4. TROUBLE SHOOTING
(2) Checking DCXO circuits
Checking Points
Pin 28
Checking Flow
Check 26MHz X100. Pin1
Refer to Waveform
Check 26MHz U102. Pin28
Refer to Waveform
Check if there is any
Major Difference
X100
Pin 3
Similar ?
No
Yes
Similar ?
No
Yes
DCXO Circuit is OK
Go to the next stage
- 66 -
U102
Replace X100
Replace U102