Fairchild FS8S0765RCB Fairchild power switch (fpsâ ¢) Datasheet

FS8S0765RCB
Fairchild Power Switch (FPS™)
Features
Description
„ Burst Mode Operation to Reduce the Power
FS8S0765RCB is a Fairchild Power Switch (FPS) that is
specially designed for off-line SMPS of CRT monitors
with minimal external components. This device is a
current mode pulse-width modulated (PWM) controller
combined with a high-voltage power SenseFET in a single
package. The PWM controller features integrated
oscillator to be synchronized with the external sync
signal, under-voltage lockout, optimized gate driver,
temperature compensated precise current sources for
the loop compensation. This device also includes
various fault-protection, circuits such as over voltage
protection, overload protection, abnormal over current
protection and over-temperature protection, Compared
with a discrete MOSFET and PWM controller solution,
FPS can reduce total cost, component count, size, weight,
while increasing efficiency, productivity, and system
reliability. This device is well suited for the cost-effective
monitor power supply.
„
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„
„
„
„
„
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„
Consumption in the Standby Mode
External pin for Synchronization and Soft Start
Wide Operating Frequency Range up to 150kHz
Low Start-up Current (Max:80μA)
Low Operating Current (Max:15mA)
Pulse by Pulse Current Limiting
Over-Voltage Protection (Auto Restart Mode)
Overload Protection (Auto Restart Mode)
Abnormal Over-Current Protection (Auto Restart
Mode)
Internal Thermal Shutdown (Auto Restart Mode)
Under-Voltage Lockout
Internal High-Voltage SenseFET
Applications
„ SMPS for Monitor
TO-220-5L
1
1. Drain 2. GND 3. VCC 4. Feedback 5. Sync
Ordering Information
Product Number
FS8S0765RCBTU
Package
(1)
FS8S0765RCBYDTU
(2)
Marking Code
BVDSS
RDS(ON)
8S0765RC
650V
1.6Ω
TO-220-5L
TO-220-5L (Forming)
Notes:
1. TU: Non Forming Type
2. YDTU: Forming Type
FPSTM is a trademark of Fairchild Semiconductor Corporation.
©2006 Fairchild Semiconductor Corporation
FS8S0765RCB Rev. 1.0.2
1
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FS8S0765RCB Fairchild Power Switch (FPS™)
April 2006
Vcc
3
Vref
Drain
1
Vcc Good
Burst Mode Detector
Vfb<0.8V
Vss>3V
No sync
Soft start 5
& Sync
Burst Mode
Controller
Vcc
Internal
Bias
OSC
Vref
Idelay
FB
9V/15V
Vref
Sync
Detector
Vref
PWM
IFB
4
2.5R
R
S
Q
R
Q
Gate
driver
LEB
V SD
Vcc
Vovp
TSD
UVLO Reset
(Vcc<9V)
S
Q
R
Q
2 GND
AOCP
Vocl
Figure 1. Functional Block Diagram
FS8S0765RCB Rev. 1.0.2
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FS8S0765RCB Fairchild Power Switch (FPS™)
Internal Block Diagram
FS8S0765RC
5. Soft Start & Sink
4. Feedback
3. Vcc
2. GND
1. Drain
Figure 2. Pin Configuration (Top View)
Pin Definitions
Pin Number
Pin Name
Pin Function Description
1
Drain
SenseFET Drain. High voltage power SenseFET drain connection. This pin is
designed to drive the transformer directly.
2
GND
Ground. Control ground and the SenseFET source.
3
Vcc
Supply Voltage. Supply input. This pin provides internal operating current for
both start-up and steady-state operation.
4
Feedback
Feedback. Internally connected to the inverting input of the PWM comparator.
For stable operation, a capacitor should be placed between this pin and GND.
If the voltage of this pin reaches 7.5V, the overload protection is activated,
resulting in shutdown of FPS.
5
Soft Start & Sync
FS8S0765RCB Rev. 1.0.2
Soft Start and Sync. For soft-start and synchronization to the external sync
signal.
