FAN5602_07 FAIRCHILD [Fairchild Semiconductor], FAN5602_07 Datasheet - Page 12

• Manufacturer Part Number: FAN5602_07
• Description: Universal (Step-Up/Step-Down) Charge Pump Regulated DC/DC Converter
• Manufacturer: FAIRCHILD [Fairchild Semiconductor]

FAN5602 Rev. 1.5.0
© 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 28. Circuit for Backlighting / Flash Application
10F
1F
V
IN
FAN5602
V
OUT
1F
10F
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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
50
FOL216CIW
50
50
FLASH
FOL625CIW
www.fairchildsemi.com
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