Key Backlight - LG MG180C Service Manual

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 ).
R307
200
LD300
LEDB
Table 3-10. Keypad Map
KBC1
RIGHT
2
5
8
0
VBAT
R309 R312
R308 R310
200
200 200 200
LD302 LD303 LD304
LD301
Figure 16. Keypad Scanning Scheme
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3. H/W Circuit Description
KBC2
UP
3
6
9
SHAP

KEY BACKLIGHT

R313 R314 R315 R316
200 200 200 200
LD305 LD306 LD307 LD308
R320
10
EVL5M02200
KBC3 KBC4
DOWN OK
CAM CLEAR
F1 VOL_UP
F2 VOL_DOWN
SEND F3
R317
200
LD309
VA305