3
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FS8S0765RCB Fairchild Power Switch (FPS™)
Pin Configuration
The “Absolute Maximum Ratings” are those values beyond which the safety of the device cannot be guaranteed. The
device should not be operated at these limits. The parametric values defined in the Electrical Characteristics tables
are not guaranteed at the absolute maximum ratings. The “Recommended Operating Conditions” table defines the
conditions for actual device operation. (TA = 25°C, unless otherwise specified)
Symbol
Value
Unit
VDSS
Drain-Source (GND) Voltage
(1)
650
V
VDGR
Drain-Gate Voltage (RGS=1MΩ)
650
V
Gate-Source (GND) Voltage
±30
V
Drain Current Pulsed (2)
28
Single Pulsed Avalanche Energy (3)
ADC
370
mJ
IAS
Single Pulsed Avalanche Current (4)
17
A
ID
Continuous Drain Current (Tc = 25°C)
7
ADC
ID
Continuous Drain Current (Tc=100°C)
4.5
ADC
40
V
-0.3 to Vcc
V
VGS
IDM
EAS
VCC
VFB
VS_S
PD (Watt H/S)
Derating
Parameter
Supply Voltage
Input Voltage Range
Total Power Dissipation
V
145
W
1.16
W/°C
+150
°C
Operating Ambient Temperature
-25 to +85
°C
Storage Temperature Range
-55 to +150
°C
Tj
Operating Junction Temperature
TA
TSTG
-0.3 to 10
Notes:
1. Tj=25°C to 150°C
2. Repetitive rating: Pulse width limited by maximum junction temperature
3. L=14mH, starting Tj=25°C
4. L=13μH, starting Tj=25°C
FS8S0765RCB Rev. 1.0.2
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FS8S0765RCB Fairchild Power Switch (FPS™)
Absolute Maximum Ratings
(TA = 25°C unless otherwise specified)
Symbol
Parameter
BVDSS
Drain Source Breakdown Voltage
IDSS
Zero Gate Voltage Drain Current
RDS(ON)
gfs
Forward Transconductance
Ciss
Input Capacitance
Coss
Output Capacitance
Crss
td (on)
tr
td (off)
tf
Condition
Static Drain Source On Resistance (1)
Min.
Typ.
Max.
Unit
VGS=0V, ID=250μA
650
-
-
V
VDS=650V, VGS=0V
-
-
200
μA
VDS=520V
VGS=0V, TC=125°C
-
-
300
μA
VGS=10V, ID=3.5A
-
1.4
1.6
W
VDS=40V, ID=3.5A
-
8
-
mho
VGS=0V, VDS=25V,
f = 1MHz
-
1415
-
-
100
-
-
15
-
-
25
-
Reverse Transfer Capacitance
Turn On Delay Time
Rise Time
VDD=325V, ID=6.5A (2)
Turn Off Delay Time
Fall Time
Qg
Total Gate Charge
(Gate-Source+Gate-Drain)
Qgs
Gate-Source Charge
Qgd
Gate-Drain (Miller) Charge
VGS=10V, ID=6.5A,
VDS=325V (2)
-
60
-
-
115
-
-
65
-
-
40
-
-
7
-
-
12
-
pF
nS
nC
Note:
1. Pulse test: Pulse width ≤ 300μS, duty 2%
2. MOSFET switching time is essentially independent of operating temperature.
FS8S0765RCB Rev. 1.0.2
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FS8S0765RCB Fairchild Power Switch (FPS™)
Electrical Characteristics (SenseFET part)
(TA=25°C unless otherwise specified)
Symbol
Parameter
Condition
Min.
Typ. Max.
Unit
UVLO Section
VSTART
Start Threshold Voltage
VFB=GND
14
15
16
V
VSTOP
Stop Threshold Voltage
VFB=GND
8
9
10
V
Oscillator Section
FOSC
Initial Frequency
FSTABLE
Voltage Stability
ΔFOSC
Temperature Stability (1)
18
20
22
kHz
12V ≤ VCC ≤ 23V
0
1
3
%
-25°C ≤ TA ≤ 85°C
0
±5
±10
%
DMAX
Maximum Duty Cycle
92
95
98
%
DMIN
Minimum Duty Cycle
-
-
0
%
Feedback Section
IFBSO
Feedback Source Current
VFB=GND
0.7
0.9
1.1
mA
IFBSI
Feedback Sink Current
VFB=4V,VCC=19V
2.4
3.0
3.6
mA
VSD
Shutdown Feedback Voltage
VFB ≥ 6.9V
6.9
7.5
8.1
V
Shutdown Delay Current
VFB=5V
1.6
2.0
2.4
μA
VCC ≥ 27V
34
37
-
V
0.95
1.0
1.05
V
140
160
-
°C
4.7
5.0
5.3
V
Idelay
Protection Section
VOVP
Over Voltage Protection
VOCL
Over Current Latch Voltage
TSD
(2)
Thermal Shutdown Temp. (1)
Sync & Soft-start Section
VSS
Soft start Voltage
ISS
Soft start Current
VSS=0V
0.8
1.0
1.2
mA
VSH
Sync High Threshold Voltage
VCC=16V,VFB=5V
6.7
7.2
7.9
V
VSL
Sync Low Threshold Voltage
VCC=16V,VFB=5V
5.4
5.8
6.2
V
12
12.6
V
VFB=2
Burst Mode Section (DPMS Mode)
VBUH
Burst Mode High Threshold Voltage
VFB=0V
11.6
VBUL
Burst Mode Low Threshold Voltage
VFB=0V
10.6
11
11.6
V
VBUFB
Burst Mode Enable FB Voltage
VCC=10.5V
0.9
1.0
1.1
V
VBUSS
Burst Mode Enable S_S Voltage
VCC=10.5V,VFB=0V
2.5
3.0
3.5
V
TBUDT
FBU
Burst Mode Enable Delay Time
VCC=10.5V,VFB=0V
-
0.5
-
ms
Burst Mode Frequency
VCC=10.5V,VFB=0V
32
40
48
kHz
Current Limit (Self-Protection) Section
IOVER
Peak Current Limit (3)
3.52
4.0
4.48
A
IBU_PK
Burst Mode Peak Current Limit
0.45
0.6
0.75
A
-
40
80
μA
-
9
15
mA
Total Device Section
ISTART
IOP
IOP(MIN)
Start Up Current
Operating Supply Current (4)
IOP(MAX)
VCC=Vstart-0.1V
VFB=GND, VCC=16V
VFB=GND, VCC=12V
VFB=GND, VCC=27V
Note:
