4

POWER SUPPLY DATA

For the standard evaluation board (4x20mA series white LEDs application), in which the output

voltage is around 15V and output current is 20mA, the power supply data is provided in Fig 1. to

Fig. 4. The white LEDs used here were from LUMEX (Part Number: SML-LX2832UWC-TR).

.

0

4

8

12

16

20

0

2040

6080

100

PWM Duty Cycle (%)

50

55

60

65

70

75

80

85

90

2.7

3

3.3

3.6

3.9

4.2

Input Voltage (V)

Fig. 1 Efficiency vs Input VoltageFig. 2 Average Io vs SHDN duty cycle

Fig. 3 Typical Switching Waveform

(0.5A/DIV)

(AC)

(AC)