Power_Management_For_LEDs.pdf

VOL 2
Power Management for LEDs
High Performance Analog ICs
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LEDs and LED Driver Technology
LEDs
A light-emitting diode (LED) is a semiconductor device that emits narrow-spectrum incoherent light when forward-biased.
The color of the emitted light depends on the chemical composition of the semiconductor material used, and can be
near-ultraviolet, visible or infrared. LEDs are more prevalent today than ever before, replacing traditional incandescent and
fluorescent bulbs in many lighting applications. Incandescents use a heated filament, are subject to breakage and burnout and operate at a luminous efficiency of 2% to 4%. Fluorescents are more efficient, at 7% to 12%, but require high
drive voltage and contain mercury, a toxic substance that may be eventually banned in certain countries. LEDs, however,
produce light directly through electroluminescence, operate at low voltage and can deliver over 20% luminous efficiency.
Key Advantages of LEDs and Their Operation Versus Alternative Lighting Sources
. High energy efficiency: LEDs are 7x to 10x more efficient at producing light (lumens) than incandescent bulbs
. Extremely long life span: Typically 100,000 hours for LEDs versus 1,000 hours for incandescent bulbs and
10,000 hours for fluorescent bulbs
. Solid state reliability
. Nearly indestructible, solid epoxy lens cases – insensitive to vibration and shocks
. Fast “turn-on” time – light up very quickly
. Compact size
. Capable of emitting light of an intended color without the use of color filters
. Focused light output – incandescent and fluorescent sources often require an external reflector to collect light
and direct it in a useable manner
. Gradual reduction of light output over time, rather than sudden burn-out of incandescent bulbs
LEDs deliver high efficiency, a key advantage in lighting systems. Incandescent bulbs generate significant heat as part
of the light-production process. This is inefficient energy use since over 95% of the energy is not converted into visible
light. On the other hand, LEDs convert a much higher percentage of electrical power into light output, substantially
reducing power consumption.
Key advancements in LED reliability have enabled lifetimes in excess of 100,000 hours. Recently, these have included
alternative semiconductor doping techniques, new optical lens technologies and advanced heat sink and packaging
techniques. Many developments are underway that will increase efficiency and lifetime even further, including improved
case/housing designs, further improvements in light conversion efficiency and more thermally efficient packages for higher
current operation.
LED Driver Technology
LED driver circuits are available in several topologies:
. Inductor-based Buck, Boost, Buck-Boost and SEPIC designs (these generally drive LEDs in series or multiple strings
of LEDs in series):
. LED currents range from a few milliamps to multiple amps
. Efficiencies in excess of 90%
. Drivers act as constant current sources
. Many devices use high side current sense: LED string can be returned to ground
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. Inductorless charge pump-based Buck, Boost, Buck-Boost designs (these generally drive a single LED
or LED strings in parallel):
. LED currents range from a few milliamps to 1A
. Average efficiencies over the Li-Ion battery range in excess of 80%
. Drivers act as constant current sources
. Very small solution footprints – ideal for handheld devices
Deciding which IC and topology to use depends on the following factors:
. The required LED current
. The relation of LED(s) forward voltage to the input voltage range: Buck, Boost, Buck-Boost, SEPIC or Flyback
. Efficiency – crucial for driving high brightness (HB) LEDs while minimizing thermal and battery life constraints
. Current consumption required during off-time
. Dimming characteristics – PWM dimming preserves chromatic characteristics across brightness levels
and avoids color shifting
. Number of LEDs / serial or parallel
. Total solution size and cost constraints
ICs specifically designed as LED drivers tend to be smaller in size compared to general-purpose alternative solutions,
increasing their appeal in space-constrained portable power applications. Popular switchmode LED driver configurations
include Buck, Boost, Buck-Boost and SEPIC, and can deliver current from 3mA/LED to 3A/LED or more.
Choosing the best LED driver or display bias power IC depends on many factors and tradeoffs. Linear Technology
provides targeted solutions for most applications.
Key LED Applications for Semiconductor ICs
. Automotive Lighting – Interior and Exterior
. Portable Electronic Devices
. LCD and CCD Panel Backlights
. Signaling
. Signs and Illumination
. Photo Sensors
. Commercial Lighting
. Residential Lighting
LED Driver Solutions Overview
Linear Technology offers a broad line of LED drivers including both inductor-based (for LEDs in series) and inductorless
(for LEDs in parallel) converters. These are offered in several different topologies, providing the highest efficiency, lowest
noise and smallest footprints. Other features include integrated Schottky diodes, accurate LED current matching, a variety
of dimming options and multiple output capability.
This selection guide features Linear Technology solutions for a wide variety of LED driver applications.
For more information on our latest products, visit our website at www.linear.com.
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page
03
04
05
06
07
08
High Current LED Driver ICs (>350mA)
Switching Regulator-Based (Inductor), LEDs in Series
Buck
Boost
Buck-Boost
SEPIC-Flyback
Photoflash/Camera Torch
Charge Pump-Based (Inductorless), LEDs in Parallel
Single Output – Camera Flash/Torch
Medium Current LED Driver ICs (100-350mA)
09
10
11
12
Switching Regulator-Based (Inductor), LEDs in Series
Buck
Boost
Buck-Boost
Multidisplay
Low Current LED Driver ICs (20mA to 90mA)
12
13
14
17
18
15 –16
Switching Regulator-Based (Inductor), LEDs in Series
Multidisplay
Buck for Large Panel TFT LCDs
Boost
Charge Pump-Based (Inductorless), LEDs in Parallel
Multidisplay
General Purpose
Multichannel LED Drivers for Large LCD Panels (30mA to 50mA)
OLED
19
Switching Regulator Based (Inductor)
LCD & CCD Bias
20
Switching Regulator Based (Inductor)
Series LED Driver ICs
03–07
09–16
19 –20
VIN
8V TO
40V
L1
22µH
C1
4.7µF
1M
D1
187k
SHDN/UVLO
FB
VREF
ISP
16.9k
C2
4.7µF
1M
VIN
23.7k
LT3755
0.1Ω
1A
CTRL
INTVCC
100k
ISN
100k
NTC
RT1
M1
GATE
SENSE
OPENLED
PWM
SS
RT
VC
0.01µF
28.7k
400kHz
0.015Ω
50W
LED
STRING
PWMOUT
GND INTVCC
10k
4.7µF
0.001µF
M2
Parallel LED Driver ICs
08
17–18
2.2µF
2.2µF
C1P C1M C2P C2M
VIN
CPO
LTC3220
2.2µF
LTC3220-1
VIN
DVCC
DVCC
ULED1-18
0.1µF
I2C
RESET
04109 CS3_LIN_LED_FA_10–7–08.r2.indd 5
SCL/SDA
RST
RGB1
RGB2
RGB3
RGB4
MAIN
4.7µF
18
GND
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HIGH CURRENT (350mA TO 10A) LED DRIVERS – BUCK
03
High Current (350mA to 10A) LED Drivers – Buck
High-current inductor-based step-down switching LED drivers
provide tiny, efficient high power LED lighting solutions for
automotive, architectural and display backlighting. Key features
include wide-ranging True Color PWM™ dimming, wide input voltage
range, high side sensing and high switching frequency.
Applications:
. Automotive and Avionic Lighting
. Architectural Detail Lighting
. Display Backlighting
. Constant Current Sources
LT3756: 100V High Voltage Full Featured LED Driver
LT3756: Actual Size,
Complete Solution
Buck Mode 1A LED Driver with High Dimming Ratio and Open LED Reporting
C1
1µF
1M
VIN
365k
ISP
SHDN/UVLO
1.5k
6.19k
VREF
0.17
1A
+
22V
–
Efficiency vs VIN
ISN
FB
CTRL
M2
PWMOUT
5 WHITE LEDs
20W
1k
LT3756
INTVCC
L1
100µH
100k
28.7k
400kHz
GATE
RT
VC
SENSE
GND INTVCC
96
D1
OPENLED
SS
100
22.1k
M3
PWM
0.1µF
C3
4.7µF
100k
EFFICIENCY (%)
VIN
24V TO
80V
VIN
C4
4.7µF
M1
88
0.0437
84
C2
4.7µF
47k
92
0.001µF
80
20
Part
Number
Topology
Dimming
Type
Max #
of LEDs
x ILED from
24VIN
LED
Configuration
Input
Voltage
Range
(V)
Max.