1. These parameters, although guaranteed at the design, are not tested in mass production.
2. These parameters, although guaranteed, are tested in EDS (wafer test) process.
3. These parameters indicate inductor current.
4. These parameters are the current flowing in the control IC.
FS8S0765RCB Rev. 1.0.2
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FS8S0765RCB Fairchild Power Switch (FPS™)
Electrical Characteristics (Continued)
1.20
1.20
1.15
1.15
1.10
1.10
1.05
Normalized to 25 °C
Normalized to 25 °C
(These characteristic graphs are normalized at TA = 25°C)
1.00
0.95
0.90
0.85
-20
0
20
40
60
80
1.00
0.95
0.90
0.85
0.80
100 120 140 160
-40
-20
0
20
80
100 120 140 160
Figure 3. Start Up Current vs. Temp.
Figure 4. Operating Supply Current vs. Temp.
1.20
1.15
1.15
1.10
1.10
1.05
1.00
0.95
0.90
1.05
1.00
0.95
0.90
0.85
0.85
0.80
-40
-20
0
20
40
60
80
0.80
-40
100 120 140 160
-20
0
20
40
60
80
100 120 140 160
Temperature [°C]
Temperature [°C]
Figure 5. Start Threshold Voltage vs. Temp.
Figure 6. Stop Threshold Voltage vs. Temp.
1.20
1.20
1.15
1.15
1.10
1.10
Normalized to 25 °C
Normalized to 25 °C
60
Temperature [°C]
1.20
1.05
1.00
0.95
0.90
1.05
1.00
0.95
0.90
0.85
0.85
0.80
-40
40
Temperature [°C]
Normalized to 25 °C
Normalized to 25 °C
0.80
-40
1.05
-20
0
20
40
60
80
0.80
-40
100 120 140 160
0
20
40
60
80
100 120 140 160
Temperature [°C]
Temperature [°C]
Figure 8. Maximum Duty Cycle vs. Temp.
Figure 7. Initial Freqency vs. Temp.
FS8S0765RCB Rev. 1.0.2
-20
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FS8S0765RCB Fairchild Power Switch (FPS™)
Typical Performance Characteristics (Control Part)
1.7
1.20
1.6
1.5
1.15
1.4
1.10
Normalized to 25 °C
Normalized to 25 °C
(These characteristic graphs are normalized at TA= 25°C)
1.3
1.2
1.1
1.0
0.9
0.8
0.7
0.6
1.05
1.00
0.95
0.90
0.85
0.5
-40
-20
0
20
40
60
80
0.80
-40
100 120 140 160
-20
0
20
60
80
100 120 140 160
Temperature [°C]
Temperature [°C]
Figure 10. Feedback Sink Current vs. Temp.
Figure 9. Feedback Offset Voltage vs. Temp.
1.20
1.20
1.15
1.15
1.10
1.10
Normalized to 25 °C
Normalized to 25 °C
40
1.05
1.00
0.95
0.90
1.05
1.00
0.95
0.90
0.85
0.85
0.80
-40
-20
0
20
40
60
80
0.80
-40
100 120 140 160
-20
0
20
40
60
80
100 120 140 160
Temperature [°C]
Figure 11. Shutdown Delay Current vs. Temp.
Figure 12. Shutdown Feedback Voltage vs. Temp.
