Fairchild FSD210BM Green mode fairchild power switch (fps) for valley switching converter - low emi and high efficiency Datasheet

FSQ510, FSQ510H, and FSQ510M
Green Mode Fairchild Power Switch (FPS™)
for Valley Switching Converter – Low EMI and High Efficiency
Features
Description
ƒ Uses an LDMOS Integrated Power Switch
ƒ Optimized for Valley Switching Converter (VSC)
ƒ Low EMI through Variable Frequency Control and
A Valley Switching Converter (VSC) generally shows
lower EMI and higher power conversion efficiency than
a conventional hard-switched converter with a fixed
switching frequency. The FSQ510 (H or M) is an
integrated valley switching pulse width modulation (VSPWM) controller and SenseFET specifically designed
for offline switch-mode power supplies (SMPS) for
valley switching with minimal external components. The
VS-PWM controller includes an integrated oscillator,
under-voltage lockout (UVLO), leading-edge blanking
(LEB), optimized gate driver, internal soft-start,
temperature-compensated precise current sources for
loop compensation, and self-protection circuitry.
Inherent Frequency Modulation
ƒ High Efficiency through Minimum Drain Voltage
Switching
ƒ Extended Valley Switching for Wide Load Ranges
ƒ Small Frequency Variation for Wide Load Ranges
ƒ Advanced Burst-Mode Operation for Low Standby
Power Consumption
Compared with discrete MOSFET and PWM controller
solutions, the FSQ510 (H or M) can reduce total cost,
component count, size and weight; while simultaneously
increasing efficiency, productivity, and system reliability.
This device provides a platform for cost-effective designs
of a valley switching flyback converters.
ƒ Pulse-by-Pulse Current Limit
ƒ Protection Functions: Overload Protection (OLP),
Internal Thermal Shutdown (TSD) with Hysteresis
ƒ Under-Voltage Lockout (UVLO) with Hysteresis
ƒ Internal Startup Circuit
ƒ Internal High-Voltage SenseFET: 700V
ƒ Built-in Soft-Start: 5ms
Applications
ƒ Auxiliary
Power Supplies for LCD TV, LCD Monitor,
Personal Computer, and White Goods
Ordering Information
(1)
Output Power Table
Operating
Current RDS(ON) 230VAC ± 15%(2)
Replaces
Part
85-265VAC
Junction
Package Eco
Limit (MAX)
Devices
Number
Open
Open
(3)
(3)
Status Temperature
Adapter
(4) Adapter
(4)
Frame
Frame
FSQ510
7-DIP
FSD210B
FSQ510H
8-DIP
FSQ510M
7-MLSOP
RoHS -40 to +130°C 320mA
32Ω
5.5W
9W
4W
6W
FSD210DH
FSD210BM
For Fairchild’s definition of “green” Eco Status, please visit: http://www.fairchildsemi.com/company/green/rohs_green.html.
Notes:
1. The junction temperature can limit the maximum output power.
2. 230VAC or 100/115VAC with voltage doubler.
3. Typical continuous power with a Fairchild charger evaluation board described in this datasheet in a nonventilated, enclosed adapter housing, measured at 50°C ambient temperature.
4. Maximum practical continuous power for auxiliary power supplies in an open-frame design at 50°C ambient temperature.
© 2008 Fairchild Semiconductor Corporation
FSQ510, FSQ510H, and FSQ510M • Rev. 1.2.0
www.fairchildsemi.com
FSQ510, FSQ510H, and FSQ510M — Green Mode Fairchild Power Switch (FPS™) for Valley Switching Converter
September 2008
Vo
AC
IN
Vstr
D
Sync
VS
-PWM
Vfb
GND
Vcc
Figure 1.
Typical Application Circuit
Internal Block Diagram
Sync
VCC
Vstr
D
4 (3)
5 (7)
8 (1)
7 (8)
200 ns
delay
VREF
Idelay
Vfb
IFB
3
(2)
UVLO
0.7V / 0.1V
VREF
8.7V / 6.7V
VREF
OSC
S
6R
Q
R
R
360ns
LEB
Rsense
0.85V / 0.75V
(0.4V)
S/S
5ms
OLP
4.7V
S
TSD
Q
A/R
R
n(m):n stands for the pin number of 7-DIP and 7-MLSOP
m stands for the pin number of 8-DIP
1,2
(4,5,6)
GND
Figure 2.
