Is Now Part of
To learn more about ON Semiconductor, please visit our website at
www.onsemi.com
Please note: As part of the Fairchild Semiconductor integration, some of the Fairchild orderable part numbers
will need to change in order to meet ON Semiconductor’s system requirements. Since the ON Semiconductor
product management systems do not have the ability to manage part nomenclature that utilizes an underscore
(_), the underscore (_) in the Fairchild part numbers will be changed to a dash (-). This document may contain
device numbers with an underscore (_). Please check the ON Semiconductor website to verify the updated
device numbers. The most current and up-to-date ordering information can be found at www.onsemi.com. Please
email any questions regarding the system integration to Fairchild_questions@onsemi.com.
ON Semiconductor and the ON Semiconductor logo are trademarks of Semiconductor Components Industries, LLC dba ON Semiconductor or its subsidiaries in the United States and/or other countries. ON Semiconductor owns the rights to a number
of patents, trademarks, copyrights, trade secrets, and other intellectual property. A listing of ON Semiconductor’s product/patent coverage may be accessed at www.onsemi.com/site/pdf/Patent-Marking.pdf. ON Semiconductor reserves the right
to make changes without further notice to any products herein. ON Semiconductor makes no warranty, representation or guarantee regarding the suitability of its products for any particular purpose, nor does ON Semiconductor assume any liability
arising out of the application or use of any product or circuit, and specifically disclaims any and all liability, including without limitation special, consequential or incidental damages. Buyer is responsible for its products and applications using ON
Semiconductor products, including compliance with all laws, regulations and safety requirements or standards, regardless of any support or applications information provided by ON Semiconductor. “Typical” parameters which may be provided in ON
Semiconductor data sheets and/or specifications can and do vary in different applications and actual performance may vary over time. All operating parameters, including “Typicals” must be validated for each customer application by customer’s
technical experts. ON Semiconductor does not convey any license under its patent rights nor the rights of others. ON Semiconductor products are not designed, intended, or authorized for use as a critical component in life support systems or any FDA
Class 3 medical devices or medical devices with a same or similar classification in a foreign jurisdiction or any devices intended for implantation in the human body. Should Buyer purchase or use ON Semiconductor products for any such unintended
or unauthorized application, Buyer shall indemnify and hold ON Semiconductor and its officers, employees, subsidiaries, affiliates, and distributors harmless against all claims, costs, damages, and expenses, and reasonable attorney fees arising out
of, directly or indirectly, any claim of personal injury or death associated with such unintended or unauthorized use, even if such claim alleges that ON Semiconductor was negligent regarding the design or manufacture of the part. ON Semiconductor
is an Equal Opportunity/Affirmative Action Employer. This literature is subject to all applicable copyright laws and is not for resale in any manner.
FSFR2100 — Fairchild Power Switch (FPS™)
for Half-Bridge Resonant Converters
Features
Description
Variable Frequency Control with 50% Duty Cycle
for Half-bridge Resonant Converter Topology
High Efficiency through Zero Voltage Switching (ZVS)
Fixed Dead Time (350 ns) Optimized for MOSFETs
Remote On/Off Control Using Control Pin
The FSFR2100 is a highly integrated power switch
designed for high-efficiency half-bridge resonant
converters. Offering everything necessary to build a
reliable and robust resonant converter, the FSFR2100
simplifies designs and improves productivity, while
improving performance. The FSFR2100 combines power
MOSFETs with fast-recovery type body diodes, a highside gate-drive circuit, an accurate current controlled
oscillator, frequency limit circuit, soft-start, and built-in
protection functions. The high-side gate-drive circuit has
a common-mode noise cancellation capability, which
guarantees stable operation with excellent noise
immunity. The fast-recovery body diode of the MOSFETs
improves reliability against abnormal operation
conditions, while minimizing the effect of the reverse
recovery. Using the zero-voltage-switching (ZVS)
technique dramatically reduces the switching losses and
efficiency is significantly improved. The ZVS also
reduces the switching noise noticeably, which allows a
small-sized Electromagnetic Interference (EMI) filter.
