
Micrel, Inc.
Typical Characteristics
MIC3287
White LED Efficiency
V IN =3.6V
V IN =4.2V
85
80
75 V IN =3.2V
70
65
3 Series
85
80
75
70
65
4 Series
White LED Efficiency
V IN =3.6V
V IN =3.2V
V IN =4.2V
12
10
8
6
Enable Pin Current
vs. Temperature
V EN =5V
V EN =3.3V
V EN =2.5V
2
2
-40 -25 -10 5 20 35 50 65 80
60
55
50
45
L = 10μH
C OUT = 0.22μF
4 6 8 10 12 14 1 6 1 8 20
WHITE LED CURRENT (mA)
60
55
50
45
L = 10μH
C OUT = 0.22μF
4 6 8 10 12 14 1 6 1 8 20
WHITE LED CURRENT (mA)
4
2
0
V EN =1.8V
TEMPERATURE (°C)
1.5
1.4
1.3
1.2
Frequency
vs. Temperature
V IN =4.2V
V IN =3.6V
V IN =3.2V
260
256
252
248
Feedback Voltage
vs. Temperature
V IN =3.6V
254
253
252
251
250
Feedback Voltage
vs. Input Voltage
-40 -25 -10 5 20 35 50 65 80
-40 -25 -10 5 20 35 50 65 80
2.8 3.2 3.6 4.0 4.4 4.8 5.2 5.6
1.1
1.0
TEMPERATURE (°C)
244
240
TEMPERATURE (°C)
249
248
INPUT VOLTAGE (V)
0.003
Shutdown Current
vs. Input Voltage
2.5
Quiescent Current
vs. Input Voltage
900
Curremt Limit
vs. Temperature
2.4
850
0.002
2.3
2.2
2.1
800
750
700
650
V IN =3.6V
2.8 3.2 3.6 4.0 4.4 4.8 5.2 5.6
2.8 3.2 3.6 4.0 4.4 4.8 5.2 5.6
-40 -25 -10 5 20 35 50 65 80
2.8 3.2 3.6 4.0 4.4 4.8 5.2 5.6
0.001
840
820
800
780
760
740
720
April 2010
INPUT VOLTAGE (V)
Current Limit
vs. Input Voltage
INPUT VOLTAGE (V)
2.0
INPUT VOLTAGE (V)
4
600
TEMPERATURE (°C)
M9999-042910