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3. BB Circuit Technical brief
3.10 keypad back-light illumination
3.10.1 Number keypad back-light illumination
There are 2 snow white color LEDs on Key for keypad illumination. Keypad Back-light is controlled by SM-
Power3 Flash LED port which has constant current control function. The whole configuration of the SM-
POWER3 Flash LED drivers is shown in below Figure.
[Figure 3.10.1-2] Number key back-light LED circuit diagram
LGE Internal Use Only
[Figure 3.10.1-1] LED driver in the SM-POWER3
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GM310f service manual
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Copyright © 2009 LG Electronics. Inc. All right reserved.
Only for training and service purposes
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