Internal SuperFET™s with Fast-Recovery Type
Body Diode (trr=120 ns)
Up to 300kHz Operating Frequency
Pulse Skipping for Frequency Limit (Programmable)
at Light-Load Condition
Protection Functions: Over-Voltage Protection
(OVP), Over-Load Protection (OLP), Over-Current
Protection (OCP), Abnormal Over-Current Protection
(AOCP), Internal Thermal Shutdown (TSD)
Applications
The FSFR2100 can be applied to various resonant
converter topologies, such as: series resonant, parallel
resonant, and LLC resonant converters.
PDP and LCD TVs
Desktop PCs and Servers
Adapters
Related Resources
Telecom Power Supplies
Audio Power Supplies
AN-4151 — Half-Bridge LLC Resonant Converter
Design Using FSFR2100 Fairchild Power Switch
(FPS™)
Evaluation Board: FEBFSFR2100_D015v1
Ordering Information
Part
Number
Package
Operating
Junction
Temperature
RDS(ON_MAX)
Maximum Output Power
without Heatsink
(VIN=350~400 V)(1,2)
Maximum Output
Power with Heatsink
(VIN=350~400 V)(1,2)
FSFR2100
9-SIP
-40 to +130°C
0.38
200 W
450 W
Notes:
1. The junction temperature can limit the maximum output power.
2. Maximum practical continuous power in an open-frame design at 50C ambient.
© 2010 Fairchild Semiconductor Corporation
FSFR2100 • Rev.1.1.0
www.fairchildsemi.com
FSFR2100 — Fairchild Power Switch (FPS™) for Half-Bridge Resonant Converters
February 2013
FSFR2100 — Fairchild Power Switch (FPS™) for Half-Bridge Resonant Converters
Application Circuit Diagram
Figure 1. Typical Application Circuit (LLC Resonant Half-Bridge Converter)
Block Diagram
1.5 s
Figure 2. Internal Block Diagram
© 2010 Fairchild Semiconductor Corporation
FSFR2100 • Rev.1.1.0
www.fairchildsemi.com
2
Figure 3. Package Diagram
Pin Definitions
Pin #
Name
1
VDL
Description
This is the drain of the high-side MOSFET, typically connected to the input DC link voltage.
2
CON
This pin is for enable/disable and protection. When the voltage of this pin is above 0.6 V, the
IC operation is enabled. When the voltage of this pin drops below 0.4 V, gate drive signals
for both MOSFETs are disabled. When the voltage of this pin increases above 5 V,
protection is triggered.
3
RT
This pin programs the switching frequency. Typically, an opto-coupler is connected to control
the switching frequency for the output voltage regulation.
4
CS
This pin senses the current flowing through the low-side MOSFET. Typically, negative
voltage is applied on this pin.
5
SG
This pin is the control ground.
6
PG
This pin is the power ground. This pin is connected to the source of the low-side MOSFET.
7
LVCC
8
NC
9
HVCC
This is the supply voltage of the high-side gate-drive circuit IC.
10
VCTR
This is the drain of the low-side MOSFET. Typically, a transformer is connected to this pin.
This pin is the supply voltage of the control IC.
No connection.
© 2010 Fairchild Semiconductor Corporation
FSFR2100 • Rev.1.1.0
www.fairchildsemi.com
3
FSFR2100 — Fairchild Power Switch (FPS™) for Half-Bridge Resonant Converters
Pin Configuration
Stresses exceeding the absolute maximum ratings may damage the device. The device may not function or be
operable above the recommended operating conditions and stressing the parts to these levels is not recommended. In
addition, extended exposure to stresses above the recommended operating conditions may affect device reliability. The
absolute maximum ratings are stress ratings only. TA=25C unless otherwise specified.
Symbol
Parameter
Min.
VDS
Maximum Drain-to-Source Voltage (VDL-VCTR and VCTR-PG)
600
LVCC
Low-Side Supply Voltage
-0.3
HVCC to VCTR High-Side VCC Pin to Low-side Drain Voltage
Max.
