LED Driver. LT3518 Datasheet

LT3518 Driver. Datasheet pdf. Equivalent

Part LT3518
Description Full-Featured LED Driver
Feature LT3518 Full-Featured LED Driver with 2.3A Switch Current FEATURES n 3000:1 True Color PWM™ Dimming .
Manufacture Linear Technology
Total Page 20 Pages
Datasheet
Download LT3518 Datasheet



LT3518
LT3518
Full-Featured LED Driver
with 2.3A Switch Current
FEATURES
n 3000:1 True Color PWMDimming Ratio
n 2.3A, 45V Internal Switch
n 100mV High Side Current Sense
n Open LED Protection
n Adjustable Frequency: 250kHz to 2.5MHz
n Wide Input Voltage Range:
Operation from 3V to 30V
Transient Protection to 40V
n Operates in Boost, Buck Mode and Buck-Boost Mode
n Gate Driver for PMOS LED Disconnect
n Constant-Current and Constant-Voltage Regulation
n CTRL Pin Provides 10:1 Analog Dimming
n Low Shutdown Current: <1μA
n Available in (4mm × 4mm) 16-Lead QFN and 16-Pin
TSSOP Packages
APPLICATIONS
n Display Backlighting
n Automotive and Avionic Lighting
n Illumination
n Scanners
DESCRIPTION
The LT®3518 is a current mode DC/DC converter with an
internal 2.3A, 45V switch specifically designed to drive
LEDs. The LT3518 operates as a LED driver in boost, buck
mode and buck-boost mode. It combines a traditional
voltage loop and a unique current loop to operate as a
constant-current source or constant-voltage source. Pro-
grammable switching frequency allows optimization of the
external components for efficiency or component size. The
switching frequency of the LT3518 can be synchronized
to an external clock signal. The LED current is externally
programmable with a 100mV sense resistor. The external
PWM input provides 3000:1 LED dimming. The CTRL pin
provides further 10:1 dimming ratio.
The LT3518 is available in the tiny footprint 16-lead QFN
(4mm × 4mm) and the 16-pin TSSOP package. The LT3518
provides a complete solution for both constant-voltage
and constant-current applications.
L, LT, LTC and LTM are registered trademarks of Linear Technology Corporation. True Color
PWM is a trademark of Linear Technology Corporation. Patent Pending. All other trademarks
are the property of their respective owners. Protected by U.S. Patents, including 7199560,
7321203, 7746300.
TYPICAL APPLICATION
1.5A Buck Mode LED Driver
PVIN
24V
VIN
3.3V
2.2μF
VREF
PWM
68mΩ M1
2.2μF
ISP
VIN
SHDN
ISN TG
SW
LT3518
CTRL
FB
PWM
SS
SYNC
RT
TGEN VREF VC GND
0.1μF
1.5A
16.9k
1MHz
10μF
15μH
0.1μF
3518 TA01a
Efficiency
100
CTRL = VREF
90
80
70
60
50
40
0
20 40 60 80
PWM DUTY CYCLE (%)
100
3518 TA01b
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LT3518
LT3518
ABSOLUTE MAXIMUM RATINGS (Note 1)
VIN, SHDN, PWM, TGEN (Note 3)..............................40V
SW, ISP, ISN, TG........................................................45V
TG Pin Below ISP Pin................................................10V
FB, SYNC, SS, CTRL ...................................................6V
VC, RT, VREF ................................................................3V
Operating Junction Temperature Range (Notes 2, 4)
LT3518E............................................. –40°C to 125°C
LT3518I.............................................. –40°C to 125°C
LT3518H ............................................ –40°C to 150°C
Storage Temperature Range
QFN.................................................... –65°C to 150°C
TSSOP ............................................... –65°C to 150°C
Lead Temperature (Soldering, 10 sec)
TSSOP .............................................................. 300°C
PIN CONFIGURATION
TOP VIEW
16 15 14 13
SW 1
12 FB
SW 2
11 VC
17
VIN 3
10 CTRL
SHDN 4
9 PWM
5678
UF PACKAGE
16-LEAD (4mm = 4mm) PLASTIC QFN
TJMAX = 125°C, θJA = 36°C/W
EXPOSED PAD (PIN 17) IS GND, MUST BE SOLDERED TO PCB
TOP VIEW
VIN 1
SHDN 2
VREF 3
RT 4
SYNC 5
SS 6
PWM 7
CTRL 8
16 SW
15 SW
14 TG
17 13 ISP
GND 12 ISN
11 TGEN
10 FB
9 VC
FE PACKAGE
16-LEAD PLASTIC TSSOP
TJMAX = 150°C, θJA = 40°C/W, θJC(PAD) = 10°C/W
ORDER INFORMATION
LEAD FREE FINISH
TAPE AND REEL
PART MARKING*
PACKAGE DESCRIPTION
TEMPERATURE RANGE
LT3518EUF#PBF
LT3518EUF#TRPBF
3518
16-Lead (4mm × 4mm) Plastic QFN –40°C to 125°C
LT3518IUF#PBF
LT3518IUF#TRPBF
3518
16-Lead (4mm × 4mm) Plastic QFN –40°C to 125°C
LT3518HUF#PBF
LT3518HUF#TPBF
3518
16-Lead (4mm × 4mm) Plastic QFN –40°C to 150°C
LT3518EFE#PBF
LT3518EFE#TRPBF
3518FE
16-Lead Plastic TSSOP
–40°C to 125°C
LT3518IFE#PBF
LT3518IFE#TRPBF
3518FE
16-Lead Plastic TSSOP
–40°C to 125°C
LT3518HFE#PBF
LT3518HFE#TRPBF
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16-Lead Plastic TSSOP
–40°C to 150°C
Consult LTC Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container.
Consult LTC Marketing for information on non-standard lead based finish parts.
For more information on lead free part marking, go to: http://www.linear.com/leadfree/
For more information on tape and reel specifications, go to: http://www.linear.com/tapeandreel/
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