Output
Voltage
(V)
30
40
60
50
VIN (V)
70
80
ISW (A)
Operating
Efficiency
(%)
Package
High Current (350mA to 10A) LED Drivers - Buck
LT3474/-1
Buck
400:1 PWM
4 x 1A
Series
3 to 30
(40VMAX)
15/25
1.5
88
TSSOP-16E
LT3592
Buck
10:1 Analog
4 x 500mA
Series
4 to 36
30
0.8
88
2x2 DFN-10
MSOP-10E
LT3517
Buck
5000:1 PWM
5 x 1A
Series
3 to 30
(40VMAX)
40
1.5
92
4x4 QFN-16
TSSOP-16E
LT3518
Buck
5000:1 PWM
5 x 1.5A
Series
3 to 30
(40VMAX)
40
2.3
92
4x4 QFN-16
TSSOP-16E
LT3496
Triple Buck
3000:1 PWM
3 x 5 x 0.5A
3 x Series Strings
3 to 30
(40VMAX)
40
3 x 0.75
92
4x5 QFN-28
LT3475/-1
Dual Buck
3000:1 PWM
2 x 4 x 1.5A
2 x Series Strings
4 to 36
15/25
2 x 1.5
88
TSSOP-20/E
LT3478/-1
Buck
3000:1 PWM
5 x 1.5A
Series
2.7 to 36
30
4.5
92
TSSOP-16E
LT3476
Quad Buck
1000:1 PWM
4 x 5 x 1A
4 x Series Strings
2.8 to 36
30
4 x 1.5
96
5x7 QFN-38
LTC3783
Buck
3000:1 PWM
5 x 1A +
Series
3 to 36
36
Ext FET
95
4x5 DFN-16
TSSOP-16
LT3755/-1
Buck
3000:1 PWM
5 x 1A +
Series
4.5 to 40
75
Ext FET
96
3x3 QFN-16
MSOP-16E
LT3756
Buck
3000:1 PWM
5 x 1A +
Series
6 to 100
100
Ext FET
96
3x3 QFN-16
MSOP-16E
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04
02
HIGH CURRENT (350mA TO 10A) LED DRIVERS – BOOST
High Current (350mA to 10A) LED Drivers – Boost
Applications:
High current inductor-based step-up switching LED drivers
provide compact, efficient high power LED lighting solutions for
automotive, architectural and display backlighting. Key features
include wide-ranging True Color PWM dimming, wide input
voltage range, high side sensing and high switching frequency.
. Automotive and Avionic Lighting
. Architectural Detail Lighting
. Display Backlighting
. Constant Current Sources
LT3755: Boost Demo
Circuit. Actual Size,
Complete Solution
LT3755: 75V High Voltage Full Featured LED Driver
50W White LED Headlamp Driver
VIN
8V TO
40V
L1
22µH
C1
4.7µF
1M
D1
187k
SHDN/UVLO
FB
VREF
ISP
Efficiency vs Load
23.7k
LT3755
16.9k
C2
4.7µF
1M
VIN
0.17
1A
100
CTRL
INTVCC
100k
VIN = 12V
ISN
100k
NTC
RT1
M1
GATE
96
SENSE
0.01µF
28.7k
400kHz
0.0157
50W
LED
STRING
PWMOUT
GND INTVCC
10k
EFFICIENCY (%)
OPENLED
PWM
SS
RT
VC
92
88
4.7µF
0.001µF
84
M2
80
0.0
Part
Number
Topology
Dimming
Type
Max #
of LEDs
x ILED from
12VIN
LED
Configuration
Input
Voltage
Range
(V)
Max.
Output
Voltage
(V)
0.2
0.4
0.6
LOAD (A)
0.8
1.0
ISW (A)*
Operating
Efficiency
(%)
Package
High Current (350mA to 10A) LED Drivers – Boost
LT3486
Dual Boost
1000:1 PWM
2 x 5 x 350mA
2x Series Strings
2.7 to 24
35
2 x 1.3
85
3x5 DFN-16
LT3517
Boost
5000:1 PWM
8 x 350mA
Series
3 to 30
(40VMAX)
45
1.5
87
4x4 QFN-16
TSSOP-16E
LT1618
Boost
Analog/PWM
6 x 350mA
Series
1.6 to 18
36
1.5
85
3x3 DFN-10
MSOP-10
LT3518
Boost
5000:1 PWM
11 x 350mA
Series
3 to 30
(40VMAX)
45
2.3
87
4x4 QFN-16
TSSOP-16E
LT3496
Triple Boost
3000:1 PWM
3 x 4 x 350mA
3 x Series Strings
3 to 30
(40VMAX)
45
3 x 0.75
87
4x5 QFN-28
LT3478/-1
Boost
3000:1 PWM
10 x 700mA
Series
2.7 to 36
40
4.5
87
TSSOP-16E
LT3476
Quad Boost
1000:1 PWM
4 x 8 x 350mA
4 x Series Strings
2.8 to 16
36
4 x 1.5
87
5x7 QFN-38
LTC3783
Boost
3000:1 PWM
10:1 Analog
10 x 1A
Series
3 to 36+
36
Ext FET
93
4x5 DFN-16
TSSOP-16
LT3755/-1
Boost
3000:1 PWM
15 x 1A
Series
4.5 to 40
75
Ext FET
93
3x3 QFN-16
MSOP-16E
LT3756
Boost
3000:1 PWM
25 x 0.5A
Series
6 to 100
100
Ext FET
93
3x3 QFN-16
MSOP-16E
* IOUT ~ 0.65 ISW x (VIN / VOUT). Estimate: may vary depending on external component selection.
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HIGH CURRENT (350mA TO 10A) LED DRIVERS – BUCK-BOOST
05
03
High Current (350mA to 10A) LED Drivers – Buck-Boost
Applications:
High current inductor-based buck-boost switching LED drivers
provide flexible, tiny, efficient solutions for TFT backlighting,
automotive and avionic lighting applications. Key features include
high current, high voltage switches, adjustable LED currents, wide
input voltage range, and high switching frequency.
. RGGB Lighting
. Automotive and Avionic Lighting
. TFT LCD Backlighting
. Constant-Current Sources
LT3476: High Current Quad Output LED Driver
LT3476: Actual Size,
Complete Solution
5V to 25V Step-Up/Step-Down Driver for 2 Series 350 mA LEDs
PVIN
5V TO 25V
350mA
350mA
350mA
10µH
10µH
LED1
10µH
10µH
LED2
LED3
CAP2
CAP1
2.2µF
PWM1-4
SHDN
2.2µF
LED4
300m7
300m7
300m7
VIN
2.8V TO
16V
350mA
300m7
CAP3
2.2µF
SW1
CAP1-4
LED1-4
VIN
PWM1-4
SHDN
CAP4
2.2µF
SW2
SW3
LT3476
GND
1000:1 PWM Dimming at 100Hz
2.2µF
SW4
REF
VADJ1-4
PWM
5V/DIV
1.05V
VC1-4
RT
47k
47nF
ILED
500mA/
DIV
5µs/DIV
Part
Number
Topology
Dimming
Type
Max #
of LEDs
x ILED from
12VIN
LED
Configuration
Input
Voltage
Range
(V)
Max.
Output
Voltage
(V)
ISW (A)
Operating
Efficiency
(%)
Package
High Current (350mA to 10A) LED Drivers – Buck-Boost
LT3517
Buck-Boost
5000:1 PWM
6 x 350mA
Series
3 to 30
(40VMAX)
45
1.5
80
4x4 QFN-16
TSSOP-16E
LT3518
Buck-Boost
5000:1 PWM
6 x 500mA
Series
3 to 30
(40VMAX)
45
2.3
80
4x4 QFN-16
TSSOP-16E
LT3496
Triple Buck-Boost
3000:1 PWM
3 x 350mA
Series
3 to 30
(40VMAX)
45
3 x 0.75
80
4x5 QFN-28
LT3478/-1
Buck-Boost
3000:1 PWM
5 x 700mA
Series
2.7 to 36
40
4.5
80
TSSOP-16E
LT3476
Quad Buck-Boost 1000:1 PWM
4x5x
350mA
4 x Series
Strings
2.8 to 16
36
4 x 1.5
80
5x7 QFN-38
LTC3783
Buck-Boost
3000:1 PWM
10:1 Analog
6 x 1A
Series
3 to 36+
36
Ext FET
85
4x5 DFN-16
TSSOP-16
LT3755/-1
Buck-Boost
3000:1 PWM
10 x 1A
Series
4.5 to 40
75
Ext FET
85
3x3 QFN-16
MSOP-16E
LT3756
Buck-Boost
3000:1 PWM
15 x 1A
Series
6 to 100
100
Ext FET
85
3x3 QFN-16
MSOP-16E
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06
02
H I G H C U R R E N T ( 3 5 0 m A T O 1 0 A ) L E D D R I V E R S – S E P I C A N D F LY B A C K
High Current (350mA to 10A) LED Drivers – SEPIC and Flyback
High current inductor-based multitopology switching LED drivers
provide flexible solutions for high voltage LED arrays. Key features
include high current, wide input voltage range, scaleable output
voltage, and wide-ranging True Color dimming.
