2,
manufactured by YuJing, uses the integrated magnetic approach. The leakage inductance is
used for resonant operation of the circuit. The T2 doesn't need an external coil for the
resonance. The T2 secondary winding configuration is the typical center tap, using a couple
of type D5 and D7 power Schottky rectifiers. The output capacitors are film type C15 and
C16 (4.7 µF/63 V). L2 and C17 filters have been added on the output, in order to filter the
high-frequency ripple.
The half-bridge driver oscillation is regulated by a current-controlled oscillator. It needs a
capacitor connected to pin#1 (OSC) of the L6585DE and uses the current flowing outside
pin#2 (RF) of the L6585DE as reference. Pin#2 (RF) of the L6585DE has a 2 V precise
voltage reference that lets the designer fix the run mode frequency simply by connecting a
resistor R17 between pin#2 (RF) of the L6585DE and GND. Each curve is related to a value
of the C13 capacitor and is depicted in Figure 4. Pin#3 (EOI) of the L6585DE is driven by
the internal logic in order to set the frequency during the startup.
Pin#4 (Tch) of the L6585DE is connected to the parallel of a resistor R18 and C11 and is
used to define the protection time. Pin#6 (EOL) of the L6585DE is the input of an internal
window comparator that can be triggered by a voltage variation due to a rectifying effect.
The reference of this comparator and the amplitude of the window can be set by connecting
a suitable resistor to pin#5 (EOLP) of the L6585DE. The reference of this comparator can be
set at a fixed voltage or at the same voltage as pin#7 (CTR) of the L6585DE.
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AN3407
Main characteristics and circuit description
Figure 4.
Oscillator characteristics
Pin #14 (HBCS) of the L6585DE is equipped with a current sensing and a dedicated
overcurrent management system. When the EOI voltage reaches 1.9 V, the IC enters run
mode and the switching frequency is set only by R17 (RRUN). In Figure 5 the protection
thresholds are shown. They are sensed by the circuit C18, R26, D8, D9, R27, and C19 and
are fed into the L6585DE pin#14 (HBCS).
Figure 5.
2.4
Half-bridge protection thresholds during run mode
Output voltage feedback loop
The output voltage is kept stable by means of a feedback loop implementing a typical circuit
using U3 (TS2431) modulating the current in the optocoupler diode. On the primary side,
R34 connecting pin#2 (RF) of the L6585DE to the optocoupler's phototransistor allows
modulating the L6585DE oscillator frequency, thus keeping the output voltage regulated.
R17 connects the same pin to ground and sets the minimum switching frequency.
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Main characteristics and circuit description
Electrical schematic
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Figure 6.
AN3407
!-V
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3
Efficiency measurements
Efficiency measurements
Table 1 shows the overall efficiency, measured at 115 VAC - 60 Hz. Table 2 shows the overall
efficiency, measured at 230 VAC - 50 Hz.
Table 1.
Efficiency at 115 VAC
115 VAC - 60 Hz
Load
Vout (V)
Iout (A)
Pout (W)
Pin (W)
PF
Eff (%)
25%
48.67
0.525
25.55
29.30
0.982
87.21
50%
48.67
1.050
51.10
55.87
0.996
91.47
75%
48.67
1.560
75.93
82.01
0.995
92.58
100%
48.67
2.086
101.53
109.28
0.991
92.90
Average eff.
Table 2.
91.04
Efficiency at 230 VAC
230 VAC - 50Hz
Load
Vout (V)
Iout (A)
Pout (W)
Pin (W)
PF
Eff (%)
25%
48.67
0.525
25.55
29.45
0.793
86.76
50%
48.67
1.048
51.01
55.59
0.924
91.76
75%
48.67
1.560
75.93
81.06
0.966
93.67
100%
48.67
2.083
101.38
107.46
0.980
94.34
Average eff.
91.63
The overall circuit efficiency is measured at different loads, powering the board at the two
nominal input mains voltages. The measures have been done after 30 minutes at load. The
high efficiency of the PFC working in transition mode and the very high efficiency of the
resonant stage working in ZVS provides for an overall efficiency better than 90%.
Figure 7 shows the efficiency at 25%, 50%, 75% and 100% load at 115 VAC and 230 VAC.
Figure 8 shows the efficiency at full load over the entire AC input voltage mains range.
Figure 9 shows the power factor (PF) versus load variations.
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Efficiency measurements
10/25
AN3407
Figure 7.
