Nokia Customer Care
Appendix A: RF Troubleshooting
A-80
Company Confidential
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2005 Nokia. All rights reserved
4.1.1.3.2 Does WCDMA PA (N7503) get operating voltage Vcc11?
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WCDMA transmitter has to be active before measurements. Procedure is explained in section
“Transmitter troubleshooting”.
•
Set TX power level to -40 dBm (Set start level to “-40.0” in Phoenix)
•
Measurements can be done with an oscilloscope and a probe.
•
Connect the probe to C7580.
•
Vcc11 voltage level should be about 1.5 V. The same voltage level should be measured also with all
power levels smaller than about 10 dBm. Vcc11 is about 3.3 V with the highest power (21 dBm).
NOTE: Perform WCDMA transmitter tests with > 0 dBm power only in RF shielded environment.
4.1.1.3.2.1 L7515, C7589 and C7580 in place and working correctly?
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Check that components are in place and solder joints are ok
•
Disconnect the power supply from the phone and use an ohmmeter to check that L7515 is
conducting DC.
•
Use an ohmmeter also to check that capacitors are not short-circuited. If short-circuit is found
replace capacitors mentioned above.
4.1.1.3.2.2 Does SMPS N7504 get operating voltage Vdd (=VBAT_PA)?
•
WCDMA transmitter has to be active before measurements. Procedure is explained in section
“Transmitter troubleshooting”.
•
Measurement can be done with an oscilloscope and a probe.
•
Connect the probe to C7569 (or C7564, C7583)
•
VBAT_PA voltage level should be 3.05 – 5.4 V. Typical value is 4.0 V.
4.1.1.3.2.3 Is there correct DET_SW_W –voltage coming from Vinku ASIC (N7501)?
•
WCDMA transmitter has to be active before measurements. Procedure is explained in section
“Transmitter troubleshooting”.
•
Measurement can be done with an oscilloscope and a probe.
•
Connect the probe to C7586.
•
Voltage level should be about 2.78 V.
4.1.1.3.2.3.1 Replace Vinku (N7501)
4.1.1.3.2.4 Does SMPS get correct control voltage from the WCDMA power detector (signal Vcontrol)?
•
WCDMA transmitter has to be active before measurements. Procedure is explained in section
“Transmitter troubleshooting”.
