LM1937
TYPICAL APPLICATIONS
L
22 H
C
IN
1μF
D
C
OUT
1μF
86
84
82
V
IN
= 3.6V
V
IN
3V TO 5V
EFFICIENCY (%)
V
DC
DIMMING
V
IN
= 3V
80
78
76
74
72
V
IN
LM1937
SHDN
GND
SW
90k
5k
FB
R1
2Ω
1937 TA05a
C
IN
: TAIYO YUDEN JMK107BJ105
C
OUT
: AVX 0603ZD105
D: CENTRAL CMDSH2-3
L: MURATA LQH3C220
70
0
10
20
LED CURRENT (mA)
30
40
1937 TA05a
Li-Ion to Two White LEDs
Two LED Efficiency
TYPICAL APPLICATIO
V
IN
3V TO 5V
L
22 H
C
IN
1μF
D
C
OUT
0.22μF
EFFICIENCY (%)
90
85
80
V
IN
= 3V
75
70
65
60
0
5
10
15
LED CURRENT (mA)
20
1937 TA01b
V
DC
DIMMING
V
IN
LM1937
SHDN
GND
SW
90k
5k
FB
R1
4Ω
1937 TA01a
V
IN
= 3.6V
C
IN
: TAIYO YUDEN JMK107BJ105
C
OUT
: AVX 0603YD224
D: CENTRAL CMDSH-3
L: MURATA LQH3C220
Li-Ion to Three White LEDs
Three LED Efficiency
Four LED Efficiency
V
IN
3V TO 5V
L
22 H
C
IN
1μF
D
C
OUT
0.22μF
EFFICIENCY (%)
85
80
V
IN
= 3V
75
V
IN
= 3.6V
V
DC
DIMMING
V
IN
SHDN
GND
SW
LM1937
FB
R1
4Ω
90k
5k
70
C
IN
: TAIYO YUDEN JMK107BJ105
C
OUT
: AVX 0603YD224
D: CENTRAL CMDSH-3
L: MURATA LQH3C220
1937 TA02a
60
0
15
5
10
LOAD CURRENT (mA)
20
1937 TA02b
Li-Ion to Four White LEDs
Four LED Efficiency
RELATED PARTS
5
WWW.HN-ELEC.COM
U
Li-Ion to Four W
HN [ NANJING HONANO ELECTRONIC CO., LTD. ]