© 2008 Fairchild Semiconductor Corporation
FSQ510, FSQ510H, and FSQ510M • Rev. 1.2.0
Internal Block Diagram
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FSQ510, FSQ510H, and FSQ510M — Green Mode Fairchild Power Switch (FPS™) for Valley Switching Converter
Application Circuit
Vstr
D
Vfb
Vcc
FSQ510H
Figure 3.
Sync
GND
GND
GND
Package Diagrams for FSQ510(M) and FSQ510H
Pin Definitions
7-Pin
8-Pin
Name
1, 2
4, 5, 6
GND
3
2
Vfb
4
3
Sync
5
7
VCC
7
8
D
8
1
© 2008 Fairchild Semiconductor Corporation
FSQ510, FSQ510H, and FSQ510M • Rev. 1.2.0
Vstr
Description
This pin is the control ground and the SenseFET source.
This pin is internally connected to the inverting input of the PWM
comparator. The collector of an opto-coupler is typically tied to this
pin. For stable operation, a capacitor should be placed between this
pin and GND. If the voltage of this pin reaches 4.7V, the overload
protection triggers, which shuts down the FPS.
This pin is internally connected to the sync-detect comparator for
valley switching. In normal valley-switching operation, the threshold of
the sync comparator is 0.7V/0.1V.
This pin is the positive supply input. This pin provides internal
operating current for both startup and steady-state operation.
High-voltage power SenseFET drain connection.
This pin is connected directly, or through a resistor, to the highvoltage DC link. At startup, the internal high-voltage current source
supplies internal bias and charges the external capacitor connected
to the VCC pin. Once VCC reaches 8.7V, the internal current source is
disabled.
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FSQ510, FSQ510H, and FSQ510M — Green Mode Fairchild Power Switch (FPS™) for Valley Switching Converter
Pin Assignments
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.
Symbol
Parameter
Min.
Max.
Unit
VSTR
Vstr Pin Voltage
500
V
VDS
Drain Pin Voltage
700
V
VCC
Supply Voltage
20
V
VFB
Feedback Voltage Range
-0.3
6.5
V
Sync Pin Voltage
-0.3
6.5
V
VSync
7-DIP
PD
Total Power Dissipation
1.38
7-MLSOP
8-DIP
Maximum Junction Temperature
TJ
TSTG
W
1.47
+150
Recommended Operating Junction
(5)
Temperature
-40
+140
Storage Temperature
-55
+150
°C
°C
Notes:
5. The maximum value of the recommended operating junction temperature is limited by thermal shutdown.
Thermal Impedance
TA=25°C unless otherwise specified. Items are tested with the standards JESD 51-2 and 51-10 (DIP).
Symbol
Parameter
Value
Unit
90
°C/W
13
°C/W
85
°C/W
13
°C/W
7-DIP, 7-MLSOP
θJA
Junction-to-Ambient Thermal Impedance
θJC
Junction-to-Case Thermal Impedance
θJA
Junction-to-Ambient Thermal Impedance
(6)
(7)
8-DIP
θJC
Junction-to-Case Thermal Impedance
(6)
(7)
Notes:
6. Free-standing with no heatsink; without copper clad; measurement condition - just before junction temperature
TJ enters into TSD.
7. Measured on the DRAIN pin close to plastic interface.
© 2008 Fairchild Semiconductor Corporation
FSQ510, FSQ510H, and FSQ510M • Rev. 1.2.0
www.fairchildsemi.com
4
FSQ510, FSQ510H, and FSQ510M — Green Mode Fairchild Power Switch (FPS™) for Valley Switching Converter
Absolute Maximum Ratings
T J=25°C unless otherwise specified.
Symbol
Parameter
Conditions
Min.
Typ.
Max.
