CAT4137 Datasheet, PDF (4/16 Pages) Catalyst Semiconductor – CMOS Boost Converter - White LED Driver

CAT4137
TYPICAL CHARACTERISTICS
V_IN = 3.6V, C_IN = 1.0uF, C_OUT = 0.22µF, L = 22µH, with 3 LEDs at 20mA, T_AMB=25ºC, unless otherwise specified.
LED Current vs. Input Voltage (3 LEDs)
35
Rfb = 10Ω
30
25
Rfb = 15Ω
20
15
Rfb = 20Ω
10
5
LED Current Regulation
0.4
0.2
0.0
-0.2
0
2.0 2.5 3.0 3.5 4.0 4.5 5.0
INPUT VOLTAGE [V]
Efficiency across Supply Voltage (3 LEDs)
100
-0.4
2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5
INPUT VOLTAGE [V]
Efficiency across Load Current (3 LEDs)
100
15mA
90
VIN = 4.2V
90
80
20mA
70
80
VIN = 3.6V
70
60
2.0 2.5 3.0 3.5 4.0 4.5 5.0
INPUT VOLTAGE [V]
Efficiency across Supply Voltage (4 LEDs)
100
15mA
90
80
20mA
70
60
0
5 10 15 20 25 30
LED CURRENT [mA]
Efficiency across Load Current (4 LEDs)
100
VIN = 4.2V
90
VIN = 3.6V
80
70
60
2.0 2.5 3.0 3.5 4.0 4.5 5.0
INPUT VOLTAGE [V]
60
0
5 10 15 20 25 30
LED CURRENT [mA]
Doc. No. MD-5012 Rev. B
4
© Catalyst Semiconductor, Inc.
Characteristics subject to change without notice