CAT37 CATALYST [Catalyst Semiconductor], CAT37 Datasheet - Page 9

• Manufacturer Part Number: CAT37
• Description: CMOS White LED Driver Boost Converter
• Manufacturer: CATALYST [Catalyst Semiconductor]

3 V to 4.2 V
3 V to 4.2 V
Two LEDs with DC Level Dimming Control
The application diagrams are shown for the SOT23 pin numbers.
Three LEDs with DC Level Dimming Control
Four LEDs with PWM Dimming Control
3 V to 4.2 V
VIN
VIN
VIN
4
4
4
SHDN
SHDN
SHDN
5
VIN
5
VIN
5
VIN
CAT37
CAT37
CAT37
GND
GND
GND
SW
SW
SW
FB
1
FB
2
1
1
FB
2
2
18k
3
18k
10k
18k
3
3
Dimming
Dimming
PWM
V DC
V DC
D1
D1
D1
1k
1k
1k
15mA
15mA
15mA
9
Efficiency - Two LEDs
Efficiency - Three LEDs
Efficiency - Four LEDs
90
85
80
75
70
65
60
90
85
80
75
70
65
60
90
85
80
75
70
65
60
0
0
0
5
5
5
LED CURRENT [mA]
LED CURRENT [mA]
LED CURRENT [mA]
10
10
10
VIN = 3.6V
VIN = 3.0V
VIN=3.0V
VIN=3.6V
VIN = 3.6V
VIN = 3.0V
VIN=3.6V
VIN = 3.6V
15
VIN = 3.0V
15
VIN = 3.6V
VIN = 3.0V
15
VIN=3.0V
20
20
20
Doc No. 5005, Rev. R
25
25
25
30
30
30