2006 Fairchild Semiconductor Corporation
1
www.fairchildsemi.com
March 2006
FAN7314 Rev. 1.0.1
F
AN7314 LCD Bac
klight In
ver
ter Drive IC
FAN7314
LCD Backlight Inverter Drive IC
Features
High-efficiency single-stage power conversion
Wide input voltage range: 5V to 25.5V
Back light lamp ballast and soft dimming
Reduces number of required external components
Precision voltage reference trimmed to 2%
ZVS half-bridge topology
Soft start
PWM control at fixed frequency
Analog and burst dimming function
Programmable striking frequency
Open lamp protection
Open lamp regulation
20-Pin SOIC
Description
The FAN7314 provides all the control functions for use
as a series parallel resonant converter as well as a pulse
width modulation (PWM) controller to develop a supply
voltage. Typical operating frequency range is between
30kHz and 250kHz, depending on the CCFL and the
transformer's characteristics.
Ordering Information
Product number
Package
Operating Temperature
FAN7314M
20-SOIC
-25C to 85C
FAN7314MX
FPSTM is a trademark of Fairchild Semiconductor Corporation.
2
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FAN7314 Rev. 1.0.1
F
AN7314 LCD Bac
klight In
ver
ter Drive IC
Internal Block Diagram
BDIM
S_S
EA_OUT
Oscillator
RT
Error Amp.
EA_IN
6
A
+
CT
max. 2V
min. 0.5V
ADIM
OUTB
OUTA
OUTC
OUTD
VIN
2.5VREF
ENA
UVLO 5V
UVLO
REF
BCT
+
max. 2V
min. 0.5V
OLR
+
2V
1.4V
Solr
Q
Q
SET
CLR
S
R
UVLO
OLP
+
+
+
PGND
Sburst
Voltage
Reference
&
Internal Bias
VIN
1.4
A
UVLO
Output
Driver
Output
Control
Logic
AGND
Solr 105
A
Sburst 85
A
Output
Driver
+
+
2.5V
2.65V
Va+
RT1
M
RT1
Striking
Logic
OLP
S_S
V
OLP
V
OLP
+
2.5V 1.5V
3
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FAN7314 Rev. 1.0.1
F
AN7314 LCD Bac
klight In
ver
ter Drive IC
Pin Assignments
Pin Definitions
Pin Number
Pin Name
Pin Function Description
1
OLP
Open Lamp Protection
2
OLR
Open Lamp Regulation
3
ENA
Enable Input
4
S_S
Soft Start
5
GND
Analog Ground
6
REF
2.5V Reference Voltage
7
ADIM
Analog Dimming Input
8
BDIM
Burst Dimming Input
9
EA_IN
Error Amplifier Input
10
EA_OUT
Error Amplifier Output
11
BCT
Burst Dimming Timing Capacitor
12
RT
Timing Resistor
13
CT
Timing Capacitor
14
OUTD
NMOSFET Drive Output D
15
OUTC
PMOSFET Drive Output C
16
PGND
Power Ground
17
VIN
Supply Voltage
18
OUTA
PMOSFET Drive Output A
19
OUTB
NMOSFET Drive Output B
20
RT1
Striking Frequency Resistor
FAN7314
20
19
18
17
16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
OLP
OLR
ENA
S_S
OUTC
REF
ADIM
BDIM
EA_IN EA_OUT
RT1
OUTB
OUTA
VIN
PGND
OUTD
CT
RT
BCT
GND
4
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FAN7314 Rev. 1.0.1
F
AN7314 LCD Bac
klight In
ver
ter Drive IC
Absolute Maximum Ratings
For typical values T
A
= 25
C, V
CC
= 12V and for min/max values T
A
is the operating ambient temperature range with
25
C
T
A
85
C and 5V
V
CC
25.5V, unless otherwise specified.
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.
ESD Level
Electrical Characteristics
For typical values T
A
= 25
C, V
CC
= 12V and for min/max values T
A
is the operating ambient temperature range with
25
C
T
A
85
C and 5V
V
CC
25.5V, unless otherwise specified.
Symbol
Parameter
Value
Unit
V
CC
Supply Voltage
5 to 25.5
V
Topr
Operating Temperature Range
-25 to 85
C
Tj
Junction Temperature
150
C
Tstg
Storage Temperature Range
-65 to 150
C
R
JA
Thermal Resistance Junction-Air
(1, 2)
70
C/W
Pd
Power Dissipation
1.8
W
Parameter
Pins
Conditions
Level
Unit
Human Body Model (HBM)
All pins
R = 1.5k
, C = 100pF
2000
V
Machine Model (MM)
All pins except for BDIM
C = 200pF
300
BDIM
250
Symbol
Characteristics
Test Condition
Min.
