Fairchild FAN7316MX Lcd backlight inverter drive ic Datasheet

FAN7316
LCD Backlight Inverter Drive IC
Features
Description
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The FAN7316 is a LCD backlight inverter drive IC that
controls N-N half-bridge topology. The FAN7316 can
also drive push-pull topology.
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High-Efficiency Single-Stage Power Conversion
Wide Input Voltage Range: 4.5V to 24V
Backlight Lamp Ballast and Soft Dimming
Reduces Required External Components
Precision Voltage Reference Trimmed to 2%
N-N Half-Bridge Topology
PWM Control at Fixed Frequency
Analog and Burst Dimming Function
Selectable Burst Dimming Polarity by ADIM Voltage
Striking Frequency Depending on Normal
Frequency
Open-Lamp Protection
Open-Lamp Regulation
Short-Circuit Protection
20-Pin SOIC
The FAN7316 provides a low-cost solution by integrating
the external open-lamp protection circuit. The operating
voltage of the FAN7316 is wide, so the FAN7316 doesn’t
need an external regulator to supply the voltage to the
IC. The FAN7316 has the internal bootstrap driver, so
the external fast recovery diode can be avoided.
The FAN7316 provides various protections, such as
open-lamp regulation, arc protection, open-lamp
protection, short-circuit protection, and CMP-high
protection to increase the system reliability. The
FAN7316 provides analog dimming, burst dimming, and
burst dimming polarity selection functions.
The FAN7316 is available in a 20-SOIC package.
Applications
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LCD TV
LCD Monitor
Ordering Information
Part Number
Package
Operating Temperature
Packing Method
FAN7316M
20-SOIC
-25 to +85°C
RAIL
FAN7316MX
20-SOIC
-25 to +85°C
TAPE & REEL
All packages are lead free per JEDEC: J-STD-020B standard.
Protected under U.S. patent number 5,652,479.
© 2007 Fairchild Semiconductor Corporation
FAN7316 • 1.0.1
www.fairchildsemi.com
FAN7316 — LCD Backlight Inverter Drive IC
January 2008
FAN7316 — LCD Backlight Inverter Drive IC
Block Diagram
Figure 1. Internal Block Diagram
© 2007 Fairchild Semiconductor Corporation
FAN7316 • 1.0.1
www.fairchildsemi.com
2
FAN7316 — LCD Backlight Inverter Drive IC
VB
VIN
17
OUTH
BCT/FT
18
VS
OLR
19
SCP
OLP4
20
RT
OLP3
Pin Assignments
16
15
14
13
12
11
F
OLP2
CMP
FB
BDIM
6
7
8
9
10
VREF
5
OUTL
4
GND
3
ENA
2
ADIM
1
OLP1
PXYTT
FAN7316
F : Fairchild logo
P : Assembly site code
XY : Year & weekly code
TT : Die run code
FAN7316 : Device name
Figure 2. Package Diagram
© 2007 Fairchild Semiconductor Corporation
FAN7316 • 1.0.1
www.fairchildsemi.com
3
Pin #
Name
Description
1
OLP1
2
OLP2
This pin is for open-lamp protection. If OLP is lower than 1.5V at initial operation, the IC
operates at striking mode for BCT 450 cycles. If OLP is lower than 1.5V in normal mode, the
IC is shut down after a delay of three BCT cycles.
3
CMP
4
FB
5
BDIM
This pin is for burst dimming input. The voltage range of 0.5 to 2V at this pin controls burst
mode duty cycle from 0% to 100%.
6
ADIM
This pin is for positive analog dimming input. This voltage to 2V at this pin controls the
amplitude of the lamp current.
7
ENA
This pin is for turning on/off the IC.
8
GND
Ground.
9
OUTL
Low-side driver output. The output stage can deliver about 500mA source and sink current,
typically.
10
VREF
6V reference voltage.
11
VIN
IC supply voltage.
12
VB
High-side floating supply. The bootstrap capacitor should be connected between this pin
and VS pin, which can be fed by an internal bootstrap MOSFET.
13
OUTH
High-side driver output. The output stage can deliver about 500mA source and sink current,
typically.
14
VS
High-side floating supply return. Layout care should be taken to avoid below-ground spikes
on this pin.
15
SCP
16
RT
This pin programs the switching frequency. The resistor should be connected between this
pin and ground.