STEVAL-ILL038V1 demonstration board: efficiency vs. load
Figure 8.
STEVAL-ILL038V1 demonstration board: full-load efficiency vs. VAC
Figure 9.
STEVAL-ILL038V1 demonstration board: power factor vs. load
Doc ID 018857 Rev 1
AN3407
4
Input current harmonics measurement
Input current harmonics measurement
The internal THD optimizer increases the performance when the mains voltage reaches
zero which reduces crossover distortion and avoids introducing offset. One of the main
purposes of a PFC pre-conditioner is the correction of input current distortion, decreasing
the harmonic contents below the limits of the relevant regulations. The board has been
tested according to the European norm EN61000-3-2 Class-D, at full load and nominal input
voltage mains. Figure 10 and 11 show the measurement results.
Figure 10. EN61000-3-2 Class-D standard - 185 VAC/50 Hz, THD=4.86%, PF=0.993 at
full load
Figure 11. EN61000-3-2 Class-D standard - 230 VAC/50 Hz, THD=5.98%, PF=0.980 at
full load
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Input current harmonics measurement
AN3407
Figure 12 and 13 show the waveforms of the input current and voltage at 115 VAC and 230
VAC during full load.
Figure 12. Input current waveforms - full load
at 115 VAC
CH2: Vac-in
12/25
CH4: Iac-in
Figure 13. Input current waveforms - full load
at 230 VAC
CH2: Vac-in
Doc ID 018857 Rev 1
CH3: Iac-in
AN3407
Functional check
5
Functional check
5.1
PFC circuit
The waveforms measured in the PFC stage have been captured during full load operation at
nominal 115 VAC and 230 VAC in Figure 14 and 15. It can be seen in both figures that the
envelope of the waveform of pin#12 (PFCS) is in phase with that of pin#8 (MULT) and has
same sinusoidal shape, demonstrating the proper functionality of the PFC stage. It is also
possible to measure the peak-to-peak value of the voltage ripple superimposed on the PFC
output voltage due to the low value of the PFC output capacitors. The details of the
waveforms at switching frequency are measured in Figure 16 and 17.
Figure 14. PFC stage waveforms at 115 VAC full load
CH1: MULT
CH2: PFCS
CH4: Vout_PFC
Figure 15. PFC stage waveforms at 230 VAC full load
CH1: MULT
CH2: PFCS
CH4: Vout_PFC
Figure 16. PFC stage waveforms at 115 VAC full load - detail
Figure 17. PFC stage waveforms at 230 VAC full load - detail
CH1: MULT CH3: Vdrain_Q2
CH1: MULT
CH3: Vout_PFC
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CH3: Vdrain_Q2 CH4: Vout_PFC
13/25
Functional check
5.2
AN3407
Half-bridge resonant LLC circuit
The waveforms are measured in the resonant stage ZVS operation in Figure 18. Both
MOSFETs are turned on when resonant current is flowing through their body diodes and
drain-source voltage is almost zero, thus achieving good efficiency. The switching frequency
has been chosen around 94 kHz.
Figure 18 shows waveforms during steady-state operation of the circuit at full load. A slight
asymmetry of operating modes by each half portion of the sine wave is visible: one halfcycle is working at resonant frequency while the other half is working above the resonant
frequency. This is due to a small difference between each half’s secondary leakage
inductance of the transformer reflected to the primary side, providing two slightly different
resonant frequencies. This phenomenon is typically due to a different coupling of the
transformer’s secondary windings and in this case it is not an issue.
Figure 19 demonstrates that during one half-cycle the circuit is working below the resonant
frequency, while during the following half-cycle it is working at resonance frequency.
Waveforms relevant to the secondary side are shown: the rectifier’s reverse voltage is
measured by Ch3 and Ch4 on the right of the picture. It is a bit higher than the theoretical
value that would be 2 (VOUT+VF), hence about 100 V.
Figure 18. Primary side LLC waveforms at
115 VAC - full load
CH1: VCC
14/25
CH3: Res. Tank current
CH4: HB
Figure 19. Secondary side LLC waveforms at
230 VAC - full load
CH1: Vout
Doc ID 018857 Rev 1
CH3: V_D7
CH4: V_D5
AN3407
Functional check
The ripple and noise on the output voltage is shown on CH1. Figure 20 shows the waveform
during the high-frequency ripple of the circuit at full load. The peak-to-peak value is high but
it doesn't affect the application, in fact the converters regulating the current flowing in each
LED strip can reject the ripple. Figure 21 shows the waveform during the low-frequency
ripple of the circuit at full load.
