TM8100/TM8200 Service Manual
Frequency Synthesizer Fault Finding
191
© Tait Electronics Limited
June 2006
Task 6 —
3V Power Supply
If the SMPS output and the 6V and 5V supplies are correct, the remaining
power supply to check is the 3V DC supply.
1.
Measure the supply
+3
V
0
AN
at pins 7 and 15 of
IC503
(see
2.
If the voltage is correct, go to
“Phase-locked Loop” on page 192
If it is not, go to
3.
Check the supply at
L506
(see
). The measurement point
is the via shown in the figure.
4.
If the voltage is correct, go to
. If it is not, the 3 V regulator
IC603
is suspect; go to
“Power Supply Fault Finding” on
5.
Check the components in the path from
L506
to
IC503
. Also check
IC503; if necessary, replace IC503 (see
6.
If a fault is found, repair the circuit, confirm the removal of the fault,
and go to
. If the repair failed or no fault
could be found, replace the board and go to
pins 7 and 15 of IC503: 2.9
±
0.3V DC
L506: 2.9
±
0.3V DC
Summary of Contents for TM8235
Page 1: ...TM8100 mobiles TM8200 mobiles Service Manual MMA 00005 04 Issue 4 June 2006...
Page 10: ...10 TM8100 TM8200 Service Manual Tait Electronics Limited June 2006...
Page 62: ...62 Description TM8100 TM8200 Service Manual Tait Electronics Limited June 2006...
Page 148: ...148 Disassembly and Reassembly TM8100 TM8200 Service Manual Tait Electronics Limited June 2006...
Page 162: ...162 Servicing Procedures TM8100 TM8200 Service Manual Tait Electronics Limited June 2006...
Page 178: ...178 Interface Fault Finding TM8100 TM8200 Service Manual Tait Electronics Limited June 2006...
Page 258: ...258 Receiver Fault Finding TM8100 TM8200 Service Manual Tait Electronics Limited June 2006...
Page 446: ...446 Spare Parts TM8100 TM8200 Service Manual Tait Electronics Limited June 2006...