17
BCT/FT
This pin programs the burst dimming frequency. A capacitor should be connected between
this pin and ground. The waveform of this pin is the triangular waveform whose amplitude is
from 0.5V to 2V. This pin voltage goes up to 4V when the IC enters shutdown mode.
18
OLR
This pin is for open-lamp regulation. If the voltage at OLR reaches 2V, the IC makes this pin
voltage be controlled not to exceed 2V. If OLR voltage is higher than 1.75V, the IC enters
shutdown mode after delays of 451 BCT cycles in striking mode and three BCT cycles in
normal mode, respectively. If this pin voltage is higher than 3V, the IC enters shutdown
mode without delay.
19
OLP4
20
OLP3
Error amplifier output. A compensation capacitor should be connected between this pin and
ground.
Error amplifier inverting input. This pin voltage is regulated at 2V or ADIM voltage.
This pin is for short-circuit protection. If SCP is higher than 2V, IC enters shutdown mode
after a delay of 32 BCT cycles.
This pin is for open lamp protection. If OLP is lower than 1.5V at initial operation, the IC
operates at striking mode for BCT 450 cycles. If OLP is lower than 1.5V in normal mode, the
IC is shut down after a delay of three BCT cycles.
© 2007 Fairchild Semiconductor Corporation
FAN7316 • 1.0.1
www.fairchildsemi.com
4
FAN7316 — LCD Backlight Inverter Drive IC
Pin Definitions
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
VIN
IC Supply Voltage
4.5
24
V
VB
High-Side Floating Supply
-0.3
33
V
(3)
VB-7
V
°C
VS
High-Side Floating Supply Return
-2
TJ
Operating Junction Temperature
-40
+150
Storage Temperature Range
-65
+150
°C
90
°C /W
1.4
W
TSTG
θJA
Thermal Resistance Junction-Air
PD
Power Dissipation
(1,2)
Notes:
1. Thermal resistance test board. Size: 76.2mm x 114.3mm x 1.6mm (1S0P); JEDEC standard: JESD51-2, JESD51-3.
2. Assume no ambient airflow.
Recommended Operating Ratings
The Recommended Operating Conditions table defines the conditions for actual device operation. Recommended
operating conditions are specified to ensure optimal performance to the datasheet specifications. Fairchild does not
recommend exceeding them or designing to absolute maximum ratings.
Symbol
Parameter
VIN
IC Supply Voltage
VB
High-Side Floating Supply
VS
High-Side Floating Supply Return
TA
Operating Ambient Temperature
Min.
Max.
Unit
4.5
22
V
VS-0.3
VS+6.5
V
(3)
25
V
-25
+85
°C
Notes:
3. The VS is tolerant to short negative transient spikes.
Pin Breakdown Voltage
Pin #
Name
Value
Unit
Pin #
Name
Value
1
OLP1
7
11
VIN
24
2
OLP2
7
12
VB
33
3
CMP
7
13
OUTH
7
4
FB
7
14
VS
33
5
BDIM
7
15
SCP
7
6
ADIM
7
16
RT
7
7
ENA
7
17
BCT/FT
7
V
8
GND
18
OLR
7
9
OUTL
7
19
OLP4
7
10
VREF
7
20
OLP3
7
© 2007 Fairchild Semiconductor Corporation
FAN7316 • 1.0.1
Unit
V
www.fairchildsemi.com
5
FAN7316 — LCD Backlight Inverter Drive IC
Absolute Maximum Ratings
For typical values, TA=25°C, VIN=18V, and -25°C ≤ TA ≤ 85°C, unless otherwise specified. Specifications to -25°C ~
85°C are guaranteed by design based on final characterization results.
Symbol
Parameter
Test Conditions
Min.
Typ.
Max.
