CAT32

http://onsemi.com

9

TYPICAL APPLICATION CIRCUITS

(The application diagrams below are shown for the TSOT−23 packages.)

Figure 16. Two LEDs with DC Level Dimming Control

2.5 V DC

DIMMING

CONTROL

15 mA

4

1.50 kW

60.40 kW

6.8 mH

2

3

1

6

5

SW

VIN

RSET

D1

C2

2.2 mF

C1

4.7 mF

VIN

CAT32

LED

GND

2.5 V DC

DIMMING

CONTROL

15 mA

4

1.50 kW

60.40 kW

6.8 mH

2

3

1

6

5

SW

VIN

RSET

D1

C2

1 mF

C1

4.7 mF

VIN

CAT32

LED

GND

Figure 17. Three LEDs with DC Level Dimming Control

15 mA

4

1.50 kW

6.8 mH

2

3

1

6

5

SW

VIN

RSET

D1

C2

1 mF

C1

4.7 mF

VIN

PWM

DIMMING

CONTROL

CAT32

LED

GND

Figure 18. Efficiency − Three LEDs

LED CURRENT (mA)

20

15

10

5

0

60

65

70

75

80

85

LED CURRENT (mA)

Figure 19. Four LEDs with PWM Dimming Control

Figure 20. Efficiency − Four LEDs

SHDN

20

15

10

5

0

60

65

70

75

80

85

SHDN

SHDN