Unit
V
25.0
V
-0.3
25.0
V
HVCC
High-Side Floating Supply Voltage
-0.3
625.0
V
VCON
Control Pin Input Voltage
-0.3
LVCC
V
VCS
Current Sense (CS) Pin Input Voltage
-5.0
1.0
V
VRT
RT Pin Input Voltage
-0.3
5.0
V
50
V/ns
12
W
dVCTR/dt
PD
TJ
TSTG
Allowable Low-Side MOSFET Drain Voltage Slew Rate
(3)
Total Power Dissipation
Maximum Junction Temperature(4)
+150
Recommended Operating Junction Temperature(4)
-40
+130
Storage Temperature Range
-55
+150
C
C
MOSFET Section
VDGR
Drain Gate Voltage (RGS=1 M)
VGS
Gate Source (GND) Voltage
600
V
(5)
IDM
Drain Current Pulsed
ID
Continuous Drain Current
±30
V
33
A
TC=25C
11
TC=100C
7
A
Package Section
Torque
Recommended Screw Torque
5~7
kgf·cm
Notes:
3. Per MOSFET when both MOSFETs are conducting.
4. The maximum value of the recommended operating junction temperature is limited by thermal shutdown.
5. Pulse width is limited by maximum junction temperature.
Thermal Impedance
TA=25C unless otherwise specified.
Symbol
Parameter
θJC
Junction-to-Case Center Thermal Impedance (Both MOSFETs Conducting)
θJA
Junction-to-Ambient Thermal Impedance
© 2010 Fairchild Semiconductor Corporation
FSFR2100 • Rev.1.1.0
Value
Unit
10.44
ºC/W
80
ºC/W
www.fairchildsemi.com
4
FSFR2100 — Fairchild Power Switch (FPS™) for Half-Bridge Resonant Converters
Absolute Maximum Ratings
TA=25C unless otherwise specified.
Symbol
Parameter
Test Conditions
Min.
Typ.
Max.
Unit
MOSFET Section
BVDSS
Drain-to-Source Breakdown Voltage
RDS(ON)
On-State Resistance
trr
CISS
COSS
ID=200 μA, TA=25C
(6)
Body Diode Reverse Recovery Time
(6)
Input Capacitance
Output Capacitance
(6)
600
V
ID=200 μA, TA=125C
650
VGS=10 V, ID=5.5 A
0.32
VGS=0 V, IDiode=11.0 A
120
ns
VDS=25V, VGS=0 V,
f=1.0 MHz
1148
pF
671
pF
0.38
Supply Section
ILK
Offset Supply Leakage Current
H-VCC=VCTR=600 V/500 V
50
μA
IQHVCC
Quiescent HVCC Supply Current
(HVCCUV+) - 0.1 V
50
120
μA
IQLVCC
Quiescent LVCC Supply Current
(LVCCUV+) - 0.1 V
100
200
μA
IOHVCC
Operating HVCC Supply Current
(RMS Value)
fOSC=100 KHz, VCON > 0.6 V
6
9
mA
No Switching, VCON < 0.4 V
100
200
μA
IOLVCC
Operating LVCC Supply Current
(RMS Value)
fOSC=100KHz, VCON > 0.6 V
7
11
mA
No Switching, VCON < 0.4 V
2
4
mA
UVLO Section
LVCCUV+
LVCC Supply Under-Voltage Positive-Going Threshold (LVCC Start)
13.0
14.5
16.0
V
LVCCUV-
LVCC Supply Under-Voltage Negative-Going Threshold (LVCC Stop)
10.2
11.3
12.4
V
LVCCUVH
LVCC Supply Under-Voltage Hysteresis
HVCCUV+
HVCC Supply Under-Voltage Positive-Going Threshold (HVCC Start)
8.2
9.2
10.2
V
HVCCUV-
HVCC Supply Under-Voltage Negative-Going Threshold (HVCC Stop)
7.8
8.7
9.6
V
HVCCUVH
HVCC Supply Under-Voltage Hysteresis
3.2
V
0.5
V
Oscillator & Feedback Section
VCONDIS
Control Pin Disable Threshold Voltage
0.36
0.40
0.44
V
VCONEN
Control Pin Enable Threshold Voltage
0.54
0.60
0.66
V
VRT
V-I Converter Threshold Voltage
1.5
2.0
2.5
V
fOSC
Output Oscillation Frequency
94
100
106
KHz
DC
Output Duty Cycle
48
50
52
%
fSS
Internal Soft-Start Initial Frequency
tSS
Internal Soft-Start Time
RT=5.2 K
140
fSS=fOSC+40 kHz, RT=5.2 K
2
3
KHz
4
ms
Continued on the following page…
© 2010 Fairchild Semiconductor Corporation
FSFR2100 • Rev.1.1.0
www.fairchildsemi.com
5
FSFR2100 — Fairchild Power Switch (FPS™) for Half-Bridge Resonant Converters
Electrical Characteristics
TA=25C unless otherwise specified.