Unit
SenseFET Section
BVDSS
Drain-Source Breakdown Voltage
VCC=0V, ID=100μA
IDSS
Zero-Gate-Voltage Drain Current
VDS=700V
RDS(ON)
Drain-Source On-State Resistance
(8)
700
V
150
TJ=25°C, ID=180mA
28
32
TJ=100°C, ID=180mA
42
48
μA
CISS
Input Capacitance
VGS=11V
96
pF
COSS
Output Capacitance(8)
VDS=40V
28
pF
Rise Time(8)
VDS=350V, ID=25mA
100
ns
VDS=350V, lD=25mA
50
ns
tr
tf
(8)
Fall Time
Control Section
fS
Initial Switching Frequency
87.7
94.3
±5
±8
%
VCC=11V, VFB=0V
200
225
250
μA
VCC=11V, VFB=1V,
Vsync Frequency Sweep
7.2
7.6
8.2
μs
VCC=11V, VFB=3V
54
60
66
%
0
%
VFB=0V, VCC Sweep
8.0
8.7
9.4
V
After Turn-on, VFB=0V
6.0
6.7
7.4
V
VSTR=40V, VCC Sweep
3
5
7
ms
0.75
0.85
0.95
V
0.65
0.75
0.85
VCC=11V, VFB=0.5V, Vsync=0V
ΔfS
Switching Frequency Variation(8)
-25°C < TJ < 125°C
IFB
Feedback Source Current
tBB
Switching Blanking Time
tBW
Valley Detection Window Time(8)
DMAX
Maximum Duty Ratio
DMIN
Minimum Duty Ratio
VSTART
VSTOP
Internal Soft-Start Time
tS/S
Burst-Mode Section
VBURH
VBURL
Burst-Mode Voltage
VCC=11V, VFB Sweep
HYS
kHz
μs
3.0
VCC=11V, VFB=0V
UVLO Threshold Voltage
100.0
100
V
mV
Protection Section
ILIM
Peak Current Limit
di/dt=90mA/µs
280
320
360
mA
VSD
Shutdown Feedback Voltage
VDS=40V, VCC=11V,
VFB Sweep
4.2
4.7
5.2
V
4
5
6
3.5
4.5
5.5
IDELAY
tLEB
TSD
HYS
Shutdown Delay
Current
FSQ510H
FSQ510(M)
VCC=11V, VFB=5V
Leading-Edge Blanking Time(8)
360
130
Thermal Shutdown Temperature(8)
140
μA
ns
150
°C
°C
60
Synchronous Section
VSH
VSL
tSync
Synchronous Threshold Voltage
VCC=11V, VFB=1V
0.55
0.70
0.85
V
VCC=11V, VFB=1V
0.05
0.10
0.15
V
180
200
220
ns
Synchronous Delay Time
Total Device Section
IOP
Operating Supply Current
(Control Part Only)
VCC=11V, VFB=5.5V
0.8
1.0
mA
ICH
Startup Charging Current
VCC=VFB=0V,VSTR=40V
1.0
1.2
mA
Supply Voltage
VCC=VFB=0V, VSTR Sweep
VSTR
Note:
8. These parameters, although guaranteed, are not 100% tested in production.
© 2008 Fairchild Semiconductor Corporation
FSQ510, FSQ510H, and FSQ510M • Rev. 1.2.0
27
V
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FSQ510, FSQ510H, and FSQ510M — Green Mode Fairchild Power Switch (FPS™) for Valley Switching Converter
Electrical Characteristics
T
Function
FSD210B
FSQ510
Control Mode
Voltage Mode
Current Mode
Operation Method
Constant Frequency
PWM
Valley Switching
Operation
Turn-on at Minimum Drain Voltage
High Efficiency and Low EMI
EMI Reduction
Method
Frequency
Modulation
Valley Switching
Frequency Variation Depending on the Ripple
of DC Link Voltage
High Efficiency and Low EMI
Soft-Start
3ms (Built-in)
5ms (Built-in)
Protection
TSD
Power Balance
Long TCLD
Short TCLD
Power Ratings
Less than 5W
Under Open-Frame
Condition at the
Universal Line Input
More than 6W
Under Open-Frame
Condition at the
Universal Line Input
© 2008 Fairchild Semiconductor Corporation
FSQ510, FSQ510H, and FSQ510M • Rev. 1.2.0
Advantages of FSQ510
Fast Response
Easy-to-Design Control Loop
Longer Soft-Start Time
TSD with Hysteresis Enhanced Thermal Shutdown Protection
Small Difference of Input Power between the
Low and High Input Voltage Cases
More Output Power Rating Available due to the
Valley Switching
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FSQ510, FSQ510H, and FSQ510M — Green Mode Fairchild Power Switch (FPS™) for Valley Switching Converter
Comparison between FSD210B and FSQ510
1.20
1.20
1.15
1.15
1.10
1.10
Normalized
Normalized
Characteristic graphs are normalized at TA=25°C.