Unit
5.76
6.00
6.24
V
VREF Section (Recommend X7R Capacitor)
V6
6V Regulation Voltage
CMP=0V
V6line
6V Line Regulation
VIN=7V, 18V
25
mV
V6load
6V Load Regulation
10µA≤16≤5mA
60
mV
Oscillator Section (Main)
Vfbth
Vcth
Vctl
FB Threshold Voltage
CT High Voltage
CT Low Voltage
ADIM=1, OLP=0V
(4)
(4)
0.45
V
2.0
V
0.5
V
Oscillator Section (Burst)
TA=25°C, BCT=10nF
288
300
312
Hz
BCT=10nF
282
300
318
Hz
foscb
Oscillation Frequency
Vbcth
BCT High Voltage
BCT=10nF
2
V
Vbctl
BCT Low Voltage
BCT=10nF
0.5
V
Vbctft
BCT Fault Voltage
SCP=2.5V
4
V
Error Amplifier Section
Gm1
Error Amplifier Trans-conductance
AV
Error Amplifier Open-loop Gain
V2
2V Regulation Voltage
CMP=1, ADIM=1V
100
(4)
360
600
50
TA=25°C, ADIM=2.5V
1.97
2.00
dB
2.03
260
lsin
CMP Sink Current
ADIM=1V, FB=2.5V
lsur1
CMP Source Current 1
CMP=1V, FB=0V
Isur2
CMP Source Current 2
Isur3
CMP Source Current 3
V
ppm/°C
66
100
134
µA
-134
-100
-66
µA
1.75V<OLR<2V
(4)
umho
OLR>2V
1.6
µA
0
µA
Under-Voltage Lockout Section (UVLO)
Vth
Start Threshold Voltage
ENA=2.5V
3.9
4.2
4.5
V
Start Threshold Voltage Hysteresis
ENA=2.5V
0.2
0.4
0.6
V
Ist
Start-up Current
VIN=Vth-0.2
20
60
150
µA
Iop
Operating Supply Current
Not switching
1.5
2.0
mA
5
V
0.7
V
150
µA
Vthhys
ENA Section
Vena
Enable State Input Voltage
Vdis
Disable Stage Input Voltage
Isb
Stand-by Current
2
ENA=0
100
Note:
4. These parameters, although guaranteed, are not 100% tested in production.
© 2007 Fairchild Semiconductor Corporation
FAN7316 • 1.0.1
www.fairchildsemi.com
6
FAN7316 — LCD Backlight Inverter Drive IC
Electrical Characteristics
For typical values, TA=25°C, VIN=18V, and -25°C ≤ TA ≤ 85°C, unless otherwise specified. Specifications to -25°C ~
85°C are guaranteed by design based on final characterization results.
Symbol
Parameter
Test Conditions
Min.
Typ.
Max.
Unit
Protection Section
Vscp
Short-Circuit Protection Voltage
1.9
2.0
2.1
V
Vcmpr
CMP Protection Voltage
2.8
3.0
3.2
V
Volp
Open-Lamp Protection Voltage
1.4
1.5
1.6
V
Vovp
Over-Voltage Protection
2.85
3.00
3.15
V
Volr1
Open-Lamp Regulation Voltage 1
1.60
1.75
1.90
V
Volr2
Open-Lamp Regulation Voltage 2
1.9
2.0
2.1
V
Volrhy
Open-Lamp Regulation Hysteresis
250
(5)
tscp
Short-Circuit Protection Delay
tcmp
CMP Protection Delay
tolp
Open-Lamp Protection Delay
tolr
Open-Lamp Regulation Delay
TSD
(5)
(5)
(5)
(5)
Thermal Shutdown
mV
Striking, foscb=300Hz
1.4
1.5
1.6
s
Normal, foscb=300Hz
80
100
120
ms
Striking, foscb=300Hz
1.4
1.5
1.6
s
Normal, foscb=300Hz
80
100
120
ms
Striking, foscb=300Hz
1.4
1.5
1.6
s
Normal, foscb=300Hz
6
10
ms
Striking, foscb=300Hz
1.4
1.5
1.6
s
Normal, foscb=300Hz
80
100
120
ms
(5)
150
°C
Output Section
fnrmo
Output Normal Frequency
fstr
Output Striking Frequency
Vouvh
OUTH Voltage Before Start-up
TA=25°C, RT=27kΩ
RT=27kΩ
TA=25°C, RT=27kΩ
RT=27kΩ
VIN=Vth-0.6
47.4
49.0
50.6
47
49
51
61.5
64.0
66.4
61
64
67
-0.45
0
0.45
kHz
kHz
V
Vouvl
OUTL Voltage Before Start-up
VIN=Vth-0.6
-0.45
0
0.45
V
Vosth
High-Side Output Voltage at VENA=0V
VIN=18V
-0.45
0
0.45
V
Vost
Low-Side Output Voltage at VENA=0V
VIN=18V
-0.45
0
0.45
V
Vohh
High-Side Output Voltage
VIN=18V
5.5
6.0
6.5
V
Vohl
Low-Side Output Voltage
VIN=18V
5.5
6.0
6.5
V
Idsurh
High-Side Output Drive Source Current
(5)
Idsinh
High-Side Output Drive Sink Current
Idsurl
Low-Side Output Drive Source Current
Idsinl
tdead
Low-Side Output Drive Sink Current
Dead Time
(5)
(5)
(5)
VIN=18V
500
mA
VIN=18V
500
mA
VIN=18V
500
mA
VIN=18V
500
mA
500
ns
(5)
Note:
