W-6237 Datasheet, PDF (6/13 Pages) Copal Electronics – High Voltage CMOS Boost

W-6237
TYPICAL CHARACTERISTICS
(V_IN = 3.6 V, C_IN = 4.7 F, C_OUT = 0.22 F, L = 33 H with 8 LEDs at 20 mA, T_AMB = 25$C, unless otherwise specified.)
35
1.0
30
R_FB = 10
25
0.5
R_FB = 15
20
R_FB = 20
0
15
10
5
0
2.5
3.0
3.5
4.0
4.5
5.0
INPUT VOLTAGE (V)
Figure 10. LED Current vs. Input Voltage
(8 LEDs)
90
ï0.5
ï1.0
3.0 3.3
3.6
3.9
4.2
4.5 4.8
INPUT VOLTAGE (V)
Figure 11. LED Current Regulation (20 mA)
90
85
VIN = 4.2 V
85
20 mA
15 mA
80
VIN = 3.6 V
80
75
8 LEDs
70
VOUT ~ 27 V at 20 mA
L = 33 H
65
5
10
15
20
25
30
LED CURRENT (mA)
Figure 12. 8 LED Efficiency vs. Load Current
75
8 LEDs
70 VOUT ~ 27 V at 20 mA
L = 33 H
65
3.0
3.5
4.0
4.5
5.0
INPUT VOLTAGE (V)
Figure 13. 8 LED Efficiency vs. Input Voltage
90
90
VIN = 4.2 V
VIN = 4.2 V
85
85
VIN = 3.6 V
VIN = 3.6 V
80
80
75
7 LEDs
70
VOUT ~ 23 V at 20 mA
L = 33 H
65
5
10
15
20
25
30
LED CURRENT (mA)
Figure 14. 7 LED Efficiency vs. Load Current
75
6 LEDs
70
VOUT ~ 20 V at 20 mA
L = 33 H
65
5
10
15
20
25
30
LED CURRENT (mA)
Figure 15. 6 LED Efficiency vs. Load Current
6