Applications:
. High Power LED Applications
. Industrial
. Automotive
LT3755: SEPIC Demo
Circuit. Actual Size,
Complete Solution
LT3755: 75V High Voltage Full Featured LED Driver
20W SEPIC LED Driver
VIN
8V TO
40V
C4
1µF
100V
L1A
22µH
C1
4.7µF
50V
1M
VIN
C3
4.7µF
50V
511k
SHDN/UVLO
FB
SEPIC Efficiency vs VIN
L1B
VREF
187k
D1
5A
100V
25k
100
VOUT = 18V
ILED = 1A
LT3755
ISP
CTRL
INTVCC
0.17
100k
1A
95
M1
GATE
OPENLED
PWM
SENSE
SS
RT
PWMOUT
VC
GND INTVCC
0.01µF
28.7k
400kHz
30k
EFFICIENCY (%)
ISN
20W
LED
STRING
0.0157
90
85
C2
4.7µF
10V
0.001µF
M2
80
0
Part
Number
Topology
Dimming
Type
Max #
of LEDs
x ILED from
12 VIN
LED
Configuration
10
20
VIN (V)
Input
Voltage
Range
(V)
Max.
Output
Voltage
(V)
ISW (A)
Operating
Efficiency
(%)
40
30
Package
High Current (350mA to 10A) LED Drivers – SEPIC and Flyback
LT3517
SEPIC/FlyBack
5000:1
PWM
4 x 350mA
Series
3 to 30
(40VMAX)
45*
1.5
80
4x4 QFN-16
TSSOP-16E
LT3518
SEPIC/FlyBack
5000:1
PWM
6 x 350mA
Series
3 to 30
(40VMAX)
45*
2.3
80
4x4 QFN-16
TSSOP-16E
LT3478/-1
SEPIC/FlyBack
3000:1
PWM
6 x 500mA
Series
2.7 to 36
40*
4.5
80
TSSOP-16E
LT3476
Quad SEPIC/
FlyBack
1000:1
PWM
4x3x
350mA
4 x Series
Strings
2.8 to 16
36*
4 x 1.5
80
5x7 QFN-38
LTC3783
SEPIC/FlyBack
3000:1
PWM 10:1
Analog
6 x 1A
Series
3 to 36+
Limited
by ext.
FET
Ext FET
85
4x5 DFN-16
TSSOP-16
LT3755/-1
SEPIC/FlyBack
3000:1
PWM
6 x 1A
Series
4.5 to 40
75
Ext FET
85
3x3 QFN-16
MSOP-16E
LT3756
SEPIC/FlyBack
3000:1
PWM
8 x 1A
Series
6 to 100
100
Ext FET
90
3x3 QFN-16
MSOP-16E
* VIN + VOUT
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MEDIUM TO HIGH CURRENT (100mA TO 2A) LED DRIVERS FOR PHOTOFLASH/TORCH LIGHTING
07
03
Medium to High Current (100mA to 1A) LED Drivers for Photoflash/Torch Lighting
LED Power Efficiency vs VIN
High current inductor-based switching LED drivers for camera
photoflash, torch and video lighting feature various topologies
including buck-boost and boost and provide tiny, efficient high
power solutions for camera phone applications.
100
ILED = 150mA
95
90
EFFICIENCY (%)
Applications:
. Cell Phone Camera Flash
. Cell Phone Torch Lighting
. Digital Cameras
. PDAs
. Miscellaneous Li-Ion/Polymer-Based LED Driver Applications
85
ILED = 1A
80
75
70
65 TA = 25°C
EFFICIENCY = (VOUT – VLED)ILED/VINIIN
60
2.7 3.1 3.5 3.9 4.3 4.7
VIN (V)
5.1
5.5
LTC3454: 1A Synchronous Buck-Boost High Current LED Driver
VIN
1-CELL
Li-ion
2.7V - 4.2V
L1
5μH
10μF
10μF
VIN
SW1
SW2
ILED
LTC3454: Actual Size,
Complete Solution
VOUT
LED
EN2
0
0
1
1
LED
LTC3454
EN1 (TORCH)
EN1
0
1
0
1
ILED
0 (SHUTDOWN)
150mA
850mA
1A
EN2 (FLASH)
VC
0.1μF
Part
Number
ISET1
ISET2
GND (EXPOSED PAD)
Topology
VIN (V)
VOUT (V)*
Max.
Total LED
Current
(mA)*
RISET2
3.65k
1%
RISET1
20.5k
1%
Max. No.
of White
LEDs
Dimming
Control
Frequency
(MHz)
IQ
(mA)
ISD
(µA)
Package
Medium to High Current (100mA to 1A) LED Drivers for PhotoFlash/Torch Lighting
LTC3452
Buck-Boost
2.7 to 5.5
4.5
200
4
DC/PWM
1
0.6
<1
4x4 QFN-20
LTC3490
Boost
1.0 to 3.2
4
350
1
DC/PWM
1.3
1
<50
3x3 DFN-8
SO-8
LTC3453
Buck-Boost
2.7 to 5.5
4.5
500
1
DC/PWM
1
2.5
<6
4x4 QFN-16
LT1618
Buck-Boost
1.6 to 18
34
500
1
DC/PWM
1.4
1.8
<1
MSOP-10
LTC3454
Buck-Boost
2.7 to 5.5
5.15
1A
1
DC/PWM
1
0.8
<1
3x3 DFN-10
* Output voltage and current depend on the choice of external components
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08
02
HIGH CURRENT LED DRIVERS FOR CAMERA FLASH/TORCH – INDUCTORLESS
High Current LED Drivers for Camera Flash/Torch – Inductorless
Our family of inductorless charge pump-based camera LED driver
products offers high efficiency and low ripple and can be used to
boost an input voltage to drive high current LEDs for camera torch
(continuous) and flash applications. By eliminating the inductor,
these switched capacitor converters provide a small solution
footprint and a simple design.
Applications:
. LED Camera Light Supply for Cellphones/DSCs/PDAs
Efficiency vs VIN
LTC3218: 400mA Single Wire Camera LED Charge Pump
100
2.2μF
2.9V TO 4.5V
DISABLED
ENABLED
ENABLED
CPO
4.7μF
LTC3218
80
70
60
ILED
ENF
GND
ENT
ISETF
50mA
150mA
300mA
50
LED
AOT2015
40
2.9
ISETT
3.1
3.3
ENT
0
0
0 (SHUTDOWN)
0
1
100mA (TORCH)
1
0
290mA
1
1
390mA (FLASH)
VIN (V)
3.7
3.5
ILED
ENF
Part
Number
CM
VIN
2.2μF
DISABLED
EFFICIENCY (%)
CP
90
3.9
4.1
4.3
4.5
VIN (V)
10.2k
1%
LTC3218: Actual Size,
Complete Solution
Conversion Total LED
Ratio/Boost Current
Factor
(mA)
Maximum
Max. # of
Operating
White LEDs
Efficiency**
x ILED
Dimming Control (%)
Frequency
(MHz)
IQ
(mA)
ISD
(µA)
Package
High Current (350mA to 1A) LED Drivers for Camera Flash - Inductorless
LTC3218
2.9 to 4.5
1x/2x
400
1 x 400mA*
Resistor/PWM
92
1
0.98
<1
2x3 DFN-10
LTC3214
2.9 to 4.4
1x/1.5x/2x
500
1 x 500mA*
Resistor/PWM
85
0.9
0.98
<2.5
3x3 DFN-10
LTC3217
2.9 to 4.5
1x/1.5x/2x
600
4 x 150mA*
Resistor/PWM
86
0.9
0.4
<4
3x3 QFN-16
LTC3215
2.9 to 4.4
1x/1.5x/2x
700
1 x 700mA*
Resistor/PWM
90
0.9
0.3
<2.5
3x3 DFN-10
LTC3216
2.9 to 4.4
1x/1.5x/2x
1000
1 x 1A*
Resistor/PWM
90
0.9
0.3
<2.5
3x4 DFN-12
* Flash Mode
** Dependent on VIN, VLED, ILED
04109 CS3_LIN_LED_FA_10–7–08.r2.indd 11
10/24/08 3:43:57 PM
MEDIUM CURRENT (100mA TO 350mA) LED DRIVERS – BUCK
09
03
Medium Current (100mA to 350mA) LED Drivers – Buck
Medium-current inductor-based step-down switching LED drivers
provide tiny, efficient high power LED lighting solutions for automotive, architectural and display backlighting. Key features include
wide-ranging True Color PWM dimming, wide input voltage range,
high side sensing and high switching frequency.
