LT3595
16 Channel
Buck Mode LED Driver
FEATURES
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DESCRIPTION
The LT
®
3595 is a high performance LED Driver designed
to drive sixteen independent channels of up to 10 LEDs
at currents up to 50mA. Series connection of the LEDs
provides identical LED currents resulting in uniform bright-
ness. Power switches, Schottky diodes, and compensation
components are all internal, providing a small converter
footprint and lower component cost. The high 2MHz
switching frequency permits the use of tiny, low profile
inductors and capacitors. A fixed frequency, current mode
architecture results in stable operation over a wide range
of supply and output voltage.
A single external resistor sets the LED current for all sixteen
channels, and dimming is then controlled for each channel
by pulse width modulating the individual PWM pins. Rela-
tive current matching among the sixteen drivers is 8% and
the PWM dimming range is 5000:1. The part is available
in a 5mm
×
9mm
×
0.75mm 56-pin QFN package.
, LT, LTC and LTM are registered trademarks of Linear Technology Corporation.
True Color PWM is a trademark of Linear Technology Corporation. All other trademarks are
the property of their respective owners.
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
TM
Dimming Range
LEDs Disconnected in Shutdown
Internal Schottky Diodes
Low Quiescent Current
2MHz Switching Frequency
R
SET
Pin Sets Master LED Current
Typical Efficiency: 92%
Open LED Detection and Thermal Protection
56-Pin 5mm
×
9mm
×
0.75mm QFN Package
APPLICATIONS
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LED Video Billboards
LCD Televisions
Stadium and Advertising Displays
TYPICAL APPLICATION
16-Channel LED Driver (Three LEDs per Channel), 20mA Current
V
IN
15V TO
45V
10μF
0.47μF
0.47μF
0.47μF
0.47μF
0.47μF
0.47μF
0.47μF
0.47μF
V
PWM
5V/DIV
5000:1 PWM
Dimming at 100Hz
100μH
100μH
100μH
100μH
100μH
100μH
100μH
V
CC
100k
100μH
LED
BRIGHTNESS
CONTROL
V
CC
3V TO
5.5V
10μF
100μH
100μH
100μH
100μH
100μH
100μH
100μH
0.47μF
0.47μF
0.47μF
0.47μF
0.47μF
0.47μF
0.47μF
100μH
0.47μF
3595 TA01
75.0k
L1 SW1
OPENLED
PWM1
PWM2
PWM3
PWM4
PWM5
PWM6
PWM7
PWM8
SHDN
V
CC
L16 SW16
L2
SW2
SW3
L3
SW4
L4
L5
SW5
L6
SW6
SW7
L7
SW8
L8
I
SW
20mA/DIV
LT3595
L15 SW15 V
IN
SW14 L14
SW13
L13
L12
SW12 L11 SW11 V
IN
SW10 L10
PWM9
PWM10
PWM11
PWM12
PWM13
PWM14
PWM15
PWM16
GND
R
SET
SW9 L9
LED
BRIGHT-
NESS
CONTROL
I
LED
10mA/DIV
400ns/DIV
V
IN
= 15V
3 LEDS AT 20mA
T = 10ms
T
ON
= 2μs
3595 TA01b
3595f
1
LINER [ LINEAR TECHNOLOGY ]