Symbol
Parameter
Test Conditions
Min.
Typ.
Max.
Unit
Protection Section
IOLP
OLP Delay Current
VCON=4 V
3.6
4.8
6.0
μA
VOLP
OLP Protection Voltage
VCON > 3.5 V
4.5
5.0
5.5
V
VOVP
LVCC Over-Voltage Protection
L-VCC > 21 V
21
23
25
V
VAOCP
AOCP Threshold Voltage
V/t=-0.1 V/µs
-1.0
-0.9
-0.8
V
(6)
tBAO
AOCP Blanking Time
VCS < VAOCP; V/t=-0.1 V/µs
VOCP
OCP Threshold Voltage
V/t=-1 V/µs
(6)
tBO
OCP Blanking Time
VCS < VOCP; V/t=-1 V/µs
tDA
Delay Time (Low Side) Detecting from
(6)
VAOCP to Switch Off
V/t=-1 V/µs
TSD
Thermal Shutdown Temperature(6)
ISU
Protection Latch Sustain LVCC Supply
Current
VPRSET
50
ns
-0.64
-0.58
-0.52
V
1.0
1.5
2.0
μs
250
400
ns
130
150
C
100
150
μA
110
LVCC=7.5 V
Protection Latch Reset LVCC Supply
Voltage
5
V
Dead-Time Control Section
DT
Dead Time(7)
350
ns
Notes:
6. This parameter, although guaranteed, is not tested in production.
7. These parameters, although guaranteed, are tested only in EDS (wafer test) process.
© 2010 Fairchild Semiconductor Corporation
FSFR2100 • Rev.1.1.0
www.fairchildsemi.com
6
FSFR2100 — Fairchild Power Switch (FPS™) for Half-Bridge Resonant Converters
Electrical Characteristics (Continued)
1.1
1.1
1.05
1.05
Normalized at 25OC
Normalized at 25OC
These characteristic graphs are normalized at TA=25°C.
1
0.95
1
0.95
0.9
0.9
-50
-25
0
25
50
75
-50
100
-25
0
Temp (OC)
50
75
100
Figure 5. Switching Frequency vs. Temperature
1.1
1.1
1.05
1.05
Normalized at 25OC
Normalized at 25OC
Figure 4. Low-Side MOSFET Duty Cycle
vs. Temperature
1
0.95
0.9
1
0.95
0.9
-50
-25
0
25
50
75
100
-50
-25
0
25
50
75
100
Temp (OC)
Temp (OC)
Figure 6. High-Side VCC (HVCC) Start
vs. Temperature
Figure 7. High-Side VCC (HVCC) Stop
vs. Temperature
1.1
1.1
1.05
1.05
Normalized at 25OC
Normalized at 25OC
25
Temp (OC)
1
0.95
1
0.95
0.9
0.9
-50
-25
0
25
Temp
50
75
-50
100
Figure 8. Low-Side VCC (LVCC) Start
vs. Temperature
© 2010 Fairchild Semiconductor Corporation
FSFR2100 • Rev.1.1.0
-25
0
25
50
75
100
Temp (OC)
(OC)
Figure 9. Low-Side VCC (LVCC) Stop
vs. Temperature
www.fairchildsemi.com
7
FSFR2100 — Fairchild Power Switch (FPS™) for Half-Bridge Resonant Converters
Typical Performance Characteristics
1.1
1.1
1.05
1.05
Normalized at 25OC
Normalized at 25OC
These characteristic graphs are normalized at TA=25°C.
