LT3596
60V Step-Down LED Driver
FeaTures
DescripTion
The LT®3596 is a 60V step-down LED Driver. It achieves
10,000:1 digital PWM dimming at 100Hz with fast NPN
current sources driving up to 10 LEDs in each channel.
100:1 LED dimming can also be done with analog control
of the CTRL1-3 pin.
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300mA Buck Regulator, Drives Up to 10 LEDs per
Channel with Fast NPN Current Sources
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Fast Current Sources for <1µs Pulse Widths
(10,000:1 True Color PWM™ Dimming at 100Hz)
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LEDs Disconnected in Shutdown
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Adaptive V
for Increased Efficiency
OUT
The step-down switching frequency is programmable
between 200kHz and 1MHz and is synchronizable to an
external clock. The LT3596 also provides maximum LED
brightness while adhering to manufacturers’ specifica-
tions for thermal derating. The derate temperature is
programmedbyplacinganegativetemperaturecoefficient
(NTC) resistor on the master control pin.
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6V to 60V Input Voltage Range
1.5% ꢀccurate LED Current Matching
External Resistors Set LED Current for Each Channel
Requires No External Compensation
ProgrammableSwitchingFrequency(200kHzto1MHz)
Synchronizable to External Clock
Open, Short LED Detection and Reporting
Programmable LED Thermal Derating and Reporting
Programmable Temperature Protection
5mm × 8mm Thermally Enhanced QFN Package with
0.6mm High Voltage Pin Spacing
The LT3596 adaptively controls V
in order to achieve
OUT
optimalefficiency.Otherfeaturesinclude:1.5%LEDcurrent
matching between channels, open LED reporting, shorted
LEDpinprotectionandreporting, programmableLEDcur-
rent and programmable temperature protection.
applicaTions
L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear
Technology Corporation and True Color PWM is a trademark of Linear Technology Corporation.
ꢀll other trademarks are the property of their respective owners.
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LED Billboards and Signboards
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Mono, Multi, Full Color LED Displays
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Large Screen Display LED Backlighting
ꢀutomotive, Industrial and Medical Displays
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Typical applicaTion
48V 1MHz Step-Down 8W, 100mA LED Driver (Eight White LEDs per Channel)
V
IN
48V
5V
BIAS
V
BIAS
IN
10µF
4.7µF
270k
91k
BOOST
SW
EN/UVLO
100µH
100nF
10,000:1 PWM Dimming at 100Hz
V
OUT
4.7µF
LT3596
100k
3.65k
DA
GND
SYNC
SYNC
RT
PWM
2V/DIV
33.2k
FB
PWM1
PWM2
PWM3
PWM1
PWM2
PWM3
V
OUT
I
CTRL1
CTRL2
CTRL3
CTRL1
CTRL2
CTRL3
LED
50mA/DIV
BIAS
100k
LED1
LED2
LED3
FAULT
FAULT
3596 TA01b
200ns/DIV
V
REF
3696 TA01a
90.9k
10k
I
I
I
SET1
SET2
SET3
TSET
CTRLM
100k
49.9k
20k
20k
20k
3596f
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