Applications:
. Automotive and Avionic Lighting
. Architectural Detail Lighting
. Display Backlighting
. Constant Current Sources
LT3592: 500mA Wide Input Voltage Range Step-Down
LED Driver with 10:1 Dimming
LT3592: Actual Size,
Complete Solution
LED Power Efficiency vs ILED
100
95
50/500mA Two Series Red LED Driver
90
VIN
0.1μF 10μH
1μF
SW
LT3592
DA
CAP
ON
BRAKE
SHDN
BRIGHT
OUT
140k
900kHz
Part
Number
Topology
80
75
70
65
+
200/20mV
–
60
0.47
4.7μF
55
50
51k
RT
GND
BRIGHT 500mA
85
BOOST
EFFICIENCY (%)
VIN
7V TO 32V
4
12
20
16
INPUT VOLTAGE (V)
8
VFB
24
28
10k
Dimming
Type
Max #
of LEDs
x ILED from
24VIN
LED
Configuration
Input
Voltage
Range
(V)
Max.
Output
Voltage
(V)
ISW (A)
Operating
Efficiency
(%)
Package
Medium Current (100mA to 350mA) LED Drivers – Buck
LT3591
Buck
80:1 PWM
5 x 200mA
Series
2.5 to 12
30
0.5
92
2x3 DFN-8
LT3517
Buck
5000:1
PWM
5 x 300mA
Series
3 to 30
(40VMAX)
30
1.5
92
4x4 QFN-16
TSSOP-16E
LT3592
Buck
10%/100%
Analog
6 x 350mA
Series
3 to 36
(60VMAX)
32
0.8
92
2x3 DFN-10
MSOP-10E
LT3496
Buck
3000:1
PWM
3 x 5 x 300mA
3 x Multiple
Series Strings
3 to 30
(40VMAX)
30
3 x 0.75
92
4x5 QFN-28
04109 CS3_LIN_LED_FA_10–7–08.r2.indd 12
10/24/08 3:43:58 PM
10
02
MEDIUM CURRENT (100mA TO 350mA) LED DRIVERS – BOOST
Medium Current (100mA to 350mA) LED Drivers – Boost
Efficiency vs ILED
Applications:
. Automotive and Avionic Lighting
. Architectural Detail Lighting
. Display Backlighting
. Constant Current Sources
95
PWM = 3V
CTRL = 0V TO 1.2V
90
EFFICIENCY (%)
85
LT3496: Actual Size,
Complete Solution
80
75
70
65
60
55
20
0
40
LT3496: Triple Output LED Driver
PVIN
12V
C1
2.2μF
L1
10μH
L2
10μH
D2
CAP1
C3
1μF
17
D3
CAP2
M1
LED3
TG3
M2
100mA
PWM1-3
SHDN
Part
Number
SW1
CAP1-3
LED1-3
VIN
PWM1-3
SHDN
10 LEDs
Topology
825k
OVP2
100mA
10 LEDs
OVP3
100mA
20k
SW2
20k
SW3
LT3496
GND
Dimming
Type
M3
825k
OVP1
20k
VIN
3V
C5
1μF
17
LED2
TG2
825k
10 LEDs
CAP3
C4
1μF
17
LED1
TG1
100
L3
10μH
D1
C2
1μF
80
60
ILED (mA)
Max #
of LEDs
x ILED from
12VIN
TG1-3
OVP1-3
VC1-3
VREF
FADJ
CTRL1-3
LED
Configuration
10k
470pF
Input
Voltage
Range
(V)
Max.
Output
Voltage
(V)
ISW (A)*
Operating
Efficiency
(%)
Package
Medium Current (100mA to 350mA) LED Drivers – Boost
LT3486
Dual Boost
1000:1
PWM
2 x 8 x 100mA
2 x Series
Strings
2.7 to 24
35
2 x 1.3
87
3x5 DFN-16
LT3517
Boost
5000:1
PWM
10 x 200mA
Series
3 to 30
(40VMAX)
45
1.5
87
4x4 QFN-16
TSSOP-16E
LT3518
Boost
5000:1
PWM
10 x 300mA
Series
3 to 36
(60VMAX)
45
2.3
87
4x4 QFN-16
TSSOP-16E
LT3496
Triple Boost
3000:1
PWM
3 x 10 x 100mA
3 x Series
Strings
3 to 30
(40VMAX)
45
3 x 0.75
87
4x5 QFN-28
* IOUT ~ 0.65 ISW x (VIN / VOUT). Estimate: may vary depending on external component selection.
04109 CS3_LIN_LED_FA_10–7–08.r2.indd 13
10/24/08 3:43:58 PM
MEDIUM CURRENT (100mA TO 350mA) LED DRIVERS – BUCK-BOOST
11
03
Medium Current (100mA to 350mA) LED Drivers – Buck-Boost
Efficiency
Applications:
. Automotive and Avionic Lighting
. Architectural Detail Lighting
. Display Backlighting
. Constant Current Sources
90
VIN = 10V
CTRL = VREF
80
LT3518: Full-Featured LED Driver with 2.3A Switch Current
70
EFFICIENCY (%)
LT3518: Actual Size,
Complete Solution
60
50
40
30
L1
4.3μH
VIN
8V TO 16V
SHDN VIN
D1
20
R1
3.92M
SW
0
C5
0.22μF
20
40
60
100
80
PWM DUTY CYCLE (%)
FB
R2
124k
PWM
PWM
TGEN
LT3518
RSENSE
330m7
VREF
ISN
CTRL
C1
2.2μF
TG
M1
SYNC
VC
300mA
ISP
RT SS
C2
4.7μF
GND
RT
6.04k
2MHz
C4
0.1μF
Part
Number
Topology
Dimming
Type
C3
0.1μF
Max #
of LEDs
x ILED from
12VIN
LED
Configuration
Input
Voltage
Range
(V)
Max.
Output
Voltage
(V)
ISW (A)*
Operating
Efficiency
(%)
Package
Medium Current (100mA to 350mA) LED Drivers – Buck-Boost
LT3517
Buck-Boost
5000:1
PWM
6 x 300mA
Series
3 to 30
(40VMAX)
45
1.5
80
4x4 QFN-16
TSSOP-16E
LT3518
Buck-Boost
5000:1
PWM
8 x 300mA
Series
3 to 36
(60VMAX)
45
2.3
80
4x4 QFN-16
TSSOP-16E
LT3496
Triple
Buck-Boost
3000:1
PWM
3x6x
100mA
3 to 30
(40VMAX)
45
3 x 0.75
80
4x5 QFN-28
3 x Series
Strings
* IOUT ~ 0.65 ISW x (VIN / VOUT). Estimate: may vary depending on external component selection.
04109 CS3_LIN_LED_FA_10–7–08.r2.indd 14
10/24/08 3:43:59 PM
12
02
L O W T O M E D I U M C U R R E N T ( 2 0 - 2 0 0 m A / L E D ) M U LT I D I S P L AY L E D D R I V E R S – I N D U C T O R B A S E D
Low to Medium Current (20-200mA/LED) Multidisplay LED Drivers – Inductor Based
Multidisplay inductor-based white LED drivers are capable of
driving up to 20 white LEDs from a single cell Li-Ion input. Key
features include high-voltage internal power switches, internal
Schottky diodes, adjustable switching frequency, DC dimming
control, open LED protection and optimized internal compensation.
They are ideal solutions for multipanel LCD backlight applications
or space-constrained portable applications such as cellular phones,
PDAs and digital cameras.
Applications:
. Main/Sub-Displays
. Digital Cameras, Sub-Notebook PCs
. PDAs, Handheld Computers
. Automotive
LED Efficiency and Current
vs PWM Duty Cycle
LT3486: Dual 1.3A White LED Step-Up Converter with 1000:1 Dimming Range
90
120
EFFICIENCY
12V (TYP)
9V TO 15V
EFFICIENCY (%)
COUT1
2.2μF
L2
10μH
5V
D1
COUT2
2.2μF
D2
C1 1μF
100
80
80
LED CURRENT
75
60
70
40
65
LED CURRENT (mA)
L1
10μH
85
CIN
10μF
20
VIN = 12V
8/8 LEDs
60
VIN
SW1
LUXEON
LEDs
LXCL-PWF1
0
SW2
OVP1
OVP2
VIN
CTRL1
CTRL2
OFF ON
SHDN
LT3486
VIN
REF
100mA
PWM2
PWM1
CREF
0.1μF
VC1 GND
RT
VC2
3.65k
DIMMING
INPUT 2
3.65k
21.5k
PWM
FREQ
1kHz
Q1
100k
2.2nF
2.2nF
Type
Max # of
LEDs x IOUT*
LED
Configuration
LT3486: Actual Size,
Complete Solution
PWM
FREQ
1kHz
Q2
RFB2
2Ω
RFB1
2Ω
Dimming
Type
0
100
100mA
22pF
DIMMING
INPUT 1
40
60
80
PWM DUTY CYCLE (%)
FB2
FB1
Part
Number
LUXEON
LEDs
LXCL-PWF1
20
100k
Input
Voltage
Range (V)
Max.
