FAN5602 Fairchild Semiconductor, FAN5602 Datasheet - Page 11

• Manufacturer Part Number: FAN5602
• Description: The FAN5602 is a universal switched capacitor DC/DC converter capable of step-up or step-down operation
• Manufacturer: Fairchild Semiconductor

FAN5602 Rev. 1.5.3
© 2005 Fairchild Semiconductor Corporation
Application Information
Using the FAN5602 to Drive LCD Backlighting
The FAN5602 4.5V option is ideal for driving the back-
lighting and flash LEDs for portable devices. One
FAN5602 device can supply the roughly 150mA needed
to power both the backlight and the flash LEDs. Even
though drawing this much current from the FAN5602
drives the part out of the 3% output regulation, it is not a
3.2 to 4.2V
BATTERY
Figure 25. Circuit for Backlighting / Flash Application
10µF
1µF
V
IN
FAN5602
V
OUT
1µF
10µF
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problem. The backlight and flash LEDs still produce opti-
mal brightness at the reduced regulation. When building
this circuit, use ceramic capacitors with low ESR. All
capacitors should be placed as close as possible to the
FAN5602 in the PCB layout.
BACKLIGHT
50
FOL216CIW
50
50
FLASH
50
FOL625CIW
www.fairchildsemi.com
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