1.20
1.20
1.15
1.15
1.10
1.10
Normalized to 25 °C
Normalized to 25 °C
Temperature [°C]
1.05
1.00
0.95
0.90
0.85
1.05
1.00
0.95
0.90
0.85
0.80
-40
-20
0
20
40
60
80
0.80
-40
100 120 140 160
0
20
40
60
80
100 120 140 160
Temperature [°C]
Temperature [°C]
Figure 14. Over Voltage Protection vs. Temp.
Figure 13. Soft Start Voltage vs. Temp.
FS8S0765RCB Rev. 1.0.2
-20
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FS8S0765RCB Fairchild Power Switch (FPS™)
Typical Performance Characteristics (Continued)
1.20
1.20
1.15
1.15
1.10
1.10
Normalized to 25 °C
Normalized to 25 °C
(These characteristic graphs are normalized at TA= 25°C)
1.05
1.00
0.95
0.90
1.00
0.95
0.90
0.85
0.85
0.80
-40
1.05
-20
0
20
40
60
80
0.80
-40
100 120 140 160
-20
0
20
Temperature [°C]
1.3
1.15
Normalized to 25 °C
Normalized to 25 °C
1.20
1.2
100 120 140 160
1.1
1.0
0.9
1.10
1.05
1.00
0.95
0.90
0.85
-20
0
20
40
60
80
0.80
-40
100 120 140 160
-20
0
20
40
60
80
100 120 140 160
Temperature [°C]
Temperature [°C]
Figure 17. Feedback Sink Current vs. Temp.
Figure 18. Burst Mode Low Threshold Voltage vs. Temp.
1.20
1.20
1.15
1.15
1.10
1.10
Normalized to 25 °C
Normalized to 25 °C
80
Figure 16. Peak Current vs. Temp.
1.4
1.05
1.00
0.95
0.90
0.85
0.80
-40
60
Temperature [°C]
Figure 15. Normal Mode Regulation Voltage vs. Temp.
0.8
-40
40
1.05
1.00
0.95
0.90
0.85
-20
0
20
40
60
80
0.80
-40
100 120 140 160
0
20
40
60
80
100 120 140 160
Temperature [°C]
Temperature [°C]
Figure 19. Burst Mode High Threshold Voltage vs. Temp.
FS8S0765RCB Rev. 1.0.2
-20
9
Figure 20. Burst Mode Enable Voltage vs. Temp.
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FS8S0765RCB Fairchild Power Switch (FPS™)
Typical Performance Characteristics (Continued)
FS8S0765RCB Fairchild Power Switch (FPS™)
Typical Performance Characteristics (Continued)
(These characteristic graphs are normalized at TA= 25°C)
1.20
Normalized to 25 °C
1.15
1.10
1.05
1.00
0.95
0.90
0.85
0.80
-40
-20
0
20
40
60
80
100 120 140 160
Temperature [°C]
Figure 21. Burst Mode Peak Current vs. Temp.
FS8S0765RCB Rev. 1.0.2
10
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3. Protection function: FS8S0765RCB has four selfprotective functions such as abnormal over current
protection (AOCP), overload protection (OLP), overvoltage protection (OVP) and thermal shutdown (TSD).
Because these protection circuits are fully integrated into
the IC without external components, the reliability can be
improved without cost increase. In the event of these
fault conditions, the FPS enters into auto-restart
operation. Once the fault condition occurs, switching
operation is terminated and MOSFET remains off, which
forces Vcc to be reduced. When Vcc reaches 9V, the
protection is reset and the supply current reduces to 80
μA. Then, Vcc begin to increase with the current
provided through the start-up resistor. When Vcc
reaches 15V, the FPS resumes normal operation if the
fault condition is removed. In this manner, the autorestart alternately enables and disables the switching of
the power MOSFET until the fault condition is eliminated,
as illustrated in Figure 24.
1. Start up: To guarantee stable operation of the control
IC, FS8S0765RCB has UVLO circuit with 6V hysteresis
band. Figure 22 shows the relation between the supply
current (Icc) and the supply voltage (Vcc). Before Vcc
reaches 15V, the FPS consumes only startup current of
80mA, which is usually provided by the DC link through
the start-up resistor. When Vcc reaches 15V, the FPS
begins operation and the operating current increases to
15mA as shown. Once the control IC starts operation, it
continues normal operation until Vcc goes below the
stop voltage of 9V.