Output
Voltage (V)
ISW (mA)
Operating
Efficiency
(%)
Package
Low to Medium Current Multidisplay LED Drivers – Inductor Based
LT3466-1
LED Driver
and Boost
Converter
DC/PWM
10 x 25mA
Series
2.7 to 24
39.4
2 x 320
84
3x3 DFN-10
TSSOP-16E
LT3466
Dual LED
Driver
DC/PWM
2 x 25 x
25mA
Dual Series
Strings
2.7 to 24
39.4
2 x 320
84
3x3 DFN-10
TSSOP-16E
LTC3452
Synchronous
Buck-Boost
LED Driver
DC/PWM
5 x 20mA +
1 x 200mA
Parallel
2.7 to 5.5
4.5
1A
88
4x4 QFN-20
LT3486
Dual LED
Driver
1000:1
PWM
2x8x
100mA
Dual Series
Strings
2.7 to 24
35.4
2 x 1.3A
85
3x4 DFN-16
TSSOP-16E
* Dependent on Input Voltage, number of LEDs from a 12V Input
04109 CS3_LIN_LED_FA_10–7–08.r2.indd 15
10/24/08 3:43:59 PM
LOW CURRENT (20mA TO 50mA) LED DRIVERS – BUCK
13
03
Low Current (20mA to 50mA) LED Drivers – Buck
Low current inductor-based step-down switching LED drivers
provide tiny, efficient high power LED lighting solutions for
automotive, architectural and display backlighting. Key features
include wide-ranging True Color PWM dimming, wide input voltage
range, high side sensing and high switching frequency.
Applications:
. Automotive and Avionics Lighting
. Architectural Detail Lighting
. Display Backlighting
. Constant Current Sources
LT3590: Actual Size,
Complete Solution
Conversion Efficiency
LT3590: 48V Buck Mode 50mA LED Driver in 2mm x 2mm DFN
100
1μF
90
50mA
EFFICIENCY (%)
47
VIN
48V
1μF
CONTROL
VIN
LED
LT3590
VREG
0.1μF
Part
Number
Topology
70
60
470μH
CTRL
80
50
SW
40
GND
Dimming
Type
0
Max #
of LEDs
x ILED from
40VIN
10
20
30
LED CURRENT (mA)
LED
Configuration
Input
Voltage
Range
(V)
Max.
Output
Voltage
(V)
ISW (mA)
Operating
Efficiency
(%)
40
50
Package
Low Current (20mA to 50mA) LED Drivers – Buck
LT3590
Buck
10:1 DC
8 x 50mA
Series
4.5 to 55
40
80
90
2x2 DFN-6
SC-70
LT3517
Buck
5000:1
PWM
8 x 50mA
Series
3 to 30
(40VMAX)
40
1.5A
92
4x4 QFN-16
TSSOP-16E
LT3595
16-Channel
Buck
5000:1
PWM
16 x 10 x
50mA
16 x Multiple
Series Strings
4.5 to 45
45
16 x 0.09
92
5x9 QFN-56
LT3496
Buck
3000:1
PWM
3x8x
50mA
3 x Multiple
Series Strings
3 to 30
(40VMAX)
40
3 x 0.75
95
4x5 QFN-28
04109 CS3_LIN_LED_FA_10–7–08.r2.indd 16
10/24/08 3:44:00 PM
14
02
LOW CURRENT (20mA TO 50mA) LED DRIVERS – BOOST
Low Current (20mA to 50mA) LED Drivers – Boost
LT3593: 1MHz White LED Driver with Digitally Controlled Current
Conversion Efficiency
90
1μF
1μF
VIN
SW
CAP
LT3593
SHUTDOWN AND
CURRENT CONTROL
LED
CTRL
VIN = 3.6V
10 LEDs
80
EFFI CIENCY (%)
VIN
3V TO 5V
LT3593: Actual Size,
Complete Solution
10μH
70
60
50
GND
40
30
0
Part
Number
Type
Dimming
Type
Max #
of LEDs
x IOUT*
(VIN=3.6V)
LED
Configuration
Input
Voltage
Range
(V)
Max.
Output
Voltage
(V)
5
10
15
LED CURRENT (mA)
ISW (mA)*
Operating
Efficiency
(%)
Package
20
Low Current (20mA to 50mA) LED Drivers – Boost
LT3491
Boost LED
Driver
300:1
PWM
6 x 25mA
Series
2.5 to 12
27
260
76
SC70
LT3498
Boost LED
and OLED
Driver
DC/PWM
6 x 20mA
Series
2.5 to 12
32
300 +
180
77
2x3 DFN-12
LT3591
Boost LED
Driver
90:1
PWM
10 x 25mA
Series
2.5 to 12
42
450
77
2x3 DFN-8
LT3593
Boost LED
Driver
32:1
Digital
10 x 25mA
Series
2.5 to 5.5
45
550
80
2x2 DFN-6
ThinSOT
LT3497
Dual Boost
LED Driver
250:1
PWM
2 x 6 x 20mA
2 Parallel
Series Strings
of 6
2.5 to 10
32
2 x 300
77
2x3 DFN-10
LT3466
Dual Boost
LED Driver
DC/PWM
2 x 10 x
25mA
2 Parallel
Series Strings
of 10
2.7 to 24
40
2 x 320
84
3x3 DFN-10
LT3466-1
Boost LED
Driver + Boost
DC/PWM
10 x 25mA
Series
2.7 to 24
40
2 x 320
84
3x3 DFN-10
LT3598
6-Channel
Buck LED
Driver
1000:1
PWM
6 x 10 x
30mA
6 x Multiple
Series Strings
3 to 30
(40VMAX)
44
1.5A
88
4x4 QFN-24
LT1942
Quad DC/DC
Converter and
LED Driver
DC/PWM
12 x 25mA
2 Parallel
Series Strings
of 6
2.6 to 16
44
550
77
4x4 QFN-24
* IOUT ~ 0.65 ISW x (VIN / VOUT). Estimate: may vary depending on external component selection.
