(1) Checking Regulator Circuit
4. TROUBLE SHOOTING
- 78 -
U504
U504. 5 (OUT)
U504. 3(EN)
Regulator Circuit is OK
See next Page to check
VCTCXO
Voltage at
Pin5 of U502
Is 2.85V?
Level at
Pin3 of U502
Is high?
YES
NO
Replace U502
YES
NO
Change main board
C543
4.7u
C544
27p
U504
BYP
4
3
EN
2
GND
IN
1
OUT
5
MIC5255-2.85BM5
C545
27p
2V85_RF
1uF
VBAT
C546
0.01u
C547
CLKON
TEST POINT
CIRCUIT
CHECKING FLOW
Figure 4-3.
Figure 4-4.
Figure 4-5.
Summary of Contents for KG920
Page 3: ... 4 ...
Page 48: ...3 TECHNICAL BRIEF 49 3 8 2 AFE Analog Front End Figure 3 22 ...
Page 52: ...3 TECHNICAL BRIEF 53 3 8 5 MBGM01 5M CCD ISP Figure 3 25 ...
Page 55: ...3 TECHNICAL BRIEF 56 3 8 6 MV8620 5M back end IC Multi Media Function Figure 3 26 ...
Page 58: ...3 TECHNICAL BRIEF 59 3 9 MIDI IC YMU787 Figure 3 27 YMU787 BLOCKDIAGRAM ...
Page 108: ...4 TROUBLE SHOOTING 109 CIRCUIT WAVEFORM Figure 4 59 Graph 4 11 Figure 4 60 Figure ...
Page 109: ...4 TROUBLE SHOOTING 110 TEST POINT U602 FB602 U100 Q100 Q101 C113 C114 Figure 4 61 Figure 4 62 ...
Page 112: ...4 TROUBLE SHOOTING 113 Figure 4 67 Figure 4 68 CIRCUIT ...
Page 115: ...4 TROUBLE SHOOTING 116 WAVEFORM Graph 4 13 ...
Page 139: ...6 BLOCK DIAGRAM 140 6 BLOCK DIAGRAM Figure 6 1 ...
Page 148: ... 149 8 PCB LAYOUT ...
Page 149: ... 150 8 PCB LAYOUT ...
Page 150: ... 151 8 PCB LAYOUT ...
Page 151: ... 152 8 PCB LAYOUT ...
Page 152: ... 153 8 PCB LAYOUT ...
Page 153: ... 154 8 PCB LAYOUT ...
Page 154: ... 155 8 PCB LAYOUT ...
Page 155: ... 156 8 PCB LAYOUT ...
Page 163: ... 164 ...
Page 194: ...Note ...
Page 195: ...Note ...