1.05
1.00
0.95
1.05
1.00
0.95
0.90
0.90
0.85
0.85
0.80
-40
-25
0
25
50
75
100
0.80
-40
125
-25
0
Temperature [℃]
Operating Frequency (fOSC) vs. TA
Figure 5.
1.20
1.20
1.15
1.15
1.10
1.10
Normalized
Normalized
Figure 4.
1.05
1.00
0.95
0.85
25
50
75
100
0.80
-40
125
-25
0
Figure 7.
1.20
1.15
1.15
1.10
1.10
Normalized
Normalized
Start Threshold Voltage (VSTART) vs. TA
1.05
1.00
0.95
0.85
50
75
100
0.80
-40
125
Temperature [℃]
Figure 8.
125
Stop Threshold Voltage (VSTOP) vs. TA
-25
0
25
50
75
100
125
Temperature [℃]
Shutdown Feedback Voltage (VSD) vs. TA
© 2008 Fairchild Semiconductor Corporation
FSQ510, FSQ510H, and FSQ510M • Rev. 1.2.0
100
0.95
0.90
25
75
1.00
0.85
0
50
1.05
0.90
-25
25
Temperature [℃]
1.20
0.80
-40
125
Peak Current Limit (ILIM) vs. TA
Temperature [℃]
Figure 6.
100
0.95
0.90
0
75
1.00
0.85
-25
50
1.05
0.90
0.80
-40
25
Temperature [℃]
Figure 9.
Maximum Duty Cycle (DMAX) vs. TA
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FSQ510, FSQ510H, and FSQ510M — Green Mode Fairchild Power Switch (FPS™) for Valley Switching Converter
Typical Performance Characteristics
1.20
1.15
1.15
1.10
1.10
Normalized
Normalized
1.20
1.05
1.00
0.95
1.05
1.00
0.95
0.90
0.90
0.85
0.85
0.80
-40
-25
0
25
50
75
100
0.80
-40
125
Temperature [℃]
-25
0
25
50
75
100
125
Temperature [℃]
Figure 10. Feedback Source Current (IFB) vs. TA
Figure 11. Shutdown Delay Current (IDELAY) vs. TA
1.20
1.15
Normalized
1.10
1.05
1.00
0.95
0.90
0.85
0.80
-40
-25
0
25
50
75
100
125
Temperature [℃]
Figure 12. Operating Supply Current (IOP) vs. TA
© 2008 Fairchild Semiconductor Corporation
FSQ510, FSQ510H, and FSQ510M • Rev. 1.2.0
www.fairchildsemi.com
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FSQ510, FSQ510H, and FSQ510M — Green Mode Fairchild Power Switch (FPS™) for Valley Switching Converter
Typical Performance Characteristics (Continued)
2.2 Leading-Edge Blanking (LEB): At the instant the
internal SenseFET is turned on, a high-current spike
usually occurs through the SenseFET, caused by
primary-side capacitance and secondary-side rectifier
reverse recovery. Excessive voltage across the Rsense
resistor would lead to incorrect feedback operation in
the current mode VS-PWM control. To counter this
effect, the FPS employs a leading-edge blanking
(LEB) circuit to inhibit the VS-PWM comparator for a
short time (tLEB) after the SenseFET is turned on.
1. Startup: At startup, an internal high-voltage current
source supplies the internal bias and charges the
external capacitor (Ca) connected to the VCC pin, as
illustrated in Figure 13. When VCC reaches 8.7V, the
FPS begins switching and the internal high-voltage
current source is disabled. The FPS continues normal
switching operation and the power is supplied from the
auxiliary transformer winding unless VCC goes below the
stop voltage of 6.7V.
VDC
Vref
Ca
Vref
Idelay
VO
FOD817
Vfb
3
D1
OB
VCC
D2
+
Vfb *
Vstr
5
VS signal
I FB
8
KA431
6R
Gate
driver
R
-
ICH
OLP
VSD
6.7V/
8.7V
SenseFET
OSC
R sense
Vref
VCC good
Internal
Bias
Figure 13. Startup Block
2. Feedback Control: This device employs currentmode control, as shown in Figure 14. An opto-coupler
(such as the FOD817) and shunt regulator (such as the
KA431) are typically used to implement the feedback
network. Comparing the feedback voltage with the
voltage across the Rsense resistor makes it possible to
control the switching duty cycle. When the reference pin
voltage of the shunt regulator exceeds the internal
reference voltage of 2.5V, the opto-coupler LED current
increases, pulling down the feedback voltage and
reducing the drain current. This typically occurs when the
input voltage is increased or the output load is decreased.