04109 CS3_LIN_LED_FA_10–7–08.r2.indd 17
10/24/08 3:44:01 PM
M U LT I C H A N N E L L E D D R I V E R S F O R L A R G E L C D PA N E L S ( 3 0 m A T O 5 0 m A )
15
03
Multichannel LED Drivers for Large LCD Panels (30mA to 50mA)
LT3598 Efficiency – Adaptive
Feedback Loop Maximizes Efficiency
LT3598: 1.5A Boost Converter with 6-Channel 30mA LED Driver
. Drives Six Strings of LEDs at Up to 30mA
. 2% Accurate LED Current Regulation
. Wide Input Voltage Range:
. Operation from 3V to 30V
. Transient Protection to 40V
. Output Voltage Up to 50V
. Regulates Current Even When V > V
. Disconnects LEDs in Shutdown
. Analog and PWM Dimming Control
. Programmable Open LED Protection (Regulated)
. OPENLED Alert Pin
. Programmable LED Temperature Derating
. Adjustable Frequency: 200kHz to 2.5MHz
. Synchronizable to an External Clock
. 4mm x 4mm QFN-24 Package
IN
100
90
EFFICIENCY
80
70
60
50
OUT
40
30
0
5
10
15
20
LED CURRENT (mA)
LT3598: Actual Size,
Complete Solution
LED Driver for 60 White LEDs
10μH
VIN
2.2μF
VIN
100k
SW
4.7μF
VOUT
VO_SW
OPENLED
SHDN
SHDN
PWM
PWM
SYNC
SYNC
2M
FB
61.9k
RT
LT3598
VREF
10k
CTRL
10k
43k
TSET
ISET
SS
LED1
LED2
LED3
LED4
LED5
LED6
GND VC
10nF
80k
04109 CS3_LIN_LED_FA_10–7–08.r2.indd 18
10k
20mA
3.01k
10nF
10/24/08 3:44:01 PM
16
02
M U LT I C H A N N E L L E D D R I V E R S F O R L A R G E L C D PA N E L S ( 3 0 m A T O 5 0 m A )
Multichannel LED Drivers for Large LCD Panels (30mA to 50mA)
LT3595: 16-Channel Buck Mode 50mA LED Driver
Conversion Efficiency
. Open LED Detection and Thermal Protection
. 5mm × 9mm × 0.75mm QFN-56 Package
100
EFFICIENCY (%)
. 4.5V to 45V Input Supply Range
. Up to 50mA LED Current per Channel
. 100mA, 45V Internal Switches
. 8% Relative LED Current Match at 20mA
. 16 Independent LED Channels
. 5000:1 True Color PWM Dimming Range
. LEDs Disconnected in Shutdown
. Internal Schottky Diodes
. Low Quiescent Current
. 2MHz Switching Frequency
. R Pin Sets Master LED Current
. Typical Efficiency: 92%
5000:1 PWM Dimming at 100Hz
95
90
VPWM
5V/DIV
ISW
50mA/DIV
85
10
20
30
ILED (mA)
40
50
ILED
20mA/DIV
SET
400ns/DIV
10 LEDS AT 40mA
0.47µF
0.47µF
0.47µF
0.47µF
100µH
VIN
45V
100µH
30W LED Driver for 160 LEDs (16 Strings, 10 LEDs per String) at 50mA
0.47µF
0.47µF
0.47µF
0.47µF
100µH
100µH
100µH
100µH
100µH
100µH
10µF
LT3595: Actual Size,
Complete Solution
VCC
LED
BRIGHTNESS
CONTROL
3V TO
5.5V
L1 SW1
OPENLED
PWM1
PWM2
PWM3
PWM4
PWM5
PWM6
PWM7
PWM8
SHDN
VCC
L16 SW16
L2
SW2
SW3
L3
SW4
L4
L5
SW5
L6
SW6
SW7
L7
SW8
L10
PWM9
PWM10
PWM11
PWM12
PWM13
PWM14
PWM15
PWM16
GND
RSET
SW9 L9
LT3595
L15
SW15 VIN SW14
L14
SW13
L13
L12
SW12
L11
SW11 VIN SW10
04109 CS3_LIN_LED_FA_10–7–08.r2.indd 19
0.47µF
0.47µF
0.47µF
0.47µF
0.47µF
LED
BRIGHTNESS
CONTROL
100µH
100µH
100µH
100µH
100µH
100µH
100µH
100µH
10µF
0.47µF
L8
30.1k
100k
0.47µF
0.47µF
10/24/08 3:44:02 PM
L O W C U R R E N T M U LT I D I S P L AY L E D D R I V E R S – I N D U C T O R L E S S
17
03
Low Current Multidisplay LED Drivers – Inductorless
Applications:
Our family of inductorless, charge pump-based multidisplay
LED drivers feature the highest level of integration, smallest
footprint and highest efficiency. Individual display driver outputs
eliminate the need for ballast resistors, while the universal topology
enables an even higher level of design flexibility without display
type restrictions. These ICs optimize designs for a wide range of
applications, from general illumination and keypads to portable
products such as multidisplay cellular phones and high current/
high resolution camera flash devices.
. Video Phones with QVGA+ Displays
. Keyboard Lighting
. General Lighting
LTC3220/-1: Actual Size,
Complete Solution
LTC3220/-1: 360mA Universal 18-Channel LED Driver
2.2μF
2.2μF
RGB1
C1P C1M C2P C2M
VIN
CPO
VIN
LTC3220
LTC3220-1
2.2μF
DVCC
DVCC
ULED1-18
SCL/SDA
RST
RESET
Part
Number
VIN
(V)
RGB3
RGB4
MAIN
4.7μF
18
0.1μF
I2C
RGB2
GND
Conversion
Ratio/
Boost
Factor
Total
LED
Current
(mA)
Max. #
of White
LEDs
x ILED
Display
Types
Number
of
Displays
Dimming
Control
Maximum
Operating
Efficiency***
(%)
Frequency
(MHz)
IQ
(µA)
ISD
(µA) Package
Low Current Multidisplay LED Drivers – Inductorless
++
LTC3212
2.7 to
5.5
1x/2x
75
3 x25mA
RGB
3
1-wire
81
0.9
400
<3
2x3 DFN-12
LTC3230
2.7 to
5.5
1x/1.5x/2x
125
5x25mA
Main, Sub,
+ 2 LDOs
2
1-wire
91
0.8
400
<3
3x3 QFN-20
LTC3219
2.9 to
5.5
1x/1.5x/2x
250
9x28mA
Universal
Up to 9
I2C
91
0.85
400
<2
3x3 QFN-20
LTC3220
LTC3220-1+
2.9 to
5.5
1x/1.5x/2x
360
18x20mA
Universal
Up to 18
I2C
91
0.85
500
<4
4x4
UTQFN-28
LTC3206
2.8 to
4.5
1x/1.5x
400
(5+3+3)x
35mA
Main, SUB, 3
RGB
SPI*
90
1
180
<1
4x4 QFN-24
LTC3210/-1
2.9 to
4.5
1x/1.5x/2x
500
4x25mA +
1**x400mA
Main, CAM
2
1-wire
93
0.8
400
<3
3x3 QFN-16
LTC3209-1
2.9 to
4.5
1x/1.5x/2x
600
6x25mA +
1x15mA +
1**x400mA
Main, Aux,
CAM
3
I2C
94
0.85
400
<3
4x4 QFN-20
LTC3209-2
2.9 to
4.5
1x/1.5x/2x
600
5x25mA +
1x15mA +
2**x200mA
Main, Aux,
CAM
3
I2C
94
0.85
400
<3
4x4 QFN-20
LTC3207
2.9 to
5.5
1x/1.5x/2x
600
12x28mA +
1**x425mA
Universal,
CAM
Up to 13
I2C
91
0.85
500
<2
4x4 QFN-24
LTC3208
2.9 to
4.5
1x/1.5x/2x
1000
(4+2+3+4)x
27.5mA +
4x100mA
Main, SUB, 5
RGB, Aux,
CAM
I2C
95
0.85
250
<1
5x5 QFN-32
* Serial Peripheral Interface
** High Current Camera LED >=200-425mA
*** Dependent on VIN, VLED, ILED
04109 CS3_LIN_LED_FA_10–7–08.r2.indd 20
+
Different I2C address
Red, Green, Blue LEDs
++
10/24/08 3:44:03 PM
18
02
LOW CURRENT GENERAL PURPOSE LED DRIVERS – INDUCTORLESS
Low Current General Purpose LED Drivers – Inductorless
Our family of charge pumps includes the widest selection
of simple and compact inductorless DC/DC converter
designs. These step-up converters offer low ripple and
can be used to boost an input voltage to drive parallel
LEDs. By eliminating the inductor, these switched capacitor
converters provide a small solution footprint and a simple
design. The ICs efficiently drive low current white LEDs for
a wide range of applications.
Output Ripple vs Load Current
Applications:
30
COUT = 2.2μF
VIN = 3.6V
25
OUTPUT RIPPLE (mVp-p)
. 2 AA Cell to 3.3V
. Li-Ion/Polymer to 5V
. USB On-the-Go Devices
. LED Drivers
. Handheld Devices
20
LTC3204-5
15
10
LTC3204B-5
5
0
0
25
50
75
100
LOAD CURRENT (mA)
125
150
LTC3204/B: Low Noise, Miniature 2x2 DFN Regulated Charge Pump Doubler
2.2μF
LTC3204-5: Actual Size,
Complete Solution
3V TO 4.2V
Li-Ion
BATTE RY
C–
V IN
+
2.2μF
(APPLY PWM WAVEFORM FOR
ADJUSTABLE BRIGHTNESS CONTROL)
Dimming
Type
DRIVE UP TO 5 LEDS
2.2μF
LTC3204-5/
LTC3204B-5
SHDN
ON OFF
Part
Number
C+
V OUT
1007
1007
1007
1007
1007
GND
V SHDN
# of
LEDs
t
LED
Configuration
VIN (V)
Output
Voltage (V)
Total
Output
Current
(mA)
Maximum
Operating
Efficiency**
(%)
Package
Low Current LED Drivers – Inductorless
LTC3200
PWM
5+
parallel
2.7 to 4.5
Adj (1.268 to 5.4)
100
87
MSOP-8
LTC3200-5
PWM
5+
parallel
2.7 to 4.5
5
100
87
ThinSOT™
LTC3201
DAC
5+
parallel
2.7 to 4.5
Adj (3.19 to 4.6)
100
87
MSOP-10
LTC3202
DAC
6+
parallel
2.7 to 4.5
Adj (3.3 to 4.0)
125
87
3x3 DFN-10
MSOP-10
LTC3204-5*
PWM
6+
parallel
2.7 to 5.5
5
150
93
2x2 DFN-6
LTC3204B-5
PWM
6+
parallel
2.7 to 5.5
5
150
93
2x2 DFN-6
LTC3203B
PWM
6+
parallel
2.7 to 5.5
Adj (0.9 to 5.4)
500
90
3x3 DFN-10
LTC3203-1*
PWM
6+
parallel
2.7 to 5.5
4.5, 5
500
90
3x3 DFN-10
LTC3203B-1
PWM
6+
parallel
2.7 to 5.5
4.5, 5
500
90
3x3 DFN-10
* Burst Mode® Operation
** Dependent on VIN, VLED, ILED
04109 CS3_LIN_LED_FA_10–7–08.r2.indd 21
10/24/08 3:44:03 PM
ORGANIC LED (OLED) BIAS – LOW TO HIGH CURRENT (50mA TO 2A) DRIVERS
19
03
Organic LED (OLED) Bias – Low to High Current (50mA to 2A) Drivers
Linear Technology delivers highly integrated solutions for OLED bias
applications. Key features include output disconnect, soft start and
integrated Schottky diodes. Their small circuit size and high efficiency
make them ideal solutions for space-conscious portable device
applications such as cellular phones and media players.