1
0.95
-50
-25
0
25
50
75
-50
100
-25
0
25
50
75
100
Temp (OC)
Temp (OC)
Figure 10. OLP Delay Current
vs. Temperature
Figure 11. OLP Protection Voltage
vs. Temperature
1.1
1.1
1.05
1.05
Normalized at 25OC
Normalized at 25OC
0.95
0.9
0.9
1
0.95
1
0.95
0.9
0.9
-50
-25
0
25
50
75
-50
100
-25
0
25
50
75
100
Temp (OC)
Temp (OC)
Figure 12. LVCC OVP Voltage vs. Temperature
Figure 13. RT Voltage vs. Temperature
1.1
1.1
1.05
1.05
Normalized at 25OC
Normalized at 25OC
1
1
0.95
1
0.95
0.9
0.9
-50
-25
0
25
Temp
50
75
-50
100
Figure 14. CON Pin Enable Voltage
vs. Temperature
© 2010 Fairchild Semiconductor Corporation
FSFR2100 • Rev.1.1.0
-25
0
25
50
75
100
Temp (OC)
(OC)
Figure 15. OCP Voltage vs. Temperature
www.fairchildsemi.com
8
FSFR2100 — Fairchild Power Switch (FPS™) for Half-Bridge Resonant Converters
Typical Performance Characteristics (Continued)
Gain
1. Basic Operation
1.8
FSFR2100 is designed to drive high-side and low-side
MOSFETs complementarily with 50% duty cycle. A fixed
dead time of 350 ns is introduced between consecutive
transitions, as shown in Figure 16.
f min
f normal
f max
f ISS
1.6
1.4
1.2
1.0
Soft-start
0.8
0.6
60
70
80
90
100
110
120
130
140
150
freq (kHz)
Figure 16. MOSFETs Gate Drive Signal
Figure 18. Resonant Converter Typical Gain Curve
2. Internal Oscillator
LVCC
FSFR2100 employs a current-controlled oscillator, as
shown in Figure 17. Internally, the voltage of RT pin is
regulated at 2 V and the charging/discharging current for
the oscillator capacitor, CT, is obtained by copying the
current flowing out of RT pin (ICTC) using a current mirror.
Therefore, the switching frequency increases as ICTC
increases.
VDL
RT
Rmax
Rmi
Rss
Css CON
Control
IC
SG
PG
Figure 19. Frequency Control Circuit
The minimum switching frequency is determined as:
f min
Figure 17. Current Controlled Oscillator
(1)
Assuming the saturation voltage of opto-coupler
transistor is 0.2 V, the maximum switching frequency is
determined as:
3. Frequency Setting
Figure 18 shows a typical voltage gain curve of a
resonant converter, where the gain is inversely
proportional to the switching frequency in the ZVS region.
The output voltage can be regulated by modulating the
switching frequency. Figure 19 shows the typical circuit
configuration for RT pin, where the opto-coupler transistor
is connected to the RT pin to modulate the switching
frequency.
© 2010 Fairchild Semiconductor Corporation
FSFR2100 • Rev.1.1.0
5.2k
100(kHz )
Rmin
f max (
5.2k 4.68k
) 100(kHz )
Rmin
Rmax
(2)
To prevent excessive inrush current and overshoot of
output voltage during startup, increase the voltage gain
of the resonant converter progressively. Since the
voltage gain of the resonant converter is inversely
proportional to the switching frequency, the soft-start is
implemented by sweeping down the switching frequency
from an initial high frequency (f I S S ) until the output
voltage is established. The soft-start circuit is made by
connecting R-C series network on the RT pin, as shown
in Figure 19. FSFR2100 also has an internal soft-start for
www.fairchildsemi.com
9
FSFR2100 — Fairchild Power Switch (FPS™) for Half-Bridge Resonant Converters
Functional Description
f ISS (
5.2k 5.2k
) 100 40 ( kHz )
Rmin
RSS
(3)
It is typical to set the initial frequency of soft-start two ~
three times the resonant frequency (fO) of the resonant
network.
The soft-start time is three to four times of the RC time
constant. The RC time constant is as follows:
TSS RSS C SS
(4)
Figure 22. Control Pin Configuration for Pulse
Skipping
fs
f ISS
Remote On / Off: When an auxiliary power supply is
used for standby, the main power stage using FSFR2100
can be shut down by pulling down the control pin voltage,
as shown in Figure 23. R1 and C1 are used to ensure
soft-start when switching resumes.