5. These parameters, although guaranteed, are not 100% tested in production.
© 2007 Fairchild Semiconductor Corporation
FAN7316 • 1.0.1
www.fairchildsemi.com
7
FAN7316 — LCD Backlight Inverter Drive IC
Electrical Characteristics (Continued)
Figure 3. Start Threshold Voltage vs. Temp.
Figure 4. Start Threshold Voltage Hys. vs. Temp.
Figure 5. Start-up Current vs. Temp.
Figure 6. Standby Current vs. Temp.
Figure 7. Operating Frequency vs. Temp.
Figure 8. Striking Frequency vs. Temp.
© 2007 Fairchild Semiconductor Corporation
FAN7316 • 1.0.1
www.fairchildsemi.com
8
FAN7316 — LCD Backlight Inverter Drive IC
Typical Performance Characteristics
Figure 9. Burst Dimming Frequency vs. Temp.
Figure 10. VREF Voltage vs. Temp.
Figure 11. VREF Line Regulation Voltage vs. Temp.
Figure 12. VREF Load Regulation Voltage vs. Temp.
Figure 13. CMP Sink Current vs. Temp.
Figure 14. CMP Source Current 1 vs. Temp.
© 2007 Fairchild Semiconductor Corporation
FAN7316 • 1.0.1
www.fairchildsemi.com
9
FAN7316 — LCD Backlight Inverter Drive IC
Typical Performance Characteristics (Continued)
Figure 15. CMP Source Current 2 vs. Temp.
Figure 16. Operating Current vs. Temp.
Figure 17. Error Amplifier 2V Voltage vs. Temp.
Figure 18. Open-Lamp Protection Voltage vs. Temp.
Figure 19. Open-Lamp Regulation Voltage 2 vs. Temp.
Figure 20. Over-Voltage Protection vs. Temp.
© 2007 Fairchild Semiconductor Corporation
FAN7316 • 1.0.1
www.fairchildsemi.com
10
FAN7316 — LCD Backlight Inverter Drive IC
Typical Performance Characteristics (Continued)
Figure 21. Short-Circuit Protection Voltage vs. Temp.
Figure 22. High-Side Output Voltage vs. Temp.
Figure 23. Low-Side Output Voltage vs. Temp.
© 2007 Fairchild Semiconductor Corporation
FAN7316 • 1.0.1
www.fairchildsemi.com
11
FAN7316 — LCD Backlight Inverter Drive IC
Typical Performance Characteristics (Continued)
UVLO: The under-voltage lockout (UVLO) circuit
guarantees the stable operation of the IC’s control circuit
by stopping and starting it as a function of the VIN value.
The UVLO circuit turns on the control circuit when VIN
exceeds 4.5V. When VIN is lower than 3.9V, the IC’s
start-up current is less than 150µA.
t ch
tdch
2V
9µA
ENA: Applying voltage higher than 2V to the ENA pin
enables the IC. Applying voltage lower than 0.7V to the
ENA pin disables the IC.
-
Idch
0.5V
Internal Main Oscillator: The internal timing capacitor
(CT), 20pF, is charged by the reference current source,
which is formed by the timing resistor (RT). The RT
voltage is regulated at 1.728V. The sawtooth waveform
charges up to 2V. Once CT voltage is reached, the CT
begins discharging down to 0.5V. Next, the CT starts
charging again and a new switching cycle begins, as
shown in Figure 24. The main frequency is programmed
by adjusting the RT value. The main frequency is
calculated as:
2736
[KHz]
R T [KΩ]
+
S
Q
R
Q
BC T
18µA
fOSC ≈
Ich
-
+
Figure 25. Burst Dimming Oscillator Circuit
Analog Dimming: There are two kinds of analog
dimming polarity: positive analog dimming and negative
analog dimming.
For positive analog dimming, the lamp intensity is
controlled with the ADIM signal. The lamp intensity is
proportional to ADIM signal; as ADIM voltage increases,
the lamp intensity increases. Figure 26 shows how to
implement negative analog dimming circuit and Figure
27 shows the lamp current waveform vs. DIM in positive
analog dimming mode.