Typ.
Max.
Unit
REFERENCE SECTION (Recommend X7R Capacitor)
Vref
Line Regulation
5
V
CC
25.5V
2
25
mV
V25
2.5V Regulation Voltage
2.45
2.5
2.55
V
OSCILLATOR SECTION (Main)
fosc
Oscillation Frequency
T
A
= 25
C, Ct = 270pF
Rt = 18k
110.4
115
119.6
kHz
Ct = 270pF, Rt = 18k
108
115
122
Vcth
CT High Voltage
2.0
V
Vctl
CT Low Voltage
0.5
V
OSCILLATOR SECTION (Burst)
foscb
Oscillation Frequency
T
A
= 25
C, Ctb = 10nF,
Rt = 18k
204.75
225
245.25
Hz
Ctb = 10nF, Rt = 18k
201
225
248
Vbcth
BCT High Voltage
2
V
Vbctl
BCT Low Voltage
0.5
V
5
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FAN7314 Rev. 1.0.1
F
AN7314 LCD Bac
klight In
ver
ter Drive IC
ERROR AMP SECTION
Open Loop Gain
(1)
80
dB
Unit Gain Bandwidth
(1)
1.5
MHz
Veh
Feedback Output High Voltage
EA_IN = 0V
2.13
2.4
2.57
V
lsin
Output Sink Current
EA_OUT = 1.5V
-1
mA
lsur
Output Source Current
EA_OUT = 1.5V
1
mA
Iolr
EA_IN Driving Current On OLR
75
105
135
A
Iburst
EA_IN Driving Current On Burst
Dimming
61
85
109
A
Vfbh
Feedback High Voltage On Burst
Dimming
R(EA_IN) = 60k
Va
+
0.1
Va
+
0.4
Va
+
0.7
V
SOFT START SECTION
I
SS
Soft Start Current
S_S = 2V
4
6
8
A
Vssh
Soft Start Clamping Voltage
2.3
2.65
3
V
PROTECTION SECTION
Volp0
Open Lamp Protection Voltage 0
Start at open lamp
2.2
2.5
2.8
V
Volp1
Open Lamp Protection Voltage 1
Normal
open lamp
1.3
1.5
1.7
V
Volr
Open Lamp Regulation Voltage
1.75
2
2.25
V
Iolp
Open Lamp Protection Charging
Current
0.7
1.4
2.1
A
UNDER VOLTAGE LOCK OUT SECTION
Vth
Start Threshold Voltage
5
V
Ist
Start Up Current
V
CC
= Vth0.2
130
180
A
Iop
Operating Supply Current
V
CC
= 12V
1.5
4
mA
Isb
Stand-by Current
V
CC
= 12V
200
370
A
ON/OFF SECTION
Von
On State Input Voltage
2
5
V
Voff
Off Stage Input Voltage
0.7
V
OUTPUT SECTION
Vpdhv
PMOS Gate High Voltage
V
CC
= 12V
Vcc
V
Vphlv
PMOS Gate Low Voltage
V
CC
= 12V
Vcc10.5 Vcc8.5
Vcc6.5
V
Vndhv
NMOS Gate Drive Voltage
V
CC
= 12V
6.5
8.5
10.5
V
Vndhv
NMOS Gate Drive Voltage
V
CC
= 12V
0
V
Vpuv
PMOS Gate Voltage With UVLO
Activated
V
CC
= Vth0.2
Vcc0.3
V
Vnuv
NMOS Gate Voltage With UVLO
Activated
V
CC
= Vth0.2
0.3
V
Tr
Rising Time
(1)
V
CC
= 12V, Cload = 2nF
200
500
ns
Tf
Falling Time
(1)
V
CC
= 12V, Cload = 2nF
200
500
ns
Symbol
Characteristics
Test Condition
Min.
Typ.
Max.
Unit
Electrical Characteristics
(Continued)
For typical values T
A
= 25
C, V
CC
= 12V and for min/max values T
A
is the operating ambient temperature range with
25
C
T
A
85
C and 5V
V
CC
25.5V, unless otherwise specified.
6
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FAN7314 Rev. 1.0.1
F
AN7314 LCD Bac
klight In
ver
ter Drive IC
Notes:
1. These parameters, although guranteed, are not 100% tesed in production.
2. Specifications to -25C to 85C are guaranteed by design based on final characterization results.
MAX./MIN. OVERLAP
Min. Overlap Between Diagonal
Switches
(1)
fosc = 100kHz
0
%
Max. Overlap Between Diagonal
Switches
(1)
fosc = 100kHz
100
%
DELAY TIME
PDR_A/NDR_B
(1)
Rt = 18k
450
ns
PDR_C/NDR_D
(1)
Rt = 18k
450
ns
Symbol
Characteristics
Test Condition
Min.