40kHz
Control loop
take over
time
Figure 20. Frequency Sweeping of Soft-start
4. Control Pin
The FSFR2100 has a control pin for protection, cycle
skipping, and remote on/off. Figure 21 shows the internal
block diagram for control pin.
Figure 23. Remote On / Off Circuit
Figure 21. Internal Block of Control Pin
Protection: When the control pin voltage exceeds 5V,
protection is triggered. Detailed applications are
described in the protection section.
Pulse Skipping: FSFR2100 stops switching when the
control pin voltage drops below 0.4 V and resumes
switching when the control pin voltage rises above 0.6 V.
To use pulse-skipping, the control pin should be
connected to the opto-coupler collector pin. The
frequency that causes pulse skipping is given as:
SKIP
5. 2 k
4.16 k
R min
R max
© 2010 Fairchild Semiconductor Corporation
FSFR2100 • Rev.1.1.0
x100kHz
(5)
www.fairchildsemi.com
10
FSFR2100 — Fairchild Power Switch (FPS™) for Half-Bridge Resonant Converters
3 ms to reduce the current overshoot during the initial
cycles, which adds 40 kHz to the initial frequency of the
external soft-start circuit, as shown in Figure 20. The
initial frequency of the soft-start is given as:
Current Sensing Using Resistor: FSFR2100 senses
drain current as a negative voltage, as shown in Figure
24 and Figure 25. Half-wave sensing allows low power
dissipation in the sensing resistor, while full-wave
sensing has less switching noise in the sensing signal.
Cr
Np
Ns
Ns
Control
IC
VCS
Ids
CS
SG
PG
Rsense
VCS
Ids
Figure 24. Half-Wave Sensing
Ids
Vsense pk
CB
VCr p p Csense CB
Vsense pk
VCON
2
VCS
Tdelay Rd Cd
Cr
Control
IC
VCS
Np
CS
PG
SG
Rsense
Figure 26. Current Sensing Using Resonant
Capacitor Voltage
Ns
6. Protection Circuits
Ns
The FSFR2100 has several self-protective functions,
such as Overload Protection (OLP), Over-Current
Protection (OCP), Abnormal Over-Current Protection
(AOCP), Over-Voltage Protection (OVP), and Thermal
Shutdown (TSD). OLP, OCP, and OVP are auto-restart
mode protections; while AOCP and TSD are latch-mode
protections, as shown in Figure 27.
Ids
Figure 25. Full-Wave Sensing
Current Sensing Using Resonant Capacitor Voltage:
For high-power applications, current sensing using a
resistor may not be available due to the severe power
dissipation in the resistor. In that case, indirect current
sensing using the resonant capacitor voltage can be a
good alternative because the amplitude of the resonant
p-p
capacitor voltage (Vcr ) is proportional to the resonant
current in the primary side (Ipp-p) as:
VCr p p
I p p p
2 f sCr
6.1
Auto-restart Mode Protection: Once a fault
condition is detected, switching is terminated and the
MOSFETs remain off. When LVCC falls to the LVCC stop
voltage of 11.3 V, the protection is reset. The FPS
resumes normal operation when LVCC reaches the start
voltage of 14.5 V.
(6)
To minimize power dissipation, a capacitive voltage
divider is generally used for capacitor voltage sensing, as
shown in Figure 26.
© 2010 Fairchild Semiconductor Corporation
FSFR2100 • Rev.1.1.0
www.fairchildsemi.com
11
FSFR2100 — Fairchild Power Switch (FPS™) for Half-Bridge Resonant Converters
5. Current Sensing
6.7
Thermal Shutdown (TSD): The MOSFETs and
the control IC in one package makes it easy for the
control IC to detect the abnormal over-temperature of the
MOSFETs. If the temperature exceeds approximately
130C, the thermal shutdown triggers.
7.
Figure 27. Protection Blocks
6.3
Over-Current Protection (OCP): When the
sensing pin voltage drops below -0.58 V, OCP is
triggered and the MOSFETs remain off. This protection
has a shutdown time delay of 1.5 µs to prevent
premature shutdown during startup.
6.4
Abnormal Over-Current Protection (AOCP): If
the secondary rectifier diodes are shorted, large current
with extremely high di/dt can flow through the MOSFET
before OCP or OLP is triggered. AOCP is triggered
without shutdown delay when the sensing pin voltage
drops below -0.9V. This protection is latch mode and
reset when LVCC is pulled down below 5 V.
