LG MG810c Service Manual page 31

3. H/W Circuit Description
PWON
END
1
KBR(1)
4
KBR(2)
7
KBR(3)
STAR
KBR(4)
LEFT
KBR(0)
KBC(0)
KBC(1)
KBC(2)
KBC(3)
KBC(4)
KBC(5)
I. Touch Keys
When the folder closed you can control three touch keys , 'PLAY', 'REW', 'FWR' The 'PLAY' key is
connected to the TP100, the 'REW' key is connected to the TP103 and the 'FWR' key is connected to
the TP103. When you touch one of three keys, the 'CY8C21434' senses a variation of capacitance at
the touch pad and the TCH_ACK signal goes to 'LOW' and communicate with DBB by I2C-BUS. Two
touch LEDs are controlled by 'CY8C21434', which uses current sink type.
SIDE_CAMERA
KEYPAD
VA301
EVLC14S02050
2 3 SHUT
5 6 F1
8 9 F2
0 SHAP SEND
RIGHT UP DOWN
Figure 16. Keypad Scanning ckts
1
TP103
P0_1
2
P2_7
3
P2_5
4
P2_3
5
P2_1
TP104 6
P3_3
7
P3_1
8
P1_7
Figure 17. Touch Key ckts
- 30 -
KB301
VA302
EVLC14S02050
CLEAR
OK F3
3V3_TCH 3V3_TCH
TP100 TP101
TP102 C100
LD100
0.1u
LD101
SML-A12UT
SML-A12UT
24
P0_0
23
P2_6
22
U100 P2_4
21
CY8C21434 P2_2
20
P2_0
19 TP105
P3_2
18
P3_0
17
XREX
SIDE_VOLUME
KB302
R304
VA303
100
EVLC14S02050
KB303
R305
VA304
100
EVLC14S02050
R306
100
VA305
EVLC14S02050