Key Baclklight Led Interface - LG GM210 Service Manual

3.15 KEY BACLKLIGHT LED Interface

The AD6725 Auxiliary Section provides three independent PWM light controllers.
The PWM output controllers regulate the average current through active lights.
The output frequencies of the LIGHTx PWM output controllers are set by the Light12Period (0x2F ) and
Light3Period (0x31 ) control registers.
With fMCLK = 13 MHz, frequencies ranging from 50.781 kHz to 49.591 Hz may be specified.
fLIGHT1 = ( fMCLK / 256 ) / ( Light12Period[9:0] + 1 )
fLIGHT2 = ( fMCLK / 256 ) / ( Light12Period[9:0] + 1 )
fLIGHT3 = ( fMCLK / 256 ) / ( Light3Period[9:0] + 1 )
he output duty cycles of the PWM output controllers are set by the LightxDutyCycle[7:0] control registers –
Light1DutyCycle (0x2D ), Light2DutyCycle (0x2E) and Light3DutyCycle (0x30 ).
This model use only Light3 port and 2 high luminance white LED with light guard film.
LGE Internal Use Only
Copyright © 2009 LG Electronics. Inc. All right reserved.
Only for training and service purposes
Figure 3-15-1 ABB Light Controller Block Diagram
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3. TECHNICAL BRIEF
Copyright © 2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only