User Guide

Issue 1 04/2005 COMPANY CONFIDENTIAL 39
Copyright © 2005 Nokia. All Rights Reserved.
RM-94
6(b) - RF Troubleshooting Nokia Customer Care
DC Supply Voltage Check
For a quick check of DC power supplies, refer to the diagram below. The RF power supplies
are generated in the UEM and can be measured either in the Small Signal Chamber or in the
Base Band Chamber.
The UEM output voltages can be measured at the respective resistors' / capacitors' pads
marked below in brackets, e.g. < C1234 >.
VR1
4.75 V [ 4.6V ... 4.9V ]
charge pump (VCP)
Tx modulator (Vcc_ModOut)
2.78 V [ 2.70V ... 2.86V ]
VCTCXO (+VCC)
digital interface (VDIG)
VR4
VR3
VR2
PLL prescaler (VPRE)
VR5
phasing dividers of Rx (VLO)
BB buffer (VDIG)
VR6
Rx Front End (VRF_RX)
16 mA [max. 20 mA]
VCO (VCC_VCO)
VR7
UEM
Triple band PA
VBAT
100 uA
bias reference (VB_EXT)
V
refRF01
TX buffer & EDGE ALCs (VRF_TX)
Bias & Rx CH filters (VF_RX)
2.78 V [ 2.70V ... 2.86V ]
RF controls (VPAB_VLNA)
2.78 V [ 2.70V ... 2.86V ]
100 uA
bias reference
(RXIINN, RXQINN)
V
refRF02
2.78 V [ 2.70V ... 2.86V ]
2.78 V [ 2.70V ... 2.86V ]
2.78 V [ 2.70V ... 2.86V ]
2.7 V [ 2.95V ... 4.7V ]
1.35 V [ 1.32V ... 1.38V ]
1.35 V [ 1.32V ... 1.38V ]
< C7516 >
< R7516 >
< C7519 >
< C7517 >
< C7521 >
< C7500 >
< R7511/C7516 >
< R2901/C2901 >
AND
< R2900/C2900 >
< C7510 >