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Only for training and service purposes
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4. TROUBLE SHOOTING
(4) Checking TX I/Q
Graph 4.3.4
Re-download the Software
And calibrate
Check if there is
Any Major Difference
¨
Refer to Graph4.3.4
Similar?
Yes
No
Replace U501
CHECKING FLOW
WAVEFORM
Figure 4.2.3
TEST POINT
CIRCUIT
Figure 4.2.3
TP7
TP8
TP7
TP8
C522
39p
12
13
VDD
15
VLDO1
VLDO2
16
9
VLDO3
RX1900B
RX850
32
31
RX850B
RX900
30
29
RX900B
SCLK
6
5
SD
A
T
A
7
SEN
11
TXOP_HI
TXOP_LO
10
18
V
A
FC_NC
VBAT
14
VCC_BBI
4
24
VCC_BBQ
1
VCC_FE
VCC_REF
17
VCC_TXVCO
EUSY0280101
AD6548
U501
GND
33
I
2
3
IB
NC
8
Q
23
22
QB
20
REFIN
REFINB
19
REF_OP
21
RX1800
28
27
RX1800B
RX1900
26
25
0.1u
C509
27p
C521
2V75_VVCXO
C505
DNI
C526
DNI
IN
QN
QP
IP
T
P7
T
P8