LT3475/LT3475-1
20
3475fb
Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408) 432-1900
●
FAX: (408) 434-0507
●
www.linear.com
© LINEAR TECHNOLOGY CORPORATION 2006
LT 1007 REV B • PRINTED IN USA
RELATED PARTS
PART NUMBER DESCRIPTION COMMENTS
LT1618 Constant-Current, 1.4MHz, 1.5A Boost
Converter
V
IN(MIN)
= 1.6V, V
IN(MAX)
= 18V, V
OUT(MAX)
= 35V, Analog/PWM, I
SD
< 1μA,
MS10 Package
LT3466 Dual Full Function Step-Up LED Driver Drivers Up to 20 LEDs, V
IN
: 2.7V to 24V, V
OUT(MAX)
= 40V, DFN, TSSOP16E Packages
LT3474 36V, 1A (I
LED
), 2MHz Step-Down
LED Driver
V
IN(MIN)
= 4V, V
IN(MAX)
= 36V, 400:1 True Color PWM, I
SD
< 1μA,
TSSOP16E Package
LT3477 42V, 3A, 3.5MHz Boost, Buck-Boost,
Buck LED Driver
V
IN(MIN)
= 2.5V, V
IN(MAX)
= 25V, V
OUT(MAX)
= 40V, Analog/PWM, I
SD
< 1μA,
QFN, TSSOP20E Packages
LT3479 3A, Full-Featured DC/DC Converter with
Soft-Start and Inrush Current Protection
V
IN(MIN)
= 2.5V, V
IN(MAX)
= 24V, V
OUT(MAX)
= 40V, Analog/PWM, I
SD
< 1μA,
DFN, TSSOP Packages
LT3846 Dual 1.3A, 2MHz, LED Driver V
IN
: 2.5V to 24V, V
OUT(MAX)
= 36V, 1000:1 True Color PWM
TM
Dimmin,
DFN, TSSOP16E Packages
BOOST1 BOOST2
SW1 SW2
OUT1 OUT2
LED1
12V TO 18V LED VOLTAGE 12V TO 18V LED VOLTAGE
LED2
V
C1
V
C2
REF R
T
V
ADJ1
V
ADJ2
GND
LT3475-1
V
IN
V
IN
21V TO 36V
SHDN
C2
0.22μF
16V
C1
4.7μF
50V
L1
33μH
R1
1k
R6
100k
R4
10k
R7
100k
R5
10k
L2
33μH
D3
D6
D4
R2
1k
C3
0.22μF
16V
R3
24.3k
C4
2.2μF
25V
C5
2.2μF
25V
D7
Q1
D2D1
D5
C7
0.1μF
C6
0.1μF
3475 TA08
1.5A LED
CURRENT*
1.5A LED
CURRENT*
f
SW
= 600kHz
D8
Q2
D1, D4: 7.5V ZENER DIODE
D2, D3: MMSD4148
D5, D6: B240A
D7, D8: 22V ZENER DIODE
R1, R2: USE 0.5W RESISTOR OF TWO 2k 0.25W RESISTORS IN PARALLEL
Q1, Q2: MMBT3904
C1 TO C5: X5R or X7R
*DERATE LED CURRENT AT ELEVATED AMBIENT TEMPERATURES TO MAINTAIN LT3475-1 JUNCTION TEMPERATURE BELOW 125 °C.
Dual Step-Down 1.5A LED Driver with Four Series Connected LED Output
TYPICAL APPLICATION