6.5
Overload Protection (OLP): Overload is
defined as the load current exceeding its normal level
due to an unexpected abnormal event. In this situation,
the protection circuit should trigger to protect the power
supply. However, even when the power supply is in the
normal condition, the overload situation can occur during
the load transition. To avoid premature triggering of
protection, the overload protection circuit should be
designed to trigger only after a specified time to
determine whether it is a transient situation or a true
overload situation. Figure 26 shows a typical overload
protection circuit. By sensing the resonant capacitor
voltage on the control pin, the overload protection can be
implemented. Using RC time constant, shutdown delay
can be also introduced. The voltage obtained on the
control pin is given as:
VCON
CB
VCr p p
2(C B Csense )
p-p
where VCr
voltage.
PCB Layout Guidelines
Duty unbalance problems may occur due to the radiated
noise from main transformer, the inequality of the
secondary side leakage inductances of main transformer,
and so on. Among them, it is one of the dominant
reasons that the control components in the vicinity of RT
pin are enclosed by the primary current flow pattern on
PCB layout. The direction of the magnetic field on the
components caused by the primary current flow is
changed when the high and low side MOSFET turns on
by turns. The magnetic fields with opposite direction from
each other induce a current through, into, or out of the RT
pin, which makes the turn-on duration of each MOSFET
different. It is highly recommended to separate the
control components in the vicinity of RT pin from the
primary current flow pattern on PCB layout. Figure 28
shows an example for the duty balanced case.
Figure 28. Example for Duty Balancing
(7)
is the amplitude of the resonant capacitor
© 2010 Fairchild Semiconductor Corporation
FSFR2100 • Rev.1.1.0
www.fairchildsemi.com
12
FSFR2100 — Fairchild Power Switch (FPS™) for Half-Bridge Resonant Converters
6.6
Over-Voltage Protection (OVP): When the
LVCC reaches 23 V, OVP is triggered. This protection is
used when auxiliary winding of the transformer to supply
VCC to FPS™ is utilized.
6.2
Latch-Mode Protection: Once this protection is
triggered, switching is terminated and the MOSFETs
remain off. The latch is reset only when LVCC is
discharged below 5 V.
Application
FPS™ Device
Input Voltage Range
Rated Output Power
Output Voltage
(Rated Current)
LCD TV
FSFR2100
390 VDC
(340~400 VDC)
200 W
24 V-8.3 A
Features
High efficiency ( >94% at 400 VDC input)
Reduced EMI noise through zero-voltage-switching (ZVS)
Enhanced system reliability with various protection functions
Figure 29. Typical Application Circuit
© 2010 Fairchild Semiconductor Corporation
FSFR2100 • Rev.1.1.0
www.fairchildsemi.com
13
FSFR2100 — Fairchild Power Switch (FPS™) for Half-Bridge Resonant Converters
Typical Application Circuit (Half-Bridge LLC Resonant Converter)
Usually, LLC resonant converters require large leakage inductance value. To obtain a large leakage inductance,
sectional winding method is used.
Core: EC35 (Ae=106 mm2)
Bobbin: EC35 (Horizontal)
Transformer Model Number: SNX-2468-1
Figure 30. Transformer Construction
Pin (S → F)
Wire
Turns
Note
Np
6→2
0.08φ×88 (Litz Wire)
36
Ns1
12 → 9
0.08φ×234 (Litz Wire)
4
Bifilar Winding
Ns2
10 → 13
0.08φ×234 (Litz Wire)
4
Bifilar Winding
Pins
Specifications
Remark
Primary-Side Inductance (Lp)
2 6
550 H ± 10%
100 kHz, 1 V
Primary-Side Effective Leakage (Lr)
2 6
110 H ± 10%
Short one of the Secondary Windings
For more detailed information regarding the transformer, visit http://www.santronics-usa.com/documents.html or contact
sales@santronics-usa.com or +1-408-734-1878 (Sunnyvale, California USA).