(1)
Figure 24. Main Oscillator Circuit
Figure 26. Positive Analog Implementation Circuit
The striking frequency is 1.3 times as high as the main
frequency.
Burst Dimming Oscillator: The burst capacitor timing
(BCT) is charged by the internal reference current
source. The triangular waveform charges up to 2V. Once
the BCT voltage is reached, the capacitor begins
discharging down to 0.5V. Next, the BCT starts charging
again and a new switching cycle begins, as shown in
Figure 25. The burst dimming frequency is programmed
by adjusting BCT value. The burst dimming frequency is
calculated as:
fOSCB ≈
3 • 10 3
[Hz]
BCT[nF]
(2)
Figure 27. Positive Analog Dimming Waveform
To avoid visible flicker, the burst dimming frequency
should be greater than 120Hz.
© 2007 Fairchild Semiconductor Corporation
FAN7316 • 1.0.1
www.fairchildsemi.com
12
FAN7316 — LCD Backlight Inverter Drive IC
Functional Description
Negative dimming polarity
2V
BDIM
BCT 0.5V
ADIM
Lamp
current
3.5V
0V
6V
OUTH
6V
OUTL
Figure 28. Negative Analog Implementation Circuit
Figure 31. Negative Burst Dimming Chosen
Burst Dimming: There are also two kinds of burst
dimming polarity: positive analog dimming and negative
analog dimming. The lamp intensity is controlled with the
BDIM voltage. By comparing the BDIM voltage with the
0.5~2V triangular waveform of burst dimming oscillator
(BCT), the PWM pulse is generated. The PWM pulse
controls the CMP voltage by discharging and charging
the CMP capacitor.
For positive burst dimming, when BDIM voltage is higher
than BCT voltage, the lamp current is turned on. So, 2V
on BDIM commands full brightness. The duty cycle of the
PWM pulse determines the lamp brightness. The lamp
intensity is proportional to BDIM voltage. As BDIM
voltage increases, the lamp intensity also increases.
Figure 32 shows the lamp current waveform vs. DIM in
positive analog dimming mode.
Figure 29. Negative Analog Dimming Waveform
Burst Dimming Polarity Selection: FAN7316 provides
the function to select burst dimming polarity by ADIM pin
voltages. If ADIM pin voltage is lower than 3V, positive
burst dimming is chosen. Refer to Figure 30.
Positive dimming polarity
2V
BDIM
BCT 0.5V
Positive dimming polarity
2V
BDIM
BCT 0.5V
Charge
current
100uA
CMP
Disharge
current
100uA
0.5V
0V
ADIM
3.0V
FB
0V
Lamp
current
0V
Lamp
current
6V
0V
OUTH
6V
6V
OUTH
OUTL
6V
OUTL
Figure 30. Positive Burst Dimming Chosen
If the ADIM pin voltage is higher than 3.5V, negative
dimming polarity is chosen. Refer to Figure 31.
© 2007 Fairchild Semiconductor Corporation
FAN7316 • 1.0.1
Figure 32. Positive Burst Dimming Operation
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13
FAN7316 — LCD Backlight Inverter Drive IC
For negative analog dimming, the lamp intensity is
controlled with the external DIM signal and the resistors.
The lamp intensity is inversely proportional to DIM
voltage. As DIM voltage increases, the lamp intensity
decreases. Figure 28 shows how to implement a
negative analog dimming circuit and Figure 29 shows the
lamp current waveform vs. DIM in negative analog
dimming mode.
Positive dimming polarity
2V
BDIM
BCT 0.5V
Lamp isn t ignited
OLP
Lamp is ignited
1.5V
6V
OUTH
6V
OUTL
Burst dimming disable
Burst dimming enable
Figure 33. Positive Burst Dimming Operation
Burst dimming can be implemented by not only DC
voltage, also PWM pulse as BDIM signal. Figure 34
shows how to implement burst dimming by using PWM
pulse as BDIM signal.
t ch
tdch
2V
Ich
Figure 35. Burst Dimming During Striking Mode
Output Drives: FAN7316 is designed to drive high-side
and low-side MOSFETs with symmetrical duty cycle. A
fixed dead time of 500ns is introduced between two
outputs at maximum duty cycle, as shown Figure 36.
-
9µA
+
Idch
-
S
Q
R
Q
BCT
18µA
0.5V
+
Comparator
External
Pulse Signal
Burst Signal
to Error Amplifier
BDIM
+
Figure 34. Burst Dimming Using an External Pulse
During striking mode, burst dimming operation is
disabled to guarantee the continuous striking time.