Icc
15mA
Protection is activated
(OCP,OLP,OVP or TSD)
V
Vds
80uA
Vstop=9V
Vstart=15V
OVP
Vcc
Figure 22. High Voltage Current Source
2. Feedback Control: FS8S0765RCB employs primary
side regulation, which permits elimination of feedback
circuit components in the secondary side, such as optocoupler and TL431. Figure 23 shows the primary side
control circuit. The primary side regulation voltage (Vpsr)
is controlled to the breakdown voltage of zener diode
(Dz). Because current mode control is employed, the
drain current of the power MOSFET is limited by the
inverting input of PWM comparator (Vfb*). When
MOSFET turns on, usually there exists high current
spike in the MOSFET current caused by primary-side
capacitance and secondary-side rectifier reverse
recovery. To prevent premature termination of the
switching pulse due to the current spike, the FPS
employs leading edge blanking (LEB). The leading edge
blanking circuit inhibits the PWM comparator for a short
time after the MOSFET is turned on.
Vcc
V psr
Vfb
DZ
15V
9V
Vcc
Figure 24. Auto restart operation after
protection
3.1 Abnormal Over Current Protection (AOCP): When
the secondary rectifying diodes or the transformer pins
are shorted, a steep current with extremely high di/dt can
flow during the LEB time. Therefore, the abnormal overcurrent protection (AOCP) block is added to ensure the
reliability, as shown in Figure 25. It turns off the
SenseFET within 300ns after the abnormal over-current
condition is sensed.
FB
4
OVP
OSC
D1
Cfb
D2
OLP
TSD
2.5R
Vfb*
Gate
driver
R
S Q'
GATE
DRIVER
SenseFE
T
R
RZ
UVLO
V SD
Auto restart
time
Vref
0.9m
A
2uA
time
V
Vcc
PWM Comp
OLP
AOCP COMP.
Vsense : 1V
Figure 23. Pulse-Width Modulation (PWM)
Circuit
FS8S0765RCB Rev. 1.0.2
Figure 25. AOCP block
11
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FS8S0765RCB Fairchild Power Switch (FPS™)
Functional Description
3.3 Over Voltage Protection (OVP): In case of
malfunction in the primary side feedback circuit or
feedback loop open caused by a defect of solder, the
current through primary side control transistor becomes
almost zero. Then, Vfb climbs up in a similar manner to
the overload situation, forcing the preset maximum
current to be supplied to the secondary side until the
over load protection is activated. Because more energy
than required is provided to the output, the output
voltage may exceed the rated voltage before the over
load protection is activated, resulting in the breakdown of
the devices in the secondary side. To prevent this
situation, an over-voltage protection (OVP) circuit is
employed. When the Vcc voltage touches 37V, the OVP
block is activated.
3.4 Thermal Shutdown (TSD): The SenseFET and the
control IC are built in one package. This allows the
control IC to detect the heat generation from the
SenseFET. If the temperature exceeds approximately
160°C, the thermal shutdown is activated.
V
Vds
4. Soft Start: Figure 28 shows the soft-start circuit.
During the initial start up, the 0.9 mA current source
leaks out through Css and Rss. As Css is charged, the
leakage current decreases. By choosing much bigger
Css than Cfb, it is possible to increase the feedback
voltage slowly, forcing the SenseFET current to increase
slowly. After Css reaches its steady state value, D3 is
blocked and the soft switching circuit is decoupled from
the feedback circuit. If the value of Css is too large, there
is possibility that Vfb increases to 7.5V, activating the
over load protection during soft start time. To avoid this
situation, it is recommended that the value of Css should
not exceed 100 times the Cfb.
time
V
22V
15V
Vcc
9V
Auto restart
Overload protection
V
time
7.5V
Vfb
time
Vref
50K
Figure 26. The waveforms at the OLP and auto
restart
Css
5
Rss
D3
VFB
2.5R
Cfb
Overload protection
D
OSC
4
2μA
PWM
COMP.
S
GATE
DRIVER
0.9mA
R
7.5V
Voffset
FS8S0765RCB
2.7V
Figure 28. The circuit for the soft start
T12= Cfb*(7.5-2.7)/Idelay
T1
T2
t
Figure 27. Overload protection
FS8S0765RCB Rev. 1.0.2
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FS8S0765RCB Fairchild Power Switch (FPS™)
3.2 Overload Protection (OLP): When the load current
exceeds a preset level for longer than the predetermined time, protection circuit should be activated to
protect the SMPS. Because of the pulse-by-pulse
current limit capability, the maximum peak current
through the SMPS is limited, and the maximum input
power is restricted with a given input voltage. If the
output consumes beyond this maximum power, the
output voltage, together with primary side regulation
voltage, decrease below the set voltage. This reduces
the current through primary side regulation transistor,
which increases feedback voltage (Vfb). If Vfb exceeds
2.7V, D1 is blocked and the 2μA current source starts to
charge Cfb slowly, compared to when the 0.9mA current
source charges Cfb. In this condition, Vfb continues
increasing until it reaches 7.5V and the switching
operation is terminated at that time, as shown in Figure
27. The delay time for shutdown is the time required to
charge Cfb from 2.7V to 7.5V with 2μA.
operation. At the end of the section 3, the load is
eliminated and the feedback voltage (Vfb) drops below
1V, forcing the FPS to stop switching operation. During
the section 4, Vcc goes down to 11V. During section 5,
Vcc is hysteresis controlled between 11V and 12V.
