AP1521
White LED Step-Up Converter
Typical Performance Characteristics (Continued)
Li-lon to Five White LEDs
V
IN
3.3V To 5V
L
22uH
C
IN
1uF
V
IN
SHDN
GND
C
IN
: TAIYO YUDEN JMK107BJ105
C
OUT
: AVX 0603YD224
D: CENTRAL CMDSH-3
L: MURATA LQH3C220
D
V
DC
Dimming
SW
90k
5k
R1
6.8Ω
C
OUT
0.22uF
Efficiency (%)
AP1521
FB
84
81
78
75
72
69
66
63
60
57
AP1521 Efficiency(%) v.s. LED
Current (mA)
Vin=5V
Vin=3.6V
Vin=4.2V
0
10
LED Current (mA)
20
30
40
50
Li-lon to Six White LEDs
V
IN
3.6V To 5V
L
22uH
C
IN
1uF
V
IN
SHDN
GND
C
IN
: TAIYO YUDEN JMK107BJ105
C
OUT
: AVX 0603YD224
D: CENTRAL CMDSH-3
L: MURATA LQH3C220
D
V
DC
Dimming
SW
90k
5k
R1
6.8Ω
C
OUT
0.22uF
Efficiency (%)
AP1521
FB
84
81
78
75
72
69
66
63
60
57
AP1521 Efficiency(%) v.s. LED
Current (mA)
Vin=5V
Vin=4.2V
Vin=3.6V
0
10
LED Current (mA)
20
30
40
50
Step up DC-DC Regulator
V
IN
2.5V~3.3V
L
22uH
C
IN
1uF
V
IN
SHDN
GND
C
IN
: TAIYO YUDEN JMK107BJ105
C
OUT
: AVX 0603YD224
D: CENTRAL CMDSH-3
L: MURATA LQH3C220
D
V
OUT
4.8V
15K
C
OUT
0.22uF
90
85
80
75
70
65
60
AP1521 Efficiency(%) v.s. Load
Current (mA)@Vout=4.8V
Vin=3.3V
Vin=2.5V
SW
FB
1K
AP1521
Efficiency (%)
0
10
Load Current (mA)
20
30
40
50
Anachip Corp.
www.anachip.com.tw
7/8
Rev. 0.1
Apr. 27, 2004
ANACHIP [ ANACHIP CORP ]
