
EL7513
Typical Performance Curves (Continued)
All performance curves and waveforms are taken with C 1 = 4.7μF, C 2 = 1μF, C 3 = 0.1μF, L = 33μF, V IN = 3.3V, V CNTL = 1V, R 1 = 5 Ω , 4 LEDs in a
series; unless otherwise specified.
L
BAT54HT1
V IN
4.7μF
33μH
1μF
90
2 LEGS OF 4 LEDs IN A SERIES
8
VIN
LX
4
85
V IN = 4.2V
VOUT
CS
3
7
80
V IN = 2.7V
V CTRL
2
1
CNTL PGND
COMP SGND
5
6
5 Ω
5 Ω
75
70
L =SUMIDA CMD13D13-33μH
0.1μF
10
20
30
40
50
60
I O (mA)
FIGURE 10A. 2 LEGS OF 4 LEDs IN A SERIES
FIGURE 10.
FIGURE 10B. EFFICIENCY vs I O
V IN
L
15μH
BAT54HT1
4.7μF
1μF
95
3 LEGS OF 2 LEDs IN A SERIES
8
VIN
LX
VOUT
4
3
90
85
V IN = 4.2V
V IN = 2.7V
V CTRL
2
CS
CNTL PGND
7
5
5 Ω
5 Ω
5 Ω
80
75
1
COMP SGND
6
70
L = SUMIDA CMD13D13-15μH
0.1μF
15
35
55
I O (mA)
75
95
FIGURE 11A. 3 LEGS OF 2 LEDs IN A SERIES
FIGURE 11.
FIGURE 11B. EFFICIENCY vs I O
V IN
4.7μF
L
15μH
BAT54HT1
1μF
95
3 LEGS OF 3 LEDs IN A SERIES
8
VIN
LX
VOUT
4
3
90
85
V IN =4.2V
V IN =2.7V
CS
7
80
V CTRL
2
CNTL PGND
5
5 Ω
5 Ω
5 Ω
75
1
COMP SGND
6
70
L=SUMIDA CMD13D13-15μH
0.1μF
15
35
55
75
95
I O (mA)
FIGURE 12A. 3 LEGS OF 3 LEDs IN A SERIES
7
FIGURE 12.
FIGURE 12B. EFFICIENCY vs I O
FN7112.5
December 22, 2008