LT3596 Datasheet, PDF (1/20 Pages) Linear Technology – 60V Step-Down LED Driver

LT3596
60V Step-Down LED Driver
Features
n _{300mA Buck Regulator, Drives Up to 10 LEDs per}
Channel with Fast NPN Current Sources
n _{Fast Current Sources for <1µs Pulse Widths}
(10,000:1 True Color PWM™ Dimming at 100Hz)
n _{LEDs Disconnected in Shutdown}
n _{Adaptive VOUT for Increased Efficiency}
n _{6V to 60V Input Voltage Range}
n _{±1.5% Accurate LED Current Matching}
n _{External Resistors Set LED Current for Each Channel}
n _{Requires No External Compensation}
n _{Programmable Switching Frequency (200kHz to 1MHz)}
n _{Synchronizable to External Clock}
n _{Open, Short LED Detection and Reporting}
n _{Programmable LED Thermal Derating and Reporting}
n _{Programmable Temperature Protection}
n _{5mm × 8mm Thermally Enhanced QFN Package with}
0.6mm High Voltage Pin Spacing
Applications
n _{LED Billboards and Signboards}
n _{Mono, Multi, Full Color LED Displays}
n _{Large Screen Display LED Backlighting}
n _{Automotive, Industrial and Medical Displays}
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.
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
programmed by placing a negative temperature coefficient
(NTC) resistor on the master control pin.
The LT3596 adaptively controls V_OUT in order to achieve
optimal efficiency. Other features include: 1.5% LED current
matching between channels, open LED reporting, shorted
LED pin protection and reporting, programmable LED cur-
rent and programmable temperature protection.
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.
All other trademarks are the property of their respective owners.
Typical Application
48V 1MHz Step-Down 8W, 100mA LED Driver (Eight White LEDs per Channel)
V_IN
48V
V_IN
10µF _270k
BIAS
EN/UVLO BOOST
SYNC
91k
SW
LT3596
SYNC
DA
RT
GND
33.2k
FB
PWM1
PWM2
PWM3
CTRL1
CTRL2
CTRL3
BIAS
PWM1
PWM2
PWM3
CTRL1
CTRL2
CTRL3
FAULT
90.9k
100k
FAULT
V_REF
10k
TSET
CTRLM
V_OUT
LED1
LED2
LED3
I_SET1
I_SET2
I_SET3
49.9k
100k
5V
4.7µF ^BIAS
100nF 100µH
100k
3.65k
20k 20k 20k
4.7µF
V_OUT
3696 TA01a
10,000:1 PWM Dimming at 100Hz
PWM
2V/DIV
I_LED
50mA/DIV
200ns/DIV
3596 TA01b
3596f