Figure 14. Valley Switching Pulse-Width
Modulation (VS-PWM) Circuit
3. Synchronization: The FSQ510 (H or M) employs a
valley-switching technique to minimize the switching
noise and loss. The basic waveforms of the valley
switching converter are shown in Figure 15. To
minimize the MOSFET switching loss, the MOSFET
should be turned on when the drain voltage reaches its
minimum value, as shown in Figure 15. The minimum
drain voltage is indirectly detected by monitoring the
VCC winding voltage, as shown in Figure 15.
B
B
V DS
V RO
V RO
V DC
2.1 Pulse-by-Pulse Current Limit: Because currentmode control is employed, the peak current through the
SenseFET is limited by the inverting input of PWM
comparator (VFB*), as shown in Figure 14. Assuming
that the 225µA current source flows only through the
internal resistor (6R + R=12.6kΩ), the cathode voltage
of diode D2 is about 2.8V. Since D1 is blocked when
the feedback voltage (VFB) exceeds 2.8V, the maximum
voltage of the cathode of D2 is clamped at this voltage,
clamping VFB*. Therefore, the peak value of the current
through the SenseFET is limited.
tF
V Sync
0.7V
0.1V
200ns Delay
MOSFET
Gate
ON
ON
Figure 15. Valley Switching Waveforms
© 2008 Fairchild Semiconductor Corporation
FSQ510, FSQ510H, and FSQ510M • Rev. 1.2.0
www.fairchildsemi.com
9
FSQ510, FSQ510H, and FSQ510M — Green Mode Fairchild Power Switch (FPS™) for Valley Switching Converter
Functional Description
B
most applications. This protection is implemented in
auto-restart mode.
VFB
Overload Protection
4.7V
B
Vds
Power
on
Fault
occurs
6.7V
Normal
operation
t
Figure 16. Auto Restart Protection Waveforms
4.1 Overload Protection (OLP): Overload is defined as
the load current exceeding its normal level due to an
unexpected event. In this situation, the protection circuit
should trigger to protect the SMPS. However, even
when the SMPS is in the normal operation, the overload
protection circuit can be triggered during the load
transition. To avoid this undesired operation, the
overload protection circuit is designed to trigger only
after a specified time to determine whether it is a
transient situation or a true overload situation. Because
of the pulse-by-pulse current limit capability, the
maximum peak current through the SenseFET is limited
and, therefore, the maximum input power is restricted
with a given input voltage. If the output consumes more
than this maximum power, the output voltage (Vo)
decreases below the set voltage. This reduces the
current through the opto-coupler LED, which also
reduces the opto-coupler transistor current, increasing
the feedback voltage (VFB). If VFB exceeds 2.8V, D1 is
blocked and the 5µA current source starts to charge CB
slowly up. In this condition, VFB continues increasing
until it reaches 4.7V, when the switching operation is
terminated, as shown in Figure 17. The delay time for
shutdown is the time required to charge CB from 2.8V to
4.7V with 5µA. A 20 ~ 50ms delay time is typical for
© 2008 Fairchild Semiconductor Corporation
FSQ510, FSQ510H, and FSQ510M • Rev. 1.2.0
t1
t2
t
4.2 Thermal Shutdown (TSD): The SenseFET and the
control IC on a die in one package make it easy for the
control IC to detect the abnormal over temperature of
the SenseFET. If the temperature exceeds
approximately 140°C, the thermal shutdown triggers
and the FPS stops operation. The FPS operates in
auto-restart mode until the temperature decreases to
around 80°C, when normal operation resumes.
8.7V
Fault
situation
t12= CB•(4.7-2.8)/Idelay
Figure 17. Overload Protection
Fault
removed
VCC
Normal
operation
2.8V
5. Soft-Start: The FPS has an internal soft-start circuit
that increases the VS-PWM comparator inverting input
voltage, together with the SenseFET current, slowly
after it starts up. The typical soft-start time is 5ms. The
pulse width to the power switching device is
progressively increased to establish the correct working
conditions for transformers, inductors, and capacitors.
