4. TROUBLE SHOOTING
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4.3 Checking TCXO Block
The output frequency (19.2MHz) of TCXO (X200) is used as the reference one of RTR6285 and PM7540 internal
VCO.
G
G
G
G
G
G
Schematic of the Crystal Part (19.2MHz)
TP3
TP2
TP1
TP2
TP3
TP1
C308
10n
R310
33
100
R303
19.2MHz
KT3225L19200DCW28RA0
X300
4
2
3
1
VCONT
OUT
GND
VCC
C301
0.1u
C320
330p
C307
330p
R319
1
C309
330p
C300
1n
VREG_TCXO_2.85V
VREG_MSMA_2.6V
C310
0.1u
U301
3
2
4
1
5
VCC
GND
R311
100K
TCXO_PM_19.2MHZ
TCXO_EN
TCXO_RTR_19.2MHZ
USBH_SYSCLK
RTR_TRK_LO_ADJ
FFA Rev.C(220Ohm@100MHz)
1.0T
TCXO Circuit
Clesed to TCXO
TP2
TP1
TP3