Typ.
Max.
Unit
7
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FAN7314 Rev. 1.0.1
F
AN7314 LCD Bac
klight In
ver
ter Drive IC
Function Description
UVLO: The under voltage lockout circuit guarantees
stable operation of the IC's control circuit by stopping
and starting operation as a function of the Vin value. The
UVLO circuit turns on the control circuit when Vin
exceeds 5V. When Vin is lower than 5V, the IC's standby
current is less than 200A.
ENA:
Applying voltage higher than 2V to the ENA pin
enables the operation of the IC. Applying voltage lower
than 0.7V to the ENA pin will disable the operation of the
inverter.
Soft start: The soft start function requires that the S_S
pin is connected through a capacitor to GND. A soft start
circuit ensures a gradual increase in the input and output
power. The capacitor value connected to the S_S pin
determines the rate at which the duty ratio rises. It is
charged by a 6A current source.
Main oscillator: The timing capacitors (CTs) are
charged by the reference current source. The current
source is formed by the timing resistor (R
T
). The timing
resistor's voltage is regulated at 1.25V. The sawtooth
waveform (see top of next column) charges up to 2V.
Once this voltage is reached, the capacitors begin dis-
charging down to 0.5V. Next, the timing capacitors start
charging again and a new switching cycle begins. The
main frequency can be programmed by adjusting the R
T
and C
T
values. The main frequency can be calculated as
shown below:
Burst oscillator & burst dimming: The timing capaci-
tors (BCTs) are charged by the reference current source,
which is formed by the timing resistor (R
T
). The timing
resistor's voltage is regulated at 1.25V. The sawtooth
waveform charges up to 2V. Once this voltage is
reached, the capacitors begin discharging down to 0.5V.
Next the timing capacitors start charging again and a
new switching cycle begins. The burst dimming fre-
quency can be programmed by adjusting the R
T
and
BC
T
values. The burst dimming frequency can be calcu-
lated as shown below:
To avoid visible flicker, the burst dimming frequency
should be greater than 120Hz.
By comparing the input of BDIM pin with the 0.5 to 2V
triangular wave of the burst oscillator, the PWM pulses
for burst dimming. The PWM pulse controls EA_OUT's
voltage by summing 85A into the EA_IN pin.
f
op =
19
32 R
T
C
T
-------------------------------
f
burst
=
3.75
96 R
T
BC
T
-----------------------------------
8
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FAN7314 Rev. 1.0.1
F
AN7314 LCD Bac
klight In
ver
ter Drive IC
Open lamp regulation & open lamp protection: It is
necessary to suspend power stage operation if an open
lamp occurs, because the power stage has high gain.
When a voltage higher than 2V is applied to the OLR pin,
the part enters regulation mode and controls the
EA_OUT voltage. This limits the lamp voltage by sum-
ming 105A into the feedback node. At the same time,
the OLP capacitor, connected to the OLP pin, is charged
by the 1.4A internal current source. Once it reaches
2.5V, the IC enters shut down where all the output is
high.
Output Drives: The four output drives are designed so
that switches A and B, C and D never turn on simulta-
neously. The OUTA-OUTB pair is intended to drive one
half-bridge in the external power stage. The OUTC-
OUTD pair will drive the other half-bridge.
9
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FAN7314 Rev. 1.0.1
F
AN7314 LCD Bac
klight In
ver
ter Drive IC
Timing Diagram
The FAN7314 uses the half-bridge to drive CCFL.
