Datasheet

LT3956
17
3956f
Typical applicaTions
Buck-Boost Mode LED Driver
LT3956
L1
68µH
GNDV
C
INTV
CC
EN/UVLO
FB
PGND
V
REF
ISP
1M
0.1µF
V
IN
9V TO
45V
V
IN
V
IN
V
OUT
L1: COILCRAFT MSS1038-683
D1: ON SEMICONDUCTOR MBRS3100T3
M1: ZETEX ZXM6IP03F
Q1: ZETEX FMMT493
187k
35.7k
300kHz
3.4k
10nF
4.7µF
CTRL
750Ω
1k
Q1
M1
680mΩ
619k
10k
D1
4.7µF
35V
3956 TA03a
VMODE
PWM
SS
RT
ISN
PWMOUT
C1
4.7µF
1µF
100V
24V
LED STRING
350mA
100k
INTV
CC
INTV
CC
V
IN
SW
Efficiency vs V
IN
V
IN
(V)
0 10
80
EFFICIENCY (%)
84
88
92
96
100
30
40
3956 TA03b
20
50
28V
IN
/0V to 28V SEPIC SuperCap Charger with Input Current Limit
V
IN
LT3956
L1A
33µH
1:1
GND
V
C
INTV
CC
INTV
CC
EN/UVLO
SW
V
REF
ISP
10k
1µF
10nF
V
IN
28V
≤ 1.2A
V
OUT
0V TO 28V
L1: WÜRTH ELEKTRONIK 744871330
D1: ON SEMI MBRS36OT
Q1: MMBTA42
C1, C3, C4: TAIYO-YUDEN GMK 3I6BJ106
28.7k
375kHz
C3
10µF
PGND
L1B
C2
4.7µF
CTRL
30.1k
1M
D1
C4
10µF
3956 TA04a
VMODE
PWMOUT
PWM
SS
RT
ISN
FB
40.2k
1M
2k
59k
25k
536k
14k
C1
10µF
Q1
200mΩ
Input and Output Current
vs Output Voltage
V
OUT
(V)
0
0
INPUT/OUTPUT CURRENT (A)
0.5
1.0
1.5
2.0
3.0
5
10 15 20
3956 TA04b
25 30
2.5
INPUT
OUTPUT