FAN5608_06 FAIRCHILD [Fairchild Semiconductor], FAN5608_06 Datasheet - Page 7

• Manufacturer Part Number: FAN5608_06
• Description: Serial / Parallel LED Driver with Current-Regulated, Step-Up DC/DC Converter
• Manufacturer: FAIRCHILD [Fairchild Semiconductor]

© 2006 Fairchild Semiconductor Corporation
FAN5608 Rev. 1.0.5 • 8/8/06
PWM Control
Notes:
5.
6.
7.
Figure 9. A is HIGH and B is PWM controlled; I
A Input (PWM)
B Input (PWM)
Proportionally select the duty cycle to achieve a typical LED current from 1mA to 4mA.
Maximum PWM frequency can be 30KHz.
Proportionally select the duty cycle to achieve a typical LED current from 1mA to 19mA.
A Input
B Input (PWM)
I LED
Figure 8. A is PWM controlled; B is LOW; I
Figure 10. A and B are PWM controlled; I
I LED
0mA
0mA
Duty Cycle
Duty Cycle
Duty Cycle
1KHz
30%
1KHz
1KHz
30%
30%
LED
LED
LED
(average) – s x 15mA +5mA, where s is the duty cycle
(average) – s x 20mA, where s is the duty cycle
(average) – s x 5mA, where s is the duty cycle
7
Duty Cycle
1KHz
70%
Duty Cycle
Duty Cycle
1KHz
1KHz
70%
70%
OFF
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OFF
(7)
(5)
(6)