Wcdma Tx Troubleshooting Diagram - Nokia NHM-1 Series Troubleshooting Instructions

CCS Technical Documentation

WCDMA TX Troubleshooting diagram

wcdma TX
troubleshooting
Check maximum output
signal level and linearity:
20...22 dBm @ ch 9750
acp1 < -35 dBc
acp2 < -45 dBc
Pout < 20 dBm
Pout > 22 dBm
Check PA´s voltages
Vpa > 3.4 V ( C970)
Vextreg1 ~2.8V ( C952)
Bias voltage ~1.3V (C980)
Vpa > 3.4 V
Check detector voltage
(C960) ~1.5 V and
phone current 450 ... 500 mA?
Yes
Failed component:
Antenna connector
or duplexfilter
Yes
Failed component:
PA, coupler or
isolator
Issue 1 11/03
ok Check other power levels
and gain control linearity
21...-50 dbm
nok
No TX signal ?
Retune: Temperature
sensor, TX AGC,
Bandresponse calibration
and Detector tuning
Vpa ~ 0 V
Check Vbat > 3.6V (C999)
TXC voltage ~30mV (R971)
PApwr ~1.8V (R996)
Yes
No
No
Check PA input
level ~0dBm
Failed component:
N961 , L999, C995
,open or short circuit
in swithcer
Figure 11: WCDMA TX troubleshooting
Nokia Corporation.
Troubleshooting instructions
Check output power , evm,
ok
linearity, chip timeing error
over several channels and
power levels
Check all TX dc voltages
nok
Yes
nok
perform power sweeps
for TXA1 and TXA 2
No
Check Saw
input power
failed component:
Z900 SAW filter
failed component:
N900 TEX
NHM-1
ok
WcdmaTX
OK!
ok
Check IQ signals
ok
Is synthezier locked to
correct frequency ?
Baseband or SW
troubleshooting
gc control range > 45 dB
gc slope smooth and no
discontinuities, OK?
Refer figure 4
TXA1 not OK
TXA2 not OK
failed component:
N902 HEX
Page 23
nok