The voltage on the output capacitors is progressively
increased with the intention of smoothly establishing the
required output voltage. This helps prevent transformer
saturation and reduces stress on the secondary diode
during startup.
6. Burst-Mode Operation: To minimize power
dissipation in standby mode, the FPS enters burstmode operation. As the load decreases, the feedback
voltage decreases. As shown in Figure 18, the device
automatically enters burst mode when the feedback
voltage drops below VBURL (750mV). At this point,
switching stops and the output voltages start to drop at
a rate dependent on standby current load. This causes
the feedback voltage to rise. Once it passes VBURH
(850mV), switching resumes. The feedback voltage
then falls and the process repeats. Burst mode
alternately enables and disables switching of the
SenseFET, reducing switching loss in standby mode.
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FSQ510, FSQ510H, and FSQ510M — Green Mode Fairchild Power Switch (FPS™) for Valley Switching Converter
4. Protection Circuits: The FSQ510 (H or M) has two
self-protective functions, overload protection (OLP) and
thermal shutdown (TSD). The protections are
implemented as auto-restart mode. Once the fault
condition is detected, switching is terminated and the
SenseFET remains off. This causes VCC to fall. When
VCC falls down to the under-voltage lockout (UVLO) stop
voltage of 6.7V, the protection is reset and the startup
circuit charges the VCC capacitor. When VCC reaches
the start voltage of 8.7V, the FSQ510 (H or M) resumes
normal operation. If the fault condition is not removed,
the SenseFET remains off and VCC drops to stop
voltage again. In this manner, the auto-restart can
alternately enable and disable the switching of the
power SenseFET until the fault condition is eliminated.
Because these protection circuits are fully integrated
into the IC without external components, reliability is
improved without increasing cost.
Voset
VFB
B
0.85V
0.75V
T smax=10.6 µs
Ids
IDS
Ids
A
tB=7.6µs
T s_A
Vds
IDS
IDS
B
tB=7.6µs
time
Switching
disabled
t1
t2 t3
Switching
disabled
T s_B
t4
Figure 18. Burst-Mode Operation
IDS
7. Advanced Valley Switching Operation: To
minimize
switching
loss
and
Electromagnetic
Interference (EMI), the MOSFET turns on when the
drain voltage reaches its minimum value in VS
converters. Due to the Discontinuous Conduction Mode
(DCM) operation, the feedback voltage is not changed,
despite the DC link voltage ripples, if the load condition
is not changed. Since the slope of the drain current is
changed depending on the DC link voltage, the turn-on
duration of MOSFET is variable with the DC link voltage
ripples. The switching period is changed continuously
with the DC link voltage ripples. Not only the switching
at the instant of the minimum drain voltage, but also the
continuous change of the switching period, reduces
EMI. VS converters inherently scatter the EMI spectrum.
Typical products for VSC turn the MOSFET on when the
first valley is detected. In this case, the range of the
switching frequency is very wide as a result of the load
variations. At a very light-load, for example, the
switching frequency can be as high as several hundred
kHz. Some products for VSC, such as Fairchild’s
FSCQ-series, define the turn-on instant of SenseFET
change at the first valley into at the second valley, when
the load condition decreases under its predetermined
level. The range of switching frequency narrows
somewhat. For details, consult an FSCQ-series
datasheet, such as:
http://www.fairchildsemi.com/pf/FS/FSCQ1265RT.html
C
tB=7.6µ s
T s_C
IDS
IDS
tB=7.6µ s
tW=3µs
D
T smax=10.6 µs
Figure 19. Advanced VS Operation
When the resonant period is 2µs
132 kHz
A
B
C
Con stant
frequency
104 kHz
94.3kHz
D
Bur st
mode
The range of the switching frequency can be limited
tightly in FSQ-series. Because a kind of blanking time
(tB) is adopted, as shown in Figure 19, the switching
frequency has minimum and maximum values.