CT
SYNC
POUT A
NOUT B
POUT C
NOUT D
EA_OUT
T
10
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FAN7314 Rev. 1.0.1
F
AN7314 LCD Bac
klight In
ver
ter Drive IC
Typical Application Circuit
1. Schematic
2. Transformer Schematic Diagram
Supported by Namyang electronics (http://www.namyangelec.co.kr)
3. Core & Bobbin
Core: EFD2124
Material: PL7
Bobbin: EFE2124
Application
Lamps
Input Voltage
19 inch LCD Monitor
4
13V
0
OLP1
R17
1k
D3
BAV70
R16
1k
0
0
C11
15p
0
C30
10n
0
0
C2 1u
TX1
0
0
C21
10n
R6 82k
C8 10u
C25
1u
0
0
0
0
C28
10n
D9
BAV99
D7
BAV99
D6
BAV99
0
0
R9
9.1k
0
HOT
1
COLD
2
CN1
CCFL
HOT
1
COLD
2
CN2
CCFL
HOT
1
COLD
2
CN4
CCFL
HOT
1
COLD
2
CN3
CCFL
C22
22 0u
25V
OLR
C26 0.1u
0
J1
0
RT
OLP
D10
BAW56
REF
R14
100k
OUTB
D1
BAW56
RT
FB
R1
330k
LTM190EX
SN
GN
SP
GP
DP
DP
DN
DN
M2
FDS8958A
C6
1u
0
OLP2
OLP1
OLP3
OLP4
R12
1k
R11
1k
R26
1k
REF
R13
1k
0
0
0
0
R15
10k
C9
1u
0
F1
FUSE
C7 10u
1
2
3
4
5
6
7
8
9
10
CN5
12505WR-10
R24
10k
R27
10k
R25
10k
OUTA
C10
15p
C14
10n
C12
15p
C29
10n
IC1
FAN7314
S_S
GND
REF
OLR
ENA
BDIM
OLP
VIN
OUTA
PGND
OUTB
RT1
CT
OUTC
ADIM
EA_IN
EA_OUT
OUTD
RT
BCT
R22
10k
R23
10k
C19
2.2n
C20
2.2n
0
0
0
0
R21
10k
R20
10k
C18
2.2n
C17
2.2n
0
0
R7 0
R8
100k
Q1
KST2222
0
C15
10n
C27
1u
0
0
R18
1k
0
SN
GN
SP
GP
DP
DP
DN
DN
M1
FDS8958A
0
TX2
FB
0
C13
15p
0
OLP3
OLP4
D11
BAW56
0
R19
1k
0
OLR
ON/OFF
13V
DIM (0~3.3V )
0
C4
4.7n
C5 220p
R5 27k
0
R2
56k
R3
18k
R4
22k
0
0
C3
4.7n
D4
BAV70
C1 0.22u
D8
BAV99
0
OLP2
0
OLR
FB
1
1
6
9
7
2
3
4
5
6
7
8
9
11
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FAN7314 Rev. 1.0.1
F
AN7314 LCD Bac
klight In
ver
ter Drive IC
4. Winding Specification
5. BOM of the Application Circuit
Pin No.
Wire
Turns
Inductance
Leakage Inductance
Remarks
5
2
1 UEW 0.45
12
180H
7.2H
1KHz, 1V
7
9
1 UEW 0.04
2430 (270 x 9)
7.2H
330mH
1KHz, 1V
Part Ref.
Value
Description/Vendor
Part Ref.
Value
Description/Vendor
Fuse
C5
220p
50V 1608 J
F1
24V 3A
Fuse
C6
1
50V 2012 K
Resistor (SMD)
C7
10
16V 3216
R1
330K
1608 J
C8
10
16V 3216
R2
56K
1608 F
C9
1
16V 1608 K
R3
18K
1608 F
C10
15p
3KV 3216
R4
22K
1608 F
C11
15p
3KV 3216
R5
27K
1608 F
C12
15p
3KV 3216
R6
82K
1608 F
C13
15p
3KV 3216
R8
100K
1608 F
C14
10n
50V 1608 K
R9
9.1K
1608 F
C15
10n
50V 1608 K
R11
1K
1608 F
C17
2.2n
50V 1608 Z
R12
1K
1608 F
C18
2.2n
50V 1608 Z
R13
1K
1608 F
C19
2.2n
50V 1608 Z
R14
100K
1608 F
C20
2.2n
50V 1608 Z
R15
10K
1608 F
C21
10n
50V 1608 Z
R16
1K
1608 F
C25
1
50V 2012 K
R17
1K
1608 F
C26
0.1
16V 1608 K
R18
1K
1608 F
C27
1
50V 2012 K
R19
1K
1608 F
C28
10n
50V 1608 Z
R20
10K
1608 J
C29
10n
50V 1608 K
R21
10K
1608 J
C30
10n
50V 1608 K
R22
10K
1608 J
Diode / TR (SMD)
R23
10K
1608 J
D1
BAW56
Fairchildsemi
R24
10K
1608 J
D3
BAV70
Fairchildsemi
R25
10K
1608 J
D4
BAV70
Fairchildsemi
R26
1K
1608 F
D6
BAV99
Fairchildsemi
R27
10K
1608 J
D7
BAV99
Fairchildsemi
Capacitor (SMD)
D8
BAV99
Fairchildsemi
C1
0.22
16V 1608 K
D9
BAV99
Fairchildsemi
C2
1
50V 2012 K
D10
BAW56
Fairchildsemi
C3
4.7n
50V 1608 K
D11
BAW56
Fairchildsemi
C4
4.7n
50V 1608 K
Q1
KST2222
Fairchildsemi
12
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FAN7314 Rev. 1.0.1
F
AN7314 LCD Bac
klight In
ver
ter Drive IC
5. BOM of the Application Circuit
(Continued)
Part Ref.