© 2010 Fairchild Semiconductor Corporation
FSFR2100 • Rev.1.1.0
www.fairchildsemi.com
14
FSFR2100 — Fairchild Power Switch (FPS™) for Half-Bridge Resonant Converters
Typical Application Circuit (Continued)
26.20
25.80
3.40
3.00
23.10
22.90
1.20
R0.50 (4X)
10.70
10.30
5.35
5.15
12.00
14.50
13.50
18.50
17.50
0.70
3.20
R0.55
R0.55
8.00 1.30 MAX
7.00
5.08
0.80 MAX
1
2,4,6,8
9
0.70
0.50
2.54
1.27 (5X)
15.24
0.60
0.40
3.48
2.88
FRONT VIEW
RIGHT SIDE VIEW
3.40
3.00
R0.50
BOTTOM VIEW
NOTES: UNLESS OTHERWISE SPECIFIED
A. THIS PACKAGE DOES NOT COMPLY TO
ANY CURRENT PACKAGING STANDARD.
B. ALL DIMENSIONS ARE IN MILLIMETERS.
C. DIMENSIONS ARE EXCLUSIVE OF BURRS,
MOLD FLASH AND TIE BAR PROTRUSIONS.
D. DRAWING FILE NAME: MOD09ACREV3
1,3,5,7,9
1.40
1.00
2.54
3.81
1.50
6.00
ON Semiconductor and
are trademarks of Semiconductor Components Industries, LLC dba ON Semiconductor or its subsidiaries in the United States and/or other countries.
ON Semiconductor owns the rights to a number of patents, trademarks, copyrights, trade secrets, and other intellectual property. A listing of ON Semiconductor’s product/patent
coverage may be accessed at www.onsemi.com/site/pdf/Patent−Marking.pdf. ON Semiconductor reserves the right to make changes without further notice to any products herein.
ON Semiconductor makes no warranty, representation or guarantee regarding the suitability of its products for any particular purpose, nor does ON Semiconductor assume any liability
arising out of the application or use of any product or circuit, and specifically disclaims any and all liability, including without limitation special, consequential or incidental damages.
Buyer is responsible for its products and applications using ON Semiconductor products, including compliance with all laws, regulations and safety requirements or standards,
regardless of any support or applications information provided by ON Semiconductor. “Typical” parameters which may be provided in ON Semiconductor data sheets and/or
specifications can and do vary in different applications and actual performance may vary over time. All operating parameters, including “Typicals” must be validated for each customer
application by customer’s technical experts. ON Semiconductor does not convey any license under its patent rights nor the rights of others. ON Semiconductor products are not
designed, intended, or authorized for use as a critical component in life support systems or any FDA Class 3 medical devices or medical devices with a same or similar classification
in a foreign jurisdiction or any devices intended for implantation in the human body. Should Buyer purchase or use ON Semiconductor products for any such unintended or unauthorized
application, Buyer shall indemnify and hold ON Semiconductor and its officers, employees, subsidiaries, affiliates, and distributors harmless against all claims, costs, damages, and
expenses, and reasonable attorney fees arising out of, directly or indirectly, any claim of personal injury or death associated with such unintended or unauthorized use, even if such
claim alleges that ON Semiconductor was negligent regarding the design or manufacture of the part. ON Semiconductor is an Equal Opportunity/Affirmative Action Employer. This
literature is subject to all applicable copyright laws and is not for resale in any manner.
PUBLICATION ORDERING INFORMATION
LITERATURE FULFILLMENT:
Literature Distribution Center for ON Semiconductor
19521 E. 32nd Pkwy, Aurora, Colorado 80011 USA
Phone: 303−675−2175 or 800−344−3860 Toll Free USA/Canada
Fax: 303−675−2176 or 800−344−3867 Toll Free USA/Canada
Email: orderlit@onsemi.com
© Semiconductor Components Industries, LLC
N. American Technical Support: 800−282−9855 Toll Free
USA/Canada
Europe, Middle East and Africa Technical Support:
Phone: 421 33 790 2910
Japan Customer Focus Center
Phone: 81−3−5817−1050
www.onsemi.com
1
ON Semiconductor Website: www.onsemi.com
Order Literature: http://www.onsemi.com/orderlit
For additional information, please contact your local
Sales Representative
www.onsemi.com
工商网监
湘ICP备2023018690号
