CAT4238
TYPICAL CHARACTERISTICS
V
IN
= 3.6V, C
IN
= 4.7μF, C
OUT
= 0.22µF, L = 47µH with 10 LEDs at 20mA, T
AMB
= 25ºC, unless otherwise specified.
LED Current vs. Input Voltage
R1 = 10Ω
VOUT = 33.8V
R1 = 15Ω
VOUT = 33V
LED Current Regulation (10mA)
LED CURRENT VARIATION [%] .
1.0
40
35
LED CURRENT [mA]
30
25
20
15
10
5
0
3.0
3.5
0.5
0.0
R1 = 20Ω
VOUT = 32.5V
-0.5
10 LEDs @ 10mA
-1.0
3.0
3.5
4.0
4.5
5.0
5.5
INPUT VOLTAGE [V]
4.0
4.5
5.0
5.5
INPUT VOLTAGE [V]
Efficiency vs. Load Current (10 LEDs)
100
Efficiency vs. Input Voltage (10 LEDs)
100
VOUT = 32.5V
10 LEDs @ 15mA
80
VIN = 3.6V
70
EFFICIENCY [%]
EFFICIENCY [%]
90
VIN = 5V
90
80
VOUT = 33V
10 LEDs @ 20mA
70
60
5
10
15
20
25
30
LED CURRENT [mA]
60
3.0
3.5
4.0 4.5
5.0
INPUT VOLTAGE [V]
5.5
Power-up with 10 LEDs at 20mA
Switch ON Resistance vs. Input Voltage
2.0
SWITCH RESISTANCE [Ω]
1.5
1.0
0.5
0.0
3.0
3.5
4.0
4.5
5.0
5.5
INPUT VOLTAGE [V]
Doc. No. MD-5019 Rev. E
6
© 2008 SCILLC. All rights reserved.
Characteristics subject to change without notice
ONSEMI [ ON SEMICONDUCTOR ]
