LT3590 Datasheet, PDF (1/16 Pages) Linear Technology – 48V Buck Mode LED Driver in SC70 and 2mm x 2mm DFN

FEATURES
■ _{4.5V to 55V Input Voltage Range}
■ _{Up to 50mA LED Current}
■ _{80mA, 55V Switch}
■ _{Internal Schottky Diode}
■ _{15μA Supply Current in Shutdown}
■ _{500μA Supply Current Operating, Not Switching}
■ _{Switching Frequency: 850kHz}
■ _{200mV Feedback Voltage with ±5% Accuracy}
■ _{CTRL Input Performs Dimming and Shutdown}
■ _{91% Efficiency (10 LEDs, 50mA)}
■ _{Requires Only 1μF Output Capacitor}
■ _{8-Lead SC70 Package}
■ _{6-Lead 2mm × 2mm DFN Package}
APPLICATIONS
■ _{LED Fixed Signage}
■ _{Traffic Signs}
■ _{Neon Sign Replacement}
LT3590
48V Buck Mode
LED Driver in SC70
and 2mm x 2mm DFN
DESCRIPTION
The LT^®3590 is a fixed frequency buck mode converter
specifically designed to drive up to 10 LEDs in series from
a 48V DC source. Series connection of the LEDs provides
identical LED currents of up to 50mA, resulting in uniform
brightness and eliminating the need for ballast resistors.
A fixed frequency, current mode architecture results in
stable operation over a wide range of input voltage and
output voltage.
The high switching frequency of 850kHz permits the use
of tiny, low profile inductors and capacitors. A single pin
performs both shutdown and accurate LED dimming
control. The power switch, Schottky diode and control
circuitry are all contained inside a space saving SC70
package or 2mm × 2mm DFN package to allow a small
converter footprint and lower parts cost.
, LT, LTC and LTM are registered trademarks of Linear Technology Corporation.
All other trademarks are the property of their respective owners.
TYPICAL APPLICATION
V_IN
48V
CONTROL
Buck Mode Driver for Ten White LEDs
1μF
50mA
4Ω
1μF
0.1μF
V_IN
LED
CTRL
LT3590
VREG
SW
GND
470μH
3590 TA01a
Conversion Efficiency
100
90
80
70
60
50
40
0
10
20
30
40
50
LED CURRENT (mA)
3590 TA01b
3590f
1