SGM3124 Datasheet, PDF (7/17 Pages) SG Micro Corp – White LED Charge Pump Current Source with PWM Brightness Control

SGM3124
White LED Charge Pump Current
Source with PWM Brightness Control
TYPICAL PERFORMANCE CHARACTERISTICS
Efficiency vs. Input Voltage
90
5mA
80
10mA
EN1 = EN2 = 1
25mA
70
60
20mA
15mA
50
40 ^{The curve with higher efficiency is for Input}
voltage from high to low
30
2.5
3
3.5
4
4.5
5
5.5
Input Voltage (V)
Figure 1
1020
1000
Switching Frequency vs. Temperature
V_IN = 3.6V
980
960
940
920
900
-55 -35 -15 5 25 45 65 85
Temperature (℃)
Figure 3
LED Current Regulation vs. Input Voltage
25.5
25.3
25.1
24.9
24.7
24.5
3.2 3.6
4
4.4
4.8
5.2 ^5.5
Input Voltage (V)
Figure 5
D1 LED Current vs Duty Cycle
25
EN1 = EN2 = 1
20 ^I LED ^{max set to 20mA}
15
10
f = 32kHz
5
f = 1kHz
0
0 10 20 30 40 50 60 70 80 90 100
Duty Cycle (%)
Figure 2
Quiescent Current vs. Input Voltage
3
2.5
T_A = 25℃
2
1.5
1
0.5
0
2.7 3.1 3.5 3.9 4.3 4.7 5.1 5.5
Input Voltage (V)
Figure 4
Maximum Output Current vs. Input Voltage
180
160
140
120
100
80
V_LED = 3.1V
60
T_A = 25℃
40
2.7
3.2
3.7
4.2
4.7
5.2 5.5
Input Voltage (V)
Figure 6
SG Micro Corp
www.sg-micro.com
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