Hardware Peripheral System Of Stn8810 - LG KT610 Service Manual

3. TECHNICAL BRIEF

3.10 Hardware Peripheral system of Stn8810

3.10.1 Keypad
KS10 has 75 buttons, 19 keys in Folder, 54 keys in main and 2 side keys.
KT610 use key coder IC because Stn8810 has not enough GPIO.
Key coder IC use interrupt and I2C interface for communication with STn8810.
Figure shows the Keypad circuit.
'END' Key is connected to PM_ON_SW_N to PM6658
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LGE Internal Use Only
K E Y C O D E R
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Figure. Schematic of key coder IC
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Copyright © 2008 LG Electronics. Inc. All right reserved.
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Only for training and service purposes
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