Figure 35 shows that burst dimming is disabled during
striking mode.
© 2007 Fairchild Semiconductor Corporation
FAN7316 • 1.0.1
Figure 36. MOSFETs Gate Drive Signal
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14
FAN7316 — LCD Backlight Inverter Drive IC
For negative burst dimming, when BDIM voltage is lower
than BCT voltage, the lamp current is turned on. So, 0V
on BDIM commands full brightness. The duty cycle of the
PWM pulse determines the lamp brightness. The lamp
intensity is inversely proportional to BDIM voltage. As
BDIM voltage increases, the lamp intensity decreases.
Figure 32 shows the lamp current waveform vs. DIM in
negative analog dimming mode.
CIN =
Q GATE
VGATE
(3)
The ratio between capacitors CIN and CBS is proportional
to the cyclical voltage loss:
(4)
C BS >> C IN
For example: if QGATE is 24nC and VGATE is 10V, CIN is
2.4nF. With CBS=100nF, the drop is 240mV.
The bootstrap driver introduces a voltage drop due to
MOSFET RDSON (typical value: 100Ω). The following
equation is useful to compute the voltage drop on the
bootstrap MOSFET:
VDROP = ICHARGE • R DSON → VDROP =
Q GATE
• R DSON
TCHARGE
(5)
Figure 37. Open-Lamp Regulation in Striking Mode
where QGATE is the gate charge of the external MOSFET,
RDSON is the on resistance of the bootstrap MOSFET,
and TCHARGE is the charging time of the bootstrap
capacitor.
For example: If QGATE is 24nC and TCHARGE is 10µs, the
drop on the bootstrap MOSFET is about 0.24V.
VDROP =
24nC
• 100Ω = 0.24 V
10µs
(6)
Protections: The FAN7316 has several protections:
Open-Lamp Regulation (OLR), Arc Protection, OpenLamp Protection (OLP), Short-Circuit Protection (SCP),
CMP-High Protection, and Thermal Shutdown (TSD). All
protections are latch-mode protections. The latch is reset
when VIN falls to the UVLO voltage or ENA is pulled
down to GND.
Open-Lamp Regulation: When a voltage higher than
2V is applied to the OLR pin, the IC enters regulation
mode and controls CMP voltage. The IC limits the lamp
voltage by decreasing CMP source current. If the OLR
voltage is higher than 1.75V, CMP source current
decreases from 100µA to 1.6µA. If the OLR voltage
reaches at 2V, CMP source current decreases to 0µA,
so CMP voltage remains constant and the lamp voltage
also remains constant, as shown in Figure 37. At the
same time, the counter based on BCT time starts
counting 450 cycles and 32 cycles at striking mode and
normal mode, respectively, then the IC enters shutdown,
as shown in Figure 38 and Figure 39.
Figure 38. Open-Lamp Regulation in Striking Mode
Figure 39. Open-Lamp Regulation in Normal Mode
© 2007 Fairchild Semiconductor Corporation
FAN7316 • 1.0.1
www.fairchildsemi.com
15
FAN7316 — LCD Backlight Inverter Drive IC
Bootstrap Operation: To choose the proper CBS value,
the external MOSFET can be seen as an equivalent
capacitor. This capacitor, CIN, is related to the MOSFET
total gate charge as:
Short-Circuit Protection: If SCP is higher than 2V, the
counter based on BCT time starts counting 450 cycles
and 32 cycles at striking mode and normal mode,
respectively, then the IC enters shutdown, as shown in
Figure 43 and Figure 44.
4V
Striking time=1.5s @ BCT=300Hz
2V
BCT
0.5V
OLP
1.5V
Lamp isn’t ignited
450 cycles
2V
SCP
6V
OUTH
6V
OUTL
Figure 40. Arc Protection
Open-Lamp Protection: If OLP is lower than 1.5V at
initial operation, the IC operates at striking mode for BCT
450 cycles, as shown in Figure 41. If OLP is lower than
1.5V at normal mode, the IC is shut down after a delay of
three BCT cycles, as shown in Figure 42.