When the external sync signal is applied on the pin 5, the
FPS resumes normal operation. To minimize the power
consumption in standby mode, it is recommended to set
the value of Vcc during normal operation as high as
possible (about 29V).
V
5V
Vsync
3V
Vref
V
Vfb
SYNC COMP.
Css
5
7.2V
External
Sync
Rss
5.8V
D3
1V
D
OSC
4
Cfb
2.5R
2μA
PWM
COMP.
V
S
GATE
DRIVER
0.9mA
Vds
R
Voffset
FS8S0765RCB
V
Vcc
Figure 29. The circuit for the synchronization
with external sync
Vcc
15V
12V
11V
9V
6. Burst mode operation: To minimize the power
dissipation at standby mode, FS8S0765RCB has a burst
mode operation. In burst mode, the FPS reduces the
effective switching frequency and output voltage. The
FPS enters burst mode when the voltage of the soft start
pin is higher than 3V. No sync signal is applied and the
feedback voltage is lower than 1V. During the burst
mode operation, Vcc is hysteresis controlled between
11V and 12V. Once the FPS enters burst mode, it stops
switching operation until Vcc drops to 11V. When Vcc
reaches 11V, the FPS starts switching with switching
frequency of 40kHz and peak MOSFET current of 0.6A
until Vcc reaches 12V. When Vcc reaches 12V, the
switching operation is terminated again until Vcc reduces
to 11V. Figure 30 shows operating waveforms. The soft
start during the initial start-up is shown in the section 1.
During this period, there is no external sync signal and
the switching frequency is 20kHz. The section 2
represents the normal mode operation. The switching
frequency is synchronized with the external sync signal.
In the section 3, the external sync signal is removed;
however, the load still exists and the feedback voltage
(Vfb) is higher than 1V. In this period, the FPS does the
normal switching operation with switching frequency of
20kHz. The section 4 and 5 show the burst mode
FS8S0765RCB Rev. 1.0.2
Section 4
Section I
Section 2
Section 3
Section 5
Section 6 time
Figure 30. The operation of the FS8S0765RCB
at the normal mode and the off mode
13
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FS8S0765RCB Fairchild Power Switch (FPS™)
5. Synchronization: To reduce the effect of switching
noise on the screen, the SMPS for monitor synchronizes
its switching frequency to an external signal, typically the
horizontal sync flyback signal. The switching frequency
of the FPS can vary from 20 kHz to 150 kHz according to
the external sync signal. The internal sync comparator
detects the sync signal and determines the SenseFET
turn-on time. The SenseFET is turned on at the negative
edge of the sync comparator output. The reference voltage of the sync comparator is an inverted saw tooth with
a base frequency of 20kHz and a varying range between
5.8V and 7.2V, as shown in the Figure 29. The inverted
saw tooth reference gets rid of the excessive switching
noise at the first synchronized turn-on. The external sync
signal is recommended to have an amplitude higher than
4.2V.
1. 80W Universal Input Power Supply For CRT Monitor
T1
D201
L201
BD101
3
C107
10nF/630V
C106
220μF/400V
+
R101
56K/2W
+
-
1
16
2
15
3
14
C201
22μF/160V
+
R102
3.3
D102
5
4
3
C110
1μF/50V
+
C104
4.7nF
C102
100nF
C108
22μF/50V
Vcc
+
1
Drain
2
GND
8
C206
1000μF/25V
L204
C207
1000μF/25V
7
+
C208
1000μF/25V
R105
560
ZD101
6.2VZD
2N3904
10
C111
0.1μF
C109
47nF
C101
TNR
14V
D204
D103
C114
1nF
+
-14V
D205
L205
C112
47μF/16V
+
R106
100
9
C301
4.7nF
F101
FUSE
+
C205
1000μF/25V
11
FS8S0765RCB
R104
2.2K
50V
L203
S/S
+
C103
4.7nF
12
C204
47μF/100V
D203
IC101
Vfb
+
C203
47μF/100V
13
6
100nF
Line Filter: LF101
80V
L202
D101
4
C105
C202
22μF/160V
D202
4
R103
600K
0
RT101
+
+
+ 2
1
+
C209
1000μF/16V
C210
1000μF/16V
6.5V
C302
4.7nF
0
Regulator ouput_5V
C113
1μF
Sync trans
Hsync_O
2
0.1μF
1nF
1N4148
1
C115
