Preliminary
RT9272
Typical Operating Characteristics
Efficiency vs. Input Voltage
Quiescent Current vs. VCC
89
88
87
86
85
84
83
82
81
80
79
78
0.25
0.24
0.23
0.22
0.21
0.2
L = 4.7uH, DCR = 0.15Ω
VFB = 1V
2LEDs
4LEDs
0.19
0.18
0.17
0.16
0.15
2.7 2.9 3.1 3.3 3.5 3.7 3.9 4.1 4.3 4.5
Input Voltage (V)
2.7 2.9 3.1 3.3 3.5 3.7 3.9 4.1 4.3 4.5
VCC (V)
Supply Current vs. VCC
VFB vs. VCC
2.1
1.9
1.7
1.5
1.3
1.1
0.9
0.7
0.5
0.33
0.32
0.31
0.3
VFB = 0V
0.29
0.28
0.27
2.7 2.9 3.1 3.3 3.5 3.7 3.9 4.1 4.3 4.5
VCC (V)
2.7 2.9 3.1 3.3 3.5 3.7 3.9 4.1 4.3 4.5
VCC (V)
VFB vs. Temperature
EN Pin Voltage vs. Input Voltage
0.315
0.3125
0.31
1.6
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0.0
VIH
VIL
0.3075
0.305
0.3025
0.3
0.2975
0.295
-40 -30 -20 -10
0
10 20 30 40 50 60 70 80 90
2.7 2.9 3.1 3.3 3.5 3.7 3.9 4.1 4.3 4.5
Input Voltage (V)
Temperature (°C)
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DS9272-09 August 2007
RICHTEK [ RICHTEK TECHNOLOGY CORPORATION ]