Applications:
. Organic LED Power Supply
. Digital Cameras
. White LED Power Supply
. Cellular Phones
. Medical Diagnostic Equipment
. Local ±5V or ±12V Supply
. TFT-LCD Bias Supply
LT3494: Actual Size,
Complete Solution
LT3494: Micropower Low Noise Boost Converter
with Output Disconnect
AVDD Efficiency vs VIN
90
280
VIN = 3.6V
LOAD FROM
CAPACITOR
80
15μH
LOAD FROM
VOUT
EFFICIENCY (%)
70
4.7μF
0.22μF
SW
CAP
VCC
VOUT
LT3494
2.21M
SHDN
FB
CTRL
GND
VOUT
16V
16mA
2.2μF
Part
Number
Configuration
Topology
Max.
Output
Voltage
(V)
200
60
160
50
120
40
80
30
40
20
0.1
Input
Voltage
Range
(V)
240
1
10
LOAD CURRENT (mA)
POWER LOSS (mW)
VIN
3V
TO 4.2V
0
100
ISW (mA)*
Operating
Efficiency
(%)
Package
Low to High Current (50mA to 2A) LED Drivers for Organic LED (OLED)
LTC3459
Single
Synchronous Boost
1.5 to 5.5
10
60
89
ThinSOT™
LT3464
Single
Boost
2.3 to 10
34
85
84
ThinSOT™
LT3494/A
Single
Boost
2.3 to 16
40
150/300
85
2x3 DFN-8
LT3498
Dual
Dual Boost
2.5 to 12
32
300/180
77
2x3 DFN-12
LT3463
Dual
Boost and Inverter
2.4 to 15
±40
180/320
77
3x3 DFN-10
LT3472
Dual
Boost and Inverter
2.2 to 16
±40
250/300
83
3x3 DFN-10
LT3582
Dual
Boost and Inverter
2.58 to 5.5
±14
290/500
83
3x4 QFN-16
LT3495(B)/-1
Single
Boost
2.3 to 16
40
350/650
85
2x3 DFN-10
LT1613
Single
Boost
0.9 to 10
34
550
89
ThinSOT™
LT3487
Dual
Boost and Inverter
2.3 to 16
±28
750/900
77
3x3 DFN-10
LT3473/A
Single
Boost
2.2 to 16
36
1.2A
77
3x3 DFN-8
LT3467/A
Single
Boost
2.4 to 16
40
1.4A
90
ThinSOT™
LT3471
Dual
Boost or Inverter
2.4 to 16
±40
2 x 1.5A
86
3x3 DFN-10
LTC3458/L
Single
Synchronous Boost
1.5 to 6
7.5/6
1.4A/1.7A
96
3x4 DFN-12
* IOUT ~ 0.65 ISW x (VIN / VOUT). Estimate: may vary depending on external component selection.
04109 CS3_LIN_LED_FA_10–7–08.r2.indd 22
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20
02
LCD AND CCD BIAS POWER
LCD and CCD Bias Power
Applications:
LCD and CCD Bias ICs deliver highly compact and efficient power supply solutions for small
LCD displays. Key features include wide input voltage range, built-in inrush current limiting,
output disconnect and power saving controls to simplify the task of implementing powerfriendly LCD displays.
. Digital Still and Video Cameras
. Cellular Handsets with Color Display
. Scanner and Display Systems
. Handheld Instruments
. CCD Imager Bias
. PDAs
LT3587: High Voltage Monolithic Inverter and Dual Boost
VVIN
2.5V TO 6V
10μH
15μH
1μF
2.2μF
SW3
VIN
SW1
CAP1
CAP3
IFB3
10μF
CCD POSITIVE
+15V, 50mA
VOUT1
1M
8.06k
GND
LT3587: Actual Size,
Complete Solution
FB1
LT3587
2.7pF
EN/SS3
CDD+ = 50mA
85 CDD– = 100mA
LED = 20mA
EFFICIENCY (%)
6.8pF
2.2μF
VVIN
2.5V TO 6V
15μH
700
600
15μH
22μF
CCD NEGATIVE
–8V, 100mA
ALL CHANNELS
ENABLED
75
70
500
400
CDD–
65
LED
60
300
POWER DISSIPATION
ALL CHANNELS
ENABLED
200
100
55
50
1
0.5
NORMALIZED CURRENT
0
Part
Number
Number of
Outputs
VIN (V)
VOUT (V)
ISW (A)*
POWER DISSIPATION (mW)
FB2
SW2
CDD+
80
1M
FLT
800
90
LED DRIVER
20mA, UP TO 6 LEDS
VOUT3
VFB3
EN/SS1
Frequency
IQ (µA)
Output
Disconnect
Package
ThinSOT
0
1.5
Low to Medium Current LED Drivers for LCD and CCD Biasing
LT1611
1
1.1 to 10
-34
0.55
1.4MHz
3mA
–
LT1945
1
1.2 to 15
±34
0.25
Constant Off-Time
20
–
MSOP-10
LT1618
1
1.6 to 18
36
1.50
1.4MHz
1.8mA
–
MSOP-10
LT3472
1
2.2 to 16
±34
0.35
1.2MHz
2.8mA
Yes
3x3 DFN-10
LT3473/A
1
2.2 to 16
34
1.20
1.2MHz
150
Yes
3x3 DFN-8
LT3464
1
2.3 to 10
34
0.085
Constant Off-Time
25
–
ThinSOT
LT3467
1
2.4 to 16
40
1.10
1.3MHz
1mA
–
ThinSOT
LT3479
1
2.5 to 24
40
3.00
3.5MHz
5mA
–
3x4 DFN-14
TSSOP-16
LT3461/A
1
2.5 to 16
38
0.30
1.3MHz/ 3MHz
2.8mA
–
ThinSOT
LT1930/A
1
2.6 to 16
34
1.00
1.2MHz/ 2.2MHz
4.2mA/5.5mA
–
ThinSOT
LT1931/A
1
2.6 to 16
-34
1.00
1.2MHz/ 2.2MHz
5.8mA
–
ThinSOT
LTC1697
1
2.8 to 5.5
6
0.9
300kHz
0.9mA
–
MSOP-10
LT1617/-1
2
1.2 to 15
-34
0.35/0.10
Constant Off-Time
20
–
ThinSOT
LT3463/A
2
2.4 to 15
±40
0.25 x 2
Constant Off-Time
40
Yes
3x3 DFN-10
LT3587
4
2.5 to 6
±32
0.8/0.4/0.9
1.0MHz
2.4mA
Yes
3x3 QFN-20
LT3471
2
2.4 to 16
±40
2 x 1.30
1.2MHz
2.5mA
–
3x3 DFN-10
LT3466-1
2
2.7 to 24
40
0.32 x 2
1.0MHz
5mA
–
3x3 DFN-10
TSSOP-16E
LTC3450
3
1.5 to 4.6
±15
0.09
550kHz
75
–
3x3 QFN-16
LTC3524
5
2.5 to 6.0
5, ±20
0.5
1.5MHz
4.2mA
Yes
4x4 QFN-24
LT1942
4
2.6 to 16
44
0.55/0.15/0.5/0.5
1MHz
7mA
Yes
4x4 QFN-24
* IOUT ~ 0.65 ISW x (VIN / VOUT). Estimate: may vary depending on external component selection.