Micro
controller
DC5
V
R201
0.1K
0
R202
4k
KSC945
R203
0.7k
Off
signal
On --> normal mode:
Off --> off mode
2. Transformer Schematic Diagram
Lm : 420uH
1
16
15
14
Np : 40T
13
12
4
11
6
10
Nvcc : 12T
Nreg : 3T
FS8S0765RCB Rev. 1.0.2
Nvo2 : 22T
Nvo3 : 6T
Nvo4 : 5T
Nvo5 : 3T
7
8
Nvo1 : 10T
9
14
www.fairchildsemi.com
FS8S0765RCB Fairchild Power Switch (FPS™)
Typical Application Circuit
No
Pin (s→f)
Wire
Turns
Winding Method
4→1
φ
40
Solenoid Winding
10
Center Winding
3
Solenoid Winding
22
Center Winding
40
Solenoid Winding
6
Solenoid Winding
5
Solenoid Winding
3
Solenoid Winding
12
Solenoid Winding
Np1
0.3 × 1
Insulation: Polyester Tape t = 0.050mm, 2 Layers
16 → 15
Nvo1
0.3φ × 1
Insulation: Polyester Tape t = 0.050mm, 2 Layers
7→8
Nreg
0.2φ × 1
Insulation: Polyester Tape t = 0.050mm, 2 Layers
14 → 13
Nvo2
0.3φ × 3
Insulation: Polyester Tape t = 0.050mm, 2 Layers
4→1
Np2
0.3φ × 1
Insulation: Polyester Tape t = 0.050mm, 2 Layers
12 → 9
Nvo3
0.3φ × 2
Insulation: Polyester Tape t = 0.050mm, 2 Layers
9 → 11
Nvo4
0.3φ × 1
Insulation: Polyester Tape t = 0.050mm, 2 Layers
10 → 9
Nvo5
0.3φ × 2
Insulation: Polyester Tape t = 0.050mm, 2 Layers
6→8
Nvcc
0.2φ × 1
Outer Insulation: Polyester Tape t = 0.050mm, 2 Layers
4. Electrical Characteristics
Pin
Specification
Remarks
Inductance
1-4
420μH ± 10%
300kHz, 1V
Leakage Inductance
1-4
5μH Max
2nd all short
5. Core & Bobbin
„ Core: EER 3540
„ Bobbin: EER3540
„ Ae(mm2): 107
FS8S0765RCB Rev. 1.0.2
15
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FS8S0765RCB Fairchild Power Switch (FPS™)
3. Winding Specification
Part
Value
Note
Fuse
F101
3A/250V
RT101
10D-9
NTC
Resistor
R101
Part
Value
Note
C201
22nF/160V
Electrolytic Capacitor
C202
22nF/160V
Electrolytic Capacitor
C203
47nF/100V
Electrolytic Capacitor
C204
47nF/100V
Electrolytic Capacitor
C205
1000nF/25V
Electrolytic Capacitor
56kΩ
2W
C206
1000nF/25V
Electrolytic Capacitor
R102
3.3Ω
1/4W
C207
1000nF/25V
Electrolytic Capacitor
R103
600kΩ
1W
C208
1000nF/25V
Electrolytic Capacitor
R104
2.2kΩ
1/4W
C209
1000nF/25V
Electrolytic Capacitor
R105
0.56kΩ
1/4W
C210
1000nF/25V
Electrolytic Capacitor
R106
0.1kΩ
1/4W
C211
0.1μF/50V
Ceramic Capacitor
R201
0.1kΩ
1/4W
C301
4.7nF
AC Filter Capacitor
R202
4kΩ
1/4W
C302
4.7nF
AC Filter Capacitor
R203
0.7kΩ
1/4W
Sync
trans
22mH
Inductor
L201 ~ L205
13uH
Diode
Capacitor
D101
UF4007
D102
TVR10G
C101
471D10
TNR
D103
TVR10G
C102
100nF
Box Capacitor
D201
UF4007
C103
4.7nF
AC Filter Capacitor
D202
UF5404
C104
4.7nF
AC Filter Capacitor
D203
UF5402
C105
100nF
Box Capacitor
D204
UF5402
C106
220μF/400V
Electrolytic Capacitor
D205
UF5401
C107
10nF/630V
Ceramic Capacitor
C108
22μF/50V
Electrolytic Capacitor
BD101
KBL406
C109
47nF/50V
Ceramic Capacitor
C110
1μF/50V
Electrolytic Capacitor
LF101
24mH
C111
0.1μF/50V
Ceramic Capacitor
C112
47μF/50V
Electrolytic Capacitor
IC101
FS8S0765RC
(7A, 650V)
IC201
KSC945
NPN Transistor
C113
1μF/50v
Electrolytic Capacitor
C114
1nF/50V
Ceramic Capacitor
C115
1nF/50V
Ceramic Capacitor
FS8S0765RCB Rev. 1.0.2
Bridge Diode
Line Filter
IC
16
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FS8S0765RCB Fairchild Power Switch (FPS™)
6. Demo Circuit Part List
TO-220-5L
Dimensions in millimeters
June 2002, Rev. C
FS8S0765RCB Rev. 1.0.2
17
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FS8S0765RCB Fairchild Power Switch (FPS™)
Package Dimensions
TO-220-5L (Forming)
Dimensions in millimeters
June 2002, Rev. A
FS8S0765RCB Rev. 1.0.2
18
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FS8S0765RCB Fairchild Power Switch (FPS™)
Package Dimensions (Continued)
The following are registered and unregistered trademarks Fairchild Semiconductor owns or is authorized to use and is not
intended to be an exhaustive list of all such trademarks.