© 2008 Fairchild Semiconductor Corporation
FSQ510, FSQ510H, and FSQ510M • Rev. 1.2.0
IDS
Po
Figure 20. Switching Frequency Range of the
Advanced Valley Switching
www.fairchildsemi.com
11
FSQ510, FSQ510H, and FSQ510M — Green Mode Fairchild Power Switch (FPS™) for Valley Switching Converter
Once the SenseFET is enabled, the next start is
prohibited during the blanking time (tB). After the
blanking time, the controller finds the first valley within
the duration of the valley detection window time (tW )
(case A, B, and C). If no valley is found in tW , the
internal SenseFET is forced to turn on at the end of tW
(case D). Therefore, FSQ510, FSQ510H, and
FSQ510M have minimum switching frequency of
94.3kHz and maximum switching frequency of 132kHz,
typically, as shown in Figure 20.
Vo
Figure 21. 7-Lead, Dual In-line Package (DIP)
Package drawings are provided as a service to customers considering Fairchild components. Drawings may change in any manner
without notice. Please note the revision and/or date on the drawing and contact a Fairchild Semiconductor representative to verify
or obtain the most recent revision. Package specifications do not expand the terms of Fairchild’s worldwide terms and conditions, specifically
the warranty therein, which covers Fairchild products.
Always visit Fairchild Semiconductor’s online packaging area for the most recent package drawings:
http://www.fairchildsemi.com/packaging/.
© 2008 Fairchild Semiconductor Corporation
FSQ510, FSQ510H, and FSQ510M • Rev. 1.2.0
www.fairchildsemi.com
12
FSQ510, FSQ510H, and FSQ510M — Green Mode Fairchild Power Switch (FPS™) for Valley Switching Converter
Package Dimensions
9.83
9.00
6.67
6.096
8.255
7.61
3.683
3.20
5.08 MAX
7.62
0.33 MIN
3.60
3.00
(0.56)
2.54
0.356
0.20
0.56
0.355
9.957
7.87
1.65
1.27
7.62
NOTES: UNLESS OTHERWISE SPECIFIED
A) THIS PACKAGE CONFORMS TO
JEDEC MS-001 VARIATION BA
B) ALL DIMENSIONS ARE IN MILLIMETERS.
C) DIMENSIONS ARE EXCLUSIVE OF BURRS,
MOLD FLASH, AND TIE BAR EXTRUSIONS.
D) DIMENSIONS AND TOLERANCES PER
ASME Y14.5M-1994
E) DRAWING FILENAME AND REVSION: MKT-N08FREV2.
Figure 22. 8-Lead, Dual In-line Package (DIP)
Package drawings are provided as a service to customers considering Fairchild components. Drawings may change in any manner
without notice. Please note the revision and/or date on the drawing and contact a Fairchild Semiconductor representative to verify
or obtain the most recent revision. Package specifications do not expand the terms of Fairchild’s worldwide terms and conditions, specifically
the warranty therein, which covers Fairchild products.
Always visit Fairchild Semiconductor’s online packaging area for the most recent package drawings:
http://www.fairchildsemi.com/packaging/.
© 2008 Fairchild Semiconductor Corporation
FSQ510, FSQ510H, and FSQ510M • Rev. 1.2.0
www.fairchildsemi.com
13
FSQ510, FSQ510H, and FSQ510M — Green Mode Fairchild Power Switch (FPS™) for Valley Switching Converter
Package Dimensions (Continued)
MKT-MLSOP07ArevA
Figure 23. 7-Lead, MLSOP
Package drawings are provided as a service to customers considering Fairchild components. Drawings may change in any manner
without notice. Please note the revision and/or date on the drawing and contact a Fairchild Semiconductor representative to verify
or obtain the most recent revision. Package specifications do not expand the terms of Fairchild’s worldwide terms and conditions, specifically
the warranty therein, which covers Fairchild products.
Always visit Fairchild Semiconductor’s online packaging area for the most recent package drawings:
http://www.fairchildsemi.com/packaging/.
© 2008 Fairchild Semiconductor Corporation
FSQ510, FSQ510H, and FSQ510M • Rev. 1.2.0
www.fairchildsemi.com
14
FSQ510, FSQ510H, and FSQ510M — Green Mode Fairchild Power Switch (FPS™) for Valley Switching Converter
Package Dimensions (Continued)
FSQ510, FSQ510H, and FSQ510M — Green Mode Fairchild Power Switch (FPS™) for Valley Switching Converter
© 2008 Fairchild Semiconductor Corporation
FSQ510, FSQ510H, and FSQ510M • Rev. 1.2.0
www.fairchildsemi.com
15
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