L1937 Datasheet, PDF (6/7 Pages) Unisonic Technologies – WHITE LED STEP-UP CONVERTER

UTC L1937
LINEAR INTEGRATED CIRCUIT
TYPICAL PERFORMANCE CHARACTERISTICS

2.2
2.0
1.8
1.6
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0
0
Quiescent Current
-50Ċ
25Ċ
100Ċ
2
4
6
8
10
VIN (V)
SHDN Pin Bias Current
400
350
300
SHDN=10V
250
200
150
SHDN=3.6V
SHDN=3V
100
50
SHDN=2.7V
0
-50 -25
0
25
50
75 100
TEMPERATURE (Ċ)
Switching Frequency
1.4
1.2
1.0
0.8
0.6
0.4
0.2
Feedback Bias Current
60
50
40
30
20
10
0
-50 -25
0
25
50
75
100
TEMPERATURE (Ċ)
0
-50 -25
0
25
50
75
100
TEMPERATURE (Ċ)
Efficiency vs Temperature
85
VIN=3.6V
3 LEDs
ILED=20mA
84
83
ILED=15mA
82
ILED=10mA
81
80
-50
0
50
100
TEMPERATURE (Ċ)


350
300
250
200
150
100
50
0
0
Current Limit vs Duty Cycle
20
40
60
80
DUTY CYCLE (%)
100


UTC UNISONIC TECHNOLOGIES CO., LTD. 6
QW-R103-021,A