ACEx™
FAST®
FASTr™
ActiveArray™
FPS™
Bottomless™
FRFET™
Build it Now™
GlobalOptoisolator™
CoolFET™
GTO™
CROSSVOLT™
HiSeC™
DOME™
I2C™
EcoSPARK™
i-Lo™
E2CMOS™
EnSigna™
ImpliedDisconnect™
FACT™
IntelliMAX™
FACT Quiet Series™
Across the board. Around the world.™
The Power Franchise®
Programmable Active Droop™
ISOPLANAR™
LittleFET™
MICROCOUPLER™
MicroFET™
MicroPak™
MICROWIRE™
MSX™
MSXPro™
OCX™
OCXPro™
OPTOLOGIC®
OPTOPLANAR™
PACMAN™
POP™
Power247™
PowerEdge™
PowerSaver™
PowerTrench®
QFET®
QS™
QT Optoelectronics™
Quiet Series™
RapidConfigure™
RapidConnect™
μSerDes™
ScalarPump™
SILENT SWITCHER®
SMART START™
SPM™
Stealth™
SuperFET™
SuperSOT™-3
SuperSOT™-6
SuperSOT™-8
SyncFET™
TCM™
TinyLogic®
TINYOPTO™
TruTranslation™
UHC™
UniFET™
UltraFET®
VCX™
Wire™
DISCLAIMER
FAIRCHILD SEMICONDUCTOR RESERVES THE RIGHT TO MAKE CHANGES WITHOUT FURTHER NOTICE TO ANY
PRODUCTS HEREIN TO IMPROVE RELIABILITY, FUNCTION OR DESIGN. FAIRCHILD DOES NOT ASSUME ANY
LIABILITY ARISING OUT OF THE APPLICATION OR USE OF ANY PRODUCT OR CIRCUIT DESCRIBED HEREIN;
NEITHER DOES IT CONVEY ANY LICENSE UNDER ITS PATENT RIGHTS, NOR THE RIGHTS OF OTHERS. THESE
SPECIFICATIONS DO NOT EXPAND THE TERMS OF FAIRCHILD’S WORLDWIDE TERMS AND CONDITIONS,
SPECIFICALLY THE WARRANTY THEREIN, WHICH COVERS THESE PRODUCTS.
LIFE SUPPORT POLICY
FAIRCHILD’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT
DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF FAIRCHILD SEMICONDUCTOR
CORPORATION.
As used herein:
1. Life support devices or systems are devices or systems
which, (a) are intended for surgical implant into the body,
or (b) support or sustain life, or (c) whose failure to perform
when properly used in accordance with instructions for use
provided in the labeling, can be reasonably expected to
result in significant injury to the user.
2. A critical component is any component of a life support
device or system whose failure to perform can be
reasonably expected to cause the failure of the life support
device or system, or to affect its safety or effectiveness.
PRODUCT STATUS DEFINITIONS
Definition of Terms
Datasheet Identification
Product Status
Definition
Advance Information
Formative or In
Design
This datasheet contains the design specifications for
product development. Specifications may change in
any manner without notice.
Preliminary
First Production
This datasheet contains preliminary data, and
supplementary data will be published at a later date.
Fairchild Semiconductor reserves the right to make
changes at any time without notice in order to improve
design.
No Identification Needed
Full Production
This datasheet contains final specifications. Fairchild
Semiconductor reserves the right to make changes at
any time without notice in order to improve design.
Obsolete
Not In Production
This datasheet contains specifications on a product
that has been discontinued by Fairchild semiconductor.
The datasheet is printed for reference information only.
Rev. I19
FS8S0765RCB Rev. 1.0.2
19
www.fairchildsemi.com
FS8S0765RCB Fairchild Power Switch (FPS™)
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