Value
Description/Vendor
Part Ref.
Value
Description/Vendor
Electrolytic capacitor
Wafer (SMD)
C22
220
25V
CN1
35001WR-02A
MOSFET (SMD)
CN2
35001WR-02A
M1
FDS8958A
Fairchildsemi
CN3
35001WR-02A
M2
FDS8958A
Fairchildsemi
CN4
35001WR-02A
Transformer (SMD)
CN5
12505WR-10
TX1
EFD2124
Supported by Namyang electronics
(http://www.namyangelec.co.kr)
TX2
EFD2124
13
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FAN7314 Rev. 1.0.1
F
AN7314 LCD Bac
klight In
ver
ter Drive IC
Mechanical Dimensions
20-pin SOIC Package
A
.093
.104
2.35
2.65
Symbol
Inches
Min.
Max.
Min.
Max.
Millimeters
Notes
A1
.004
.012
0.10
0.30
.020
0.51
B
.013
0.33
C
.009
.013
0.23
0.32
E
.291
.299
7.40
7.60
e
.394
.419
10.00
10.65
.010
.029
0.25
0.75
H
.050 BSC
1.27 BSC
h
L
.016
.050
0.40
1.27
0
8
0
8
3
6
5
2
2
N
20
20
ccc
.004
0.10
--
--
D
.496
.512
12.60
13.00
Notes:
1.
2.
3.
4.
5.
6.
Dimensioning and tolerancing per ANSI Y14.5M-1982.
"D" and "E" do not include mold flash. Mold flash or
protrusions shall not exceed .010 inch (0.25mm).
"L" is the length of terminal for soldering to a substrate.
Terminal numbers are shown for reference only.
"C" dimension does not include solder finish thickness.
Symbol "N" is the maximum number of terminals.
20
1
D
A
A1
C
ccc C
LEAD COPLANARITY
SEATING
PLANE
e
B
L
h x 45
C
11
10
E
H
14
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FAN7314 Rev. 1.0.1
F
AN7314 LCD Bac
klight In
ver
ter Drive IC
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.
TRADEMARKS
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.
LIFE SUPPORT POLICY
FAIRCHILDS 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
Preliminary
No Identification Needed
Obsolete
This datasheet contains the design specifications for
product development. Specifications may change in
any manner without notice.
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.
This datasheet contains final specifications. Fairchild
Semiconductor reserves the right to make changes at
any time without notice in order to improve design.
This datasheet contains specifications on a product
that has been discontinued by Fairchild semiconductor.
The datasheet is printed for reference information only.
Formative or
In Design
First Production
Full Production
Not In Production
ISOPLANARTM
LittleFETTM
MICROCOUPLERTM
MicroFETTM
MicroPakTM
MICROWIRETM
MSXTM
MSXProTM
OCXTM
OCXProTM
OPTOLOGIC
OPTOPLANARTM
PACMANTM
POPTM
Power247TM
PowerEdgeTM
FAST
FASTrTM
FPSTM
FRFETTM
GlobalOptoisolatorTM
GTOTM
HiSeCTM
I
2
CTM
i-LoTM
ImpliedDisconnectTM
IntelliMAXTM
Rev. I18
ACExTM
ActiveArrayTM
BottomlessTM
Build it NowTM
CoolFETTM
CROSSVOLTTM
DOMETM
EcoSPARKTM
E
2
CMOSTM
EnSignaTM
FACTTM
FACT Quiet SeriesTM
PowerSaverTM
PowerTrench
QFET
QSTM
QT OptoelectronicsTM
Quiet SeriesTM
RapidConfigureTM
RapidConnectTM
SerDesTM
ScalarPumpTM
SILENT SWITCHER
SMART STARTTM
SPMTM
StealthTM
SuperFETTM
SuperSOTTM-3
SuperSOTTM-6
SuperSOTTM-8
SyncFETTM
TCMTM
TinyLogic
TINYOPTOTM
TruTranslationTM
UHCTM
UltraFET
UniFETTM
VCXTM
WireTM
Across the board. Around the world.TM
The Power Franchise
Programmable Active DroopTM
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