Shutdown
Figure 43. Short-Circuit Protection in Striking Mode
4V
BCT
Protection Delay 100ms @ BCT=300Hz
2V
0.5V
Lamp is ignited
OLP
SCP
32 cycles
1.5V
2V
6V
6V
Shutdown
Figure 41. Open-Lamp Protection in Striking Mode
Figure 44. Short-Circuit Protection in Normal Mode
CMP-High Protection: If CMP is higher than 3V, the
counter based on BCT time starts counting 450 cycles
and 32 cycles at striking mode and normal mode,
respectively, then the IC enters shutdown, as shown in
Figure 45 and Figure 46.
Figure 42. Open-Lamp Protection in Normal Mode
© 2007 Fairchild Semiconductor Corporation
FAN7316 • 1.0.1
www.fairchildsemi.com
16
FAN7316 — LCD Backlight Inverter Drive IC
Arc Protection: If OLR voltage is higher than 3V, the IC
enters shutdown mode after a delay of two CT cycles, as
shown in Figure 40.
FAN7316 — LCD Backlight Inverter Drive IC
CMP-High Protection: If CMP is higher than 3V, the
counter based on BCT time starts counting 450 cycles
and 32 cycles at striking mode and normal mode,
respectively, then the IC enters shutdown, as shown in
Figure 45 and Figure 46.
4V
Striking time=1.5s @ BCT=300Hz
2V
BCT
0.5V
OLP
1.5V
CMP
Lamp isn’t ignited
450 cycles
3V
6V
OUTH
6V
OUTL
Shutdown
Figure 45. CMP-High Protection in Striking Mode
Figure 46. CMP-High Protection in Normal Mode
Thermal Shutdown: The IC provides the function to
detect the abnormal over-temperature. If the IC
temperature exceeds approximately 150°C, the thermal
shutdown triggers.
© 2007 Fairchild Semiconductor Corporation
FAN7316 • 1.0.1
www.fairchildsemi.com
17
Application
Device
Input Voltage Range
Number of lamps
19-Inch LCD Monitor
FAN7316
14.5±10%
4
1. Features
ƒ
ƒ
ƒ
ƒ
High-Efficiency Single-Stage Power Conversion
N-N Half-Bridge Topology
Reduces Required External Components
Enhanced System Reliability through Protection Functions
F1
C1
330u
FUSE
C2
1u
0
OLP3 OLP4
OLR
0
0
0
0
C5
10n
R2
R3
100k 100k
R1
30k
VB
VIN
VS
OUTH
SCP
RT
BCT
OLR
IC1
15V
OLP4
OLP3
1
2
3
4
5
6
7
8
9
10
D2
BAV70
SN1
DN1
GN1
DN1
10R
FAN7316
0
VREF
OUTL
GND
ENA
ADIM
BDIM
FB
CMP
OLP2
OLP1
10R
C10
2.7n
0
R5
10k
1
2
2
0
0
D3
BAV70
SN2
OLP3
R6
680
35001WR-02A
DN2
TX2
GN2
C12
33n
OLP1 OLP2
0
REF
R10
12k
R13
100k
R12
75k
C23
N.C.
0
C7 10u
CN3
35001WR-02A
10k
0
R27
10k
C15
3p
0
R29
0
D4
BAV70
OLR
R14
10k
0
R18
100k
0
C16
3p
C18
2.7n
0
R15
10k
2
2
1
2
2
0
OLP1
C19
2.7n
0
C21
4.7n
0
0
1
OLP2
C13
1u
R11
9.1k
C14
0.1u
R20
R23
N.C.
1
DN2
AOP800
0
R22
0R
CN4
0
1
R25
N.C.
R7
680
0
0
R8
R9
100k 100k
2
C11
2.7n
C4 10u
R30
ON/OFF
R4
10k
0
R31
DIM(0~3.3V)
12505WR-10
1
1
2
OLP4
M1
CN5
C9
3p
C8
3p
C6
1u
R24
0R
1
CN1
35001WR-02A
0
0
CN2
35001WR-02A
LTM190EX
TX1
C3
1u
D5
BAV70
R17
680
0
0
R16
680
0
R28
0
C20
1n
C17
10n
0
0
R19
10k
0
20k
R21
20k
Figure 47. Typical Application Circuit
2. Transformer Schematic Diagram
Figure 48. Transformer Schematic Diagram
3. Core & Bobbin
ƒ
ƒ
ƒ
Core: EFD2126
Material: PL7
Bobbin: EFD2126
© 2007 Fairchild Semiconductor Corporation
FAN7316 • 1.0.1
www.fairchildsemi.com
18
FAN7316 — LCD Backlight Inverter Drive IC
Typical Application Circuit (LCD Backlight Inverter)
Pin No.
