LG CG225 Service Manual page 37

3. H/W Circuit Description
3.5.12. Keypad Switching & Scanning
KBC0
KBR0 LEFT
KBR1 1
KBR2 4
KBR3 7
KBR4 STAR
DBB supports 25 Key Map and Switch-ON Key is connected directly to ABB as (Figure16 ).
KEY
KBR(1)
C314
1000p
KBR(2)
C317
1000p
KBR(3)
C318
1000p
KBR(4)
C319
1000p
KBR(0)
C320
1000p
KBC(0)
KBC(1)
KBC(2)
KBC(3)
KBC(4)
Table 3-10. Keypad Map
KBC1
RIGHT
2
5
8
0
SW301
VA301
1
1 2 1 2 1 2
KB301
KB302 KB303
1 2 1 2 1 2 1
KB304 KB305 KB306
1 1 1
1 2 2 2
KB307 KB308 KB309
1 1 1
2 2 1 2
STAR KB310
SHARP
1 1 1 1
2 2 2
LEFT RIGHT UP
C321
1000p
C322
1000p
C323
1000p
Figure 16. Keypad Scanning Scheme
KBC2
UP
3
6
9
SHAP
CAM SIDE KEY
VA302
PWON
2 2
1
CLEAR
CAM
2
F301
VOL_UP
VOL_DOWN
COMMON
2
F302
2 1 2
F303
SEND
VA305 VA306
VA307
1 2
2
DOWN OK
C324
1000p
C325
1000p
- 36 -
KBC3 KBC4
DOWN OK
CAM CLEAR
F1 VOL_UP
F2 VOL_DOWN
SEND F3
END
R323
1 2
620
VA303
CN303
4
3
2
1