Datasheet

CAT3637
http://onsemi.com
5
TYPICAL PERFORMANCE CHARACTERISTICS
(V
IN
= 3.6 V, I
OUT
= 120 mA (6 LEDs at 20 mA), C
IN
= C
OUT
= C
1
= C
2
= 1 mF, T
AMB
= 25°C unless otherwise specified.)
Figure 3. Efficiency vs. Input Voltage Figure 4. Efficiency vs. Li−Ion Voltage
INPUT VOLTAGE (V) INPUT VOLTAGE (V)
2.02.53.03.54.04.5
40
50
60
70
80
90
100
3.03.23.43.63.84.04.2
40
50
60
70
80
90
100
Figure 5. LED Current Change vs. Input
Voltage
Figure 6. LED Current Change vs.
Temperature
INPUT VOLTAGE (V) TEMPERATURE (°C)
2.53.03.54.04.55.05.5
−10
−8
−4
−2
2
4
8
10
806040200−20−40
−10
−8
−6
−2
0
4
8
10
Figure 7. Quiescent Current vs. Input Voltage
INPUT VOLTAGE (V)
2.5 2.03.03.54.04.55.05.5
0
1
2
3
4
5
6
EFFICIENCY (%) EFFICIENCY (%)
LED CURRENT VARIATION (%) LED CURRENT VARIATION (%)
QUIESCENT CURRENT (mA)
1x
1.33x
1.5x
2x
Traditional 1.5x
Charge Pump
V
F
= 3.3 V
V
F
= 3.3 V
V
F
= 3.0 V
V
F
= 3.3 V
−6
0
6
−4
2
6
V
F
= 3.3 V