Datasheet

9
LT1937
1937f
TYPICAL APPLICATIO S
U
Li-Ion to Two White LEDs Two LED Efficiency
V
IN
SW
LT1937
L
22µH
C
OUT
1µF
C
IN
1µF
C
IN
: TAIYO YUDEN JMK107BJ105
C
OUT
: AVX 0603ZD105
D: CENTRAL CMDSH2-3
L: MURATA LQH3C220
1937 TA05a
V
IN
3V TO 5V
SHDN
R1
2Ω
5k
90k
FB
D
V
DC
DIMMING
GND
LED CURRENT (mA)
0
EFFICIENCY (%)
78
80
82
40
1937 TA05a
76
74
70
10
20
30
72
86
84
V
IN
= 3.6V
V
IN
= 3V
V
IN
SW
LT1937
L
22µH
C
OUT
0.22µF
C
IN
1µF
C
IN
: TAIYO YUDEN JMK107BJ105
C
OUT
: AVX 0603YD224
D: CENTRAL CMDSH-3
L: MURATA LQH3C220
1937 TA01a
V
IN
3V TO 5V
SHDN
R1
4Ω
5k
90k
FB
D
V
DC
DIMMING
GND
LED CURRENT (mA)
0
60
EFFICIENCY (%)
65
70
75
80
85
90
V
IN
= 3V
5101520
1937 TA01b
V
IN
= 3.6V
Li-Ion to Three White LEDs Three LED Efficiency