High Efficiency Charge Pump White LED Driver
A8435
Performance Characteristics
Tests performed using application circuit shown in figure 1: dual wire control; and
VIN=3.6 V, EN1 = EN2 = VIN, CIN=C1=C2=COUT=1 μF, RSET=7.5 kΩ, TA=25°C (unless otherwise noted)
Efficiency versus Supply Voltage
Over Range of Dimming Levels, VIN Falling
100
90
Dimming Level
(mA)
80
70
60
50
4.75
9.8
17.6 (Full Brightness)
2.70
2.90
3.10
3.30
3.50
(V)
3.70
3.90
4.10
V
IN
Supply Current versus Supply Voltage
Over Range of Dimming Levels (mA)
120
100
80
60
40
20
0
VIN Rising
VIN Falling
17.6 mA
V
IN Rising
VIN Falling
9.8 mA
V
IN Rising
4.75 mA
V
IN Falling
2.70
2.90
3.10
3.30
3.50
3.70
3.90
4.10
V
(V)
IN
LED Current versus Supply Voltage
Matching Between LEDs <1% Over Range of VIN
20
19
18
17
16
15
14
13
12
11
10
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
V
(V)
IN
Allegro MicroSystems, Inc.
5
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 (508) 853-5000
www.allegromicro.com
ALLEGRO [ ALLEGRO MICROSYSTEMS ]