Figure 20. High-frequency ripple on output
Figure 21. Low-frequency ripple on output
voltage at 115 VAC - 60 Hz - full load
voltage at 115 VAC - 60 Hz - full load
CH1: Vout
5.3
CH1: Vout
Converter startup
The converter startup is captured in Figure 22 and 23. The converter begins operation
around 80 ms at 115 VAC and 230 VAC. This is the time needed to charge the VCC to turnon voltage. The L6585DE starts switching and the PFC and HB output voltage starts
increasing.
Figure 22. Wake-up at 115 VAC - 60 Hz - full
load
CH1: VCC
CH3: VOUT
CH4: HB
Figure 23. Wake-up at 230 VAC - 60 Hz - full
load
CH1: VCC
Doc ID 018857 Rev 1
CH3: VOUT
CH4: HB
15/25
Bill of material
AN3407
6
Bill of material
Table 3.
STEVAL-ILL038V1 demonstration board: bill of material
Reference
Part / value
BD1
GBU8J_DIP
C1,C5,C9
470nF_DIP
305 VAC
EPCOS
C2,C3,C4
5uF/800 V_DIP
800 V
EPCOS
C6,C12
10 nF
X7R
50 V
C7,C11
2.2 µF
X7R
50 V
C8
0.33 µF
X7R
50 V
C10
470 nF
X7R
50 V
C13,C30
1 nF
X7R
50 V
C14
0.1 µF_1206
X7R
50 V
C15,C16
4.7 µF 63 V_DIP
C17
100 nF_1206
X7R
100 V
C18
220 pF_1206
X7R
1000 V
C19
330 nF
X7R
50 V
C20
15 nF_DIP
C21
2.2 nF_DIP
C22,C31
220 nF
X7R
50 V
C23
4.7 µF
X7R
25 V
C25
47 µF_CaseD
C26
0.47 µF_1206
X7R
50 V
C27
2.2 µF_1206
X7R
50 V
C28
0.22 µF
X7R
50 V
C29
15 nF
X7R
50 V
D1
1N4007_DIP
VISHAY
D2
STTH3L06U_SMB
STMicroelectronics
D3,D4,D6,D8,D9,
D10,D11,D12
1N4148
CHENMKO
D5,D7
STPS10150CG
STMicroelectronics
F1
4 A_DIP
Littlefuse
J1
CN1
PHOENIX CONTACT
J2
CON2
PHOENIX CONTACT
L1
QTC21_DIP
YU JING
L2
3.3 µH_DIP
MAGI
16/25
Tolerance %
Voltage
Manufacturer
VISHAY
63 V
1000 V
EPCOS
AVX
EPCOS
Murata
20 V
Doc ID 018857 Rev 1
SANYO
AN3407
Bill of material
Table 3.
STEVAL-ILL038V1 demonstration board: bill of material (continued)
Reference
Part / value
Q1,Q3
Tolerance %
Voltage
Manufacturer
STF8NM60N_DIP
600 V
STMicroelectronics
Q2
STF21NM60N_DIP
600 V
STMicroelectronics
Q4
STQ1HNK60R_DIP
STMicroelectronics
Q5,Q6,Q7
BC847
CHENMKO
RV1
VARISTOR
R1,R3
1 MΩ_1206
1%
R2
1.3 MΩ_1206
1%
R4
1.1 MΩ_1206
1%
R5
150 kΩ_1206
1%
R6,R9
2 MΩ_1206
1%
R7
1.5 MΩ_1206
1%
R8
18 kΩ
1%
R10
56 kΩ_1206
1%
R11
19.6 kΩ
1%
R13
51 kΩ
1%
R14
390 kΩ_1206
1%
R15,R32
120 kΩ
1%
R16,R17,R36
27 kΩ
1%
R18
270 kΩ
1%
R19
680 kΩ
1%
R20,R21,R24
22 Ω
5%
R23
0.15_DIP
1%
R25
110 kΩ_1206
1%
R26
110_1206
1%
R27
100 Ω
1%
R28
3 MΩ_1206
1%
R29
1.8 MΩ_1206
1%
R30
220 kΩ
1%
R31,R37
4.7 kΩ
5%
R33
1_1206
5%
R34
22 kΩ
1%
R35
620 Ω
1%
R38
49.9 kΩ
1%
R39
2.2 kΩ
1%
R40
12 kΩ_1206
1%
300 VAC
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Bill of material
Table 3.