Wire
Turns
Inductance
Leakage Inductance
Remarks
5Æ2
1 UEW 0.45φ
12
94µH
9.1µH
1kHz, 1V
7Æ9
1 UEW 0.04φ
2560(=0+360•7)
3.88H
420mH
1kHz, 1V
5. BOM of the Application Circuit
Part Ref.
Value
Description
Part Ref.
Value
Description
C5
10nF
50V 1608 K
FUSE
C6
1µF
50V 2012 K
C7
10µF
16V 3216
1608 F
C10
2.7nF
50V 1608 K
Fuse
F1
24V 3A
Resistor (SMD)
R1
30k
R2
100k
1608 J
C11
2.7nF
50V 1608 K
R3
100k
1608 J
C12
33nF
50V 1608 K
R4
10k
1608 F
C13
1µF
50V 3216 K
R5
10k
1608 F
C14
10nF
50V 1608 K
R6
680
1608 F
C17
10nF
50V 1608 K
R7
680
1608 F
C18
2.7nF
50V 1608 K
R8
100k
1608 J
C19
2.7nF
50V 1608 K
R9
100k
1608 J
C20
1nF
50V 1608 K
R10
12k
1608 F
C21
4.7nF
50V 1608 K
R11
9.1k
1608 F
C23
NC
R12
75k
1608 F
R13
100k
1608 J
C8
3p
R14
10k
1608 F
C9
3p
3KV
R15
10k
1608 F
C15
3p
3KV
R16
680
1608 F
C16
3p
3KV
D2
BAV70
Capacitor (DIP)
3KV
R17
680
1608 F
R18
100k
1608 F
R19
10k
1608 F
D3
BAV70
Fairchild Semiconductor
R20
10k
1608 J
D4
BAV70
Fairchild Semiconductor
R21
20k
1608 F
D5
BAV70
Fairchild Semiconductor
R22
0
R23
NC
R24
0
R25
NC
Diode (SMD)
Electrolytic capacitor
C1
330µ
25V
MOSFET (SMD)
M1
AOP800
35001WR-02A
R27
10k
1608 F
R28
20k
1608 F
CN1
0
CN2
35001WR-02A
R30
10
1608 J
CN3
35001WR-02A
10
1608 J
CN4
35001WR-02A
CN5
12505WR-10
Capacitor (SMD)
C2
Alpha & Omega
Wafer (SMD)
R29
R31
Fairchild Semiconductor
1µF
50V 3216 K
C3
1µF
50V 3216 K
TX1
EFD2126
C4
10µF
16V 3216
TX2
EFD2126
© 2007 Fairchild Semiconductor Corporation
FAN7316 • 1.0.1
Transformer (DIP)
www.fairchildsemi.com
19
FAN7316 — LCD Backlight Inverter Drive IC
4. Winding Specification
13.00
12.60
A
11.43
20
11
B
9.50
10.65 7.60
10.00 7.40
2.25
1
PIN ONE
INDICATOR
0.51
0.35
1.27
0.25
M
10
0.65
1.27
C B A
LAND PATTERN RECOMMENDATION
2.65 MAX
SEE DETAIL A
0.33
0.20
C
0.75
0.25
0.10 C
0.30
0.10
X 45°
SEATING PLANE
NOTES: UNLESS OTHERWISE SPECIFIED
(R0.10)
A) THIS PACKAGE CONFORMS TO JEDEC
MS-013, VARIATION AC, ISSUE E
B) ALL DIMENSIONS ARE IN MILLIMETERS.
C) DIMENSIONS DO NOT INCLUDE MOLD
FLASH OR BURRS.
D) CONFORMS TO ASME Y14.5M-1994
GAGE PLANE
(R0.10)
0.25
8°
0°
1.27
0.40
SEATING PLANE
(1.40)
DETAIL A
E) LANDPATTERN STANDARD: SOIC127P1030X265-20L
F) DRAWING FILENAME: MKT-M20BREV3
SCALE: 2:1
Figure 49. 20-SOIC Package
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/
© 2007 Fairchild Semiconductor Corporation
FAN7316 • 1.0.1
www.fairchildsemi.com
20
FAN7316 — LCD Backlight Inverter Drive IC
Physical Dimensions
FAN7316 — LCD Backlight Inverter Drive IC
© 2007 Fairchild Semiconductor Corporation
FAN7316 • 1.0.1
www.fairchildsemi.com
21
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