Datasheet

LT3519/LT3519-1/LT3519-2
14
3519fa
TYPICAL APPLICATIONS
Buck-Boost Mode 150mA LED Driver
Waveform for Open LED Effi ciency vs V
IN
V
IN
SW
L1
47μH
R
SENSE
1.65Ω
V
OUT
16V LED 150mA
V
REF
PWM
CTRL
357k
24.3k
3519 TA03a
10k
CATHODE
SHDN/UVLO
ISN
ISP
FB
OPENLED
LT3519
GND
1M
1M
210k
100k
243k
V
IN
6V TO 24V
C1
1μF
ANODE
C2
1μF
C3
4.7μF
Q1
C1: TDK C3216X7R1H105K
C2: TDK C3216X7R1H105K
C3: TDK C3216X7R1E475K
L1: COILTRONICS DR73-470-R
Q1: DIODES FMMT555 PNP
NOTE:
V
IN
= 8.2V RISING TURN ON
V
IN
= 6.2V FALLING UVLO
V
IN
> 7V FULL LED CURRENT AND FOLDBACK BELOW
V
OUT
– V
IN
18.5V OVERVOLTAGE PROTECTION
V
OUT
10V/DIV
I
LED
0.1A/DIV
OPENLED
10V/DIV
50μs/DIV
3519 TA03b
V
IN
= 12V
V
IN
(V)
6
EFFICIENCY (%)
72
74
76
15
21
3519 TA03c
70
68
66
912 18
78
80
82
24