AN3407
STEVAL-ILL038V1 demonstration board: bill of material (continued)
Reference
Part / value
Tolerance %
Voltage
R41
15 kΩ
1%
R44
2.7 kΩ
1%
T1
QP2520_DIP
YU JING
T2
LP2920_DIP
YU JING
U1
L6585DE
STMicroelectronics
U2
SFH617A
VISHAY
U3
TS2431
STMicroelectronics
ZD1
24 V
CHENMKO
ZD2
12 V
CHENMKO
ZD3
15 V
CHENMKO
Figure 24. PCB: topside and through-hole components
Figure 25. PCB: bottomside and SMD components
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Doc ID 018857 Rev 1
Manufacturer
AN3407
Bill of material
Figure 26. PCB: topside placement
Figure 27. PCB: bottomside placement
Doc ID 018857 Rev 1
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EMI choke
7
AN3407
EMI choke
Figure 28. EMI: OTC21V-4S vertical type EMI choke
MYLAR FILM
22.0 MAX
22.0 MAX
26.0 MAX
2
14±0.5
3
3.5±0.3
1
2
15.0±0.5
AM09845v1
Table 4.
Transformer specifications
Core spec-OTC21
Ae
26.1 mm2
Le
55.2 mm
Wiring spec. for resonant transformer
Note:
No.
Start
Finish
Wire
L1
1
4
L2
2
3
Winding
Turns
Inductance
DCR (mΩ)
0.55 Φ*
48
11.0 µH min
200 max.
0.55 Φ*
48
96 µH min
200 max.
Class B insulation system: SBI4.2
Hi-pot test: 1.5 kV, N1 to N2, 1.5 kV, N1 to core, 1.5 kV, N2 to core
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8
PFC coil specifications
PFC coil specifications
Figure 29. PFC: QP2520V-vertical type for PFC choke
!-V
Table 5.
Transformer specifications
Core spec-QP2520
Ae
2
118.0 mm
Le
46 mm
Wiring spec. for resonant transformer
Note:
No.
Start
Finish
Wire
Winding
Turns
Inductance
DCR (mΩ)
L1
1.2
3.4
0.1Φ 35c*
1p(Litz)
Primary
62±0.5
580 µH ±10%
280 max.
L2
7
6
0.3 Φ* 1c
AUX
6±0.5
Class B insulation system: SBI4.2
with standing voltage: 1.0 kV/3 sec/AC/5 mA, primary to secondary, 0.5 kV/1 sec/AC/3 mA,
primary to core, 0.5 kV/1 sec/AC/3 mA, secondary to core
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Transformer specifications
9
AN3407
Transformer specifications
Figure 30. Transformer: LP2920H - horizontal type for LLC transformer
-!8
-!8
0.
9*$#
-!8
›
Œ› ›
›
!-V
Table 6.
Transformer specifications
Core spec-LP2920
Ae
2
112.0 mm
Le
79.6 mm
Wiring spec. for resonant transformer
Note:
No.
Start
Finish
Wire
Winding
Turns
Inductance
L1
1
3
0.1Φ 30c*
1p(Litz)
Primary
47±0.5
770 µH ±10%
L2
5
6
0.28 Φ* 1c
(TEX-E)
AUX
3±0.5
L3
9
8
0.1 Φ* 60C*
1p (Litz)
Second
9±0.5
L4
11
10
0.1 Φ* 60c*
1p (Litz)
Second
9±0.5
Lk
1
3
0.1 Φ* 30c*
1p (Litz)
Primary
47±0.5
170 µH ±10%
DCR (mΩ)
Sec.short
Class B insulation system: SBI4.2
with standing voltage: 3.0 kV/1 sec/AC/5 mA, primary to secondary, 2.5 kV/1 sec/AC/3 mA,
primary to core, 1.0 kV/1 sec/AC/3 mA, secondary to core
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Doc ID 018857 Rev 1
AN3407
10
References
References
1.
L6585DE datasheet, STMicroelectronics
2.
L6562A datasheet, STMicroelectronics
3.
L6599 datasheet, STMicroelectronics
4.
Application notes: AN2870, AN3106, STMicroelectronics
Doc ID 018857 Rev 1
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Revision history
11
AN3407
Revision history
Table 7.
24/25
Document revision history
Date
Revision
30-Aug-2011
1
Changes
Initial release.
Doc ID 018857 Rev 1
AN3407
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