04109 CS3_LIN_LED_FA_10–7–08.r2.indd 23
10/24/08 3:44:04 PM
Sales Offices
N ORTH A M ERICA
N O RTH E R N C A L IF O R NI A /
N E VA D A
Indiana
Tel: (317) 581-9055
Bay Area
720 Sycamore Dr.
Milpitas, CA 95035
Tel: (408) 428-2050
Fax: (408) 432-6331
Iowa
Tel: (319) 393-5763
Sacramento / Nevada
2260 Douglas Blvd., Ste. 280
Roseville, CA 95661
Tel: (916) 787-5210
Fax: (916) 787-0110
PA C IFIC N O RTH WE S T
Denver
7007 Winchester Cir., Ste. 130
Boulder, CO 80301
Tel: (303) 926-0002
Fax: (303) 530-1477
Portland
5005 SW Meadows Rd., Ste. 410
Lake Oswego, OR 97035
Tel: (503) 520-9930
Fax: (503) 520-9929
Salt Lake City
Tel: (801) 731-8008
Seattle
2018 156th Ave. NE, Ste. 100
Bellevue, WA 98007
Tel: (425) 748-5010
Fax: (425) 748-5009
SO U TH W E ST A R EA
Los Angeles
21243 Ventura Blvd., Ste. 238
Woodland Hills, CA 91364
Tel: (818) 703-0835
Fax: (818) 703-0517
Orange County
15375 Barranca Pkwy., Ste. A-213
Irvine, CA 92618
Tel: (949) 453-4650
Fax: (949) 453-4765
Phoenix
2085 E. Technology Cir., Ste. 101
Tempe, AZ 85284
Tel: (480) 777-1600
Fax: (480) 838-1104
San Diego
5090 Shoreham Place, Ste. 110
San Diego, CA 92122
Tel: (858) 638-7131
Fax: (858) 638-7231
C E N TR A L A R E A
Chicago
2040 E. Algonquin Rd., Ste. 512
Schaumburg, IL 60173
Tel: (847) 925-0860
Fax: (847) 925-0878
Cleveland
7550 Lucerne Dr., Ste. 106
Middleburg Heights, OH 44130
Tel: (440) 239-0817
Fax: (440) 239-1466
Columbus
Tel: (614) 488-4466
Detroit
39111 West Six Mile Road
Livonia, MI 48152
Tel: (734) 779-1657
Fax: (734) 779-1658
04109 CS3_LIN_LED_FA_10–7–08.r2.indd 24
Kansas
Tel: (913) 829-8844
Minneapolis
7805 Telegraph Rd., Ste. 225
Bloomington, MN 55438
Tel: (952) 903-0605
Fax: (952) 903-0640
Wisconsin
Tel: (262) 859-1900
NO RT HE A S T A REA
Boston
15 Research Place
North Chelmsford, MA 01863
Tel: (978) 656-4750
Fax: (978) 656-4760
Connecticut
Tel: (860) 228-4104
Philadelphia
3220 Tillman Dr., Ste. 120
Bensalem, PA 19020
Tel: (215) 638-9667
Fax: (215) 638-9764
S O UT HE A S T A R EA
Atlanta
Tel: (770) 888-8137
Austin
8500 N. Mopac, Ste. 603
Austin, TX 78759
Tel: (512) 795-8000
Fax: (512) 795-0491
Dallas
17000 Dallas Pkwy., Ste. 200
Dallas, TX 75248
Tel: (972) 733-3071
Fax: (972) 380-5138
Fort Lauderdale
Tel: (954) 473-1212
Houston
1080 W. Sam Houston Pkwy., Ste. 225
Houston, TX 77043
Tel: (713) 463-5001
Fax: (713) 463-5009
Huntsville
Tel: (256) 881-9850
Orlando
Tel: (407) 688-7616
Raleigh
15100 Weston Pkwy., Ste. 202
Cary, NC 27513
Tel: (919) 677-0066
Fax: (919) 678-0041
Tampa
Tel: (813) 634-9434
CA NA DA
Calgary, AB
Tel: (403) 455-3577
Montreal, QC
Tel: (450) 689-2660
Ottawa, ON
Tel: (613) 421-3090
Toronto, ON
Tel: (440) 239-0817
Vancouver, BC
Tel: (604) 729-1204
ASIA
EU R OPE
AU S T RAL IA / N EW ZEALAN D
F IN L AN D
Linear Technology Corporation
133 Alexander Street
Crows Nest NSW 2065
Australia
Tel: +61 (0)2 9432 7803
Fax: +61 (0)2 9439 2738
Linear Technology AB
Teknobulevardi 3-5
P.O. Box 35
FIN-01531 Vantaa
Finland
Tel: +358 (0)9 2517 8200
Fax: +358 (0)9 2517 8201
C H IN A
Linear Technology Corp. Ltd.
Units 1503-04, Metroplaza Tower 2
223 Hing Fong Road
Kwai Fong, N.T., Hong Kong
Tel: +852 2428-0303
Fax: +852 2348-0885
Linear Technology Corp. Ltd.
Room 2701, City Gateway
No. 398 Cao Xi North Road
Shanghai, 200030, PRC
Tel: +86 (21) 6375-9478
Fax: +86 (21) 5465-5918
Linear Technology Corp. Ltd.
Room 816, 8/F
China Electronics Plaza B
No. 3 Dan Ling Rd., Hai Dian District
Beijing, 100080, PRC
Tel: +86 (10) 6801-1080
Fax: +86 (10) 6805-4030
Linear Technology Corp. Ltd.
Room 2604, 26/F
Excellence Times Square Building
4068 YiTian Road, Futian District
Shenzhen, 518048, PRC
Tel: +86 755-8236-6088
Fax: +86 755-8236-6008
JAPAN
Linear Technology KK
8F Shuwa Kioicho Park Bldg.
3-6 Kioicho Chiyoda-ku
Tokyo, 102-0094, Japan
Tel: +81 (3) 5226-7291
Fax: +81 (3) 5226-0268
Linear Technology KK
6F Kearny Place Honmachi Bldg.
1-6-13 Awaza, Nishi-ku
Osaka-shi, 550-0011, Japan
Tel: +81 (6) 6533-5880
Fax: +81 (6) 6543-2588
Linear Technology KK
7F, Sakuradori Ohtsu KT Bldg.
3-20-22 Marunouchi, Naka-ku Nagoya-shi,
460-0002, Japan
Tel: +81 (52) 955-0056
Fax: +81 (52) 955-0058
F RAN C E
Linear Technology S.A.R.L.
Parc Tertiaire Silic
2 Rue de la Couture, BP10217
94518 Rungis Cedex
France
Tel: +33 (1) 56 70 19 90
Fax: +33 (1) 56 70 19 94
G ERMAN Y
Linear Technology GmbH
Osterfeldstrasse 84, Haus C
D-85737 Ismaning
Germany
Tel: +49 (89) 962455-0
Fax: +49 (89) 963147
Linear Technology GmbH
Haselburger Damm 4
D-59387 Ascheberg
Germany
Tel: +49 (2593) 9516-0
Fax: +49 (2593) 951679
Linear Technology GmbH
Jesinger Strasse 65
D-73230 Kirchheim/Teck
Germany
Tel: +49 (0)7021 80770
Fax: +49 (0)7021 807720
ITALY
Linear Technology Italy Srl
Orione 3, C.D. Colleoni
Via Colleoni, 17
I-20041 Agrate Brianza (MI)
Italy
Tel: +39 039 596 5080
Fax: +39 039 596 5090
S WED EN
Linear Technology AB
Electrum 204
Isafjordsgatan 22
SE-164 40 Kista
Sweden
Tel: +46 (8) 623 16 00
Fax: +46 (8) 623 16 50
U N IT ED K INGDOM
K OREA
Linear Technology Korea Co., Ltd.
Yundang Building, #1002
Samsung-Dong 144-23
Kangnam-Ku, Seoul
135-090 Korea
Tel: +82 (2) 792-1617
Fax: +82 (2) 792-1619
Linear Technology (UK) Ltd.
3 The Listons, Liston Road
Marlow, Buckinghamshire SL7 1FD
United Kingdom
Tel: +44 (1628) 477066
Fax: +44 (1628) 478153
S IN G APORE
Linear Technology Pte. Ltd.
507 Yishun Industrial Park A
Singapore 768734
Tel: +65 6753-2692
Fax: +65 6752-0108
TAIWAN
Linear Technology Corporation
8F-1, 77, Nanking E. Rd., Sec. 3
Taipei, Taiwan
Tel: +886 (2) 2505-2622
Fax: +886 (2) 2516-0702
10/24/08 3:44:06 PM
Linear Technology Corporation
1630 McCarthy Blvd.
Milpitas, CA 95035-7417
1-800-4-LINEAR
408-432-1900
www.linear.com
LW100815KU
Archway image on Front cover
© Philips, Lumileds
04109 CS3_LIN_LED_FA_10–7–08.r2.indd 25
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