3. TECHNICAL BRIEF
- 30 -
3.8 Keypad Switches and Scanning
The key switches are metal domes, which make contact between two concentric pads on the keypad
layer of the PCB when pressed. There are 26 switches (Normal Key 24EA, Volume up down side key),
connected in a matrix of 5 rows by 5 columns and additional GPIO 35 for KEY_ROW5, as shown in
Figure 3-11, except for the power switch (KB1), which is connected independently. Functions, the row
and column lines of the keypad are connected to ports of AD6720. The columns are outputs, while the
rows are inputs and have pull-up resistors built in. When a key is pressed, the corresponding row and
column are connected together, causing the row input to go low and generate an interrupt. The
columns/rows are then scanned by AD6720 to identify the pressed key.
3
9
UP
VOL_DOWN
CONF
LEFT
SEND
MENU
1
*
4
5
SEL
END
RIGHT
CLR
0
T
FAV
VOL_UP
6
2
DOWN
8
7
#
VA307
EVL14K02200
VA303
EVL14K02200
EVL14K02200
VA313
680
R320
EVL14K02200
VA306
SW312
680
R342
SW326
VBAT
SW317
SW319
R303
100
SW304
SW318
SW315
EVL14K02200
VA304
680
R339
SW305
R343
680
680
R336
R326
680
680
R301
SW300
EVL14K02200
VA302
SW324
EVL14K02200
VA305
SW322
SW311
CN601
1
2
3
4
R324
680
R302
100
SW316
SW314
VA312
EVL14K02200
SW308
VA301
EVL14K02200
10K
R300
SW323
SW325
SW307
SW310
SW320
680
R331
SW313
680
R344
SW309
R341
680
SW321
SW306
KEY_ROW2
KEY_COL1
KEY_COL0
KEY_COL4
KEY_ROW1
KEY_COL3
KEY_ROW3
KEY_ROW4
KEY_COL2
KEY_ROW0
POWERKEY
Figure 3-11. Keypad Switches and Scanning
Содержание KG225
Страница 1: ...Date April 2006 Issue 1 0 Service Manual Model KG225 Service Manual KG225 M O B ILE CAM E R A ...
Страница 3: ... 4 ...
Страница 19: ...3 TECHNICAL BRIEF 20 Figure 3 4 SYSTEM INTERCONECTION OF AD6720 EXTERNAL INTERFACE ...
Страница 66: ...4 TROUBLE SHOOTING 67 4 12 KEY backlight Trouble Q300 R359 TEST POINT Figure 21 ...
Страница 79: ... 80 5 DOWNLOAD B Multi Download Procedure 1 Run GSM Multi Download program and select Setting ...
Страница 82: ... 83 5 DOWNLOAD 7 Check if the ADI option is set to Hermes 8 Press OK to end Configuration Select Rate ...
Страница 84: ... 85 6 BLOCK DIAGRAM 6 BLOCK DIAGRAM ...
Страница 85: ... 86 ...
Страница 92: ... 93 KG225 8 PCB LAYOUT ...
Страница 93: ... 94 KG225 8 PCB LAYOUT ...
Страница 101: ... 102 10 STAND ALONE TEST Figure 10 2 HW test setting Figure 10 3 Ramping profile ...
Страница 109: ... 110 ...
Страница 125: ...Note ...
Страница 126: ...Note ...