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Nokia Customer Care
Troubleshooting Instructions
Company confidential
NPL-4/5/
Issue 2 05/05
Copyright
© 2005
Nokia Corporation. All rights reserved.
Page 59
DC Supply Current Check
For a quick check of DC power supplies refer to the diagram below. Voltage drops are
measured at the respective resistors pads. Note, that not all currents can be checked in
such a way, see the marking <na> (not applicable) in the diagram.
Figure 32: DC Power Supply Diagram
VR1
4.78 V [ 4.6V ... 4.9V ]
charge pump (VCP)
Tx modulator (Vcc_ModOut)
2.81 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)
2.81 V [ 2.70V ... 2.86V ]
RF controls (VPAB_VLNA)
2.81 V [ 2.70V ... 2.86V ]
< na >
V
refRF02
2.81 V [ 2.70V ... 2.86V ]
2.81 V [ 2.70V ... 2.86V ]
2.81 V [ 2.70V ... 2.86V ]
4.1 V [ 2.95V ... 4.7V ]
1.36 V [ 1.32V ... 1.38V ]
< na >
< na >
< na >
< na >
< na >
< na >
< na >
< na >
< na >
< na >
R511( =0R )
0 mV/ <4 mA
R500 ( =5.6R )
90 mV/ 16 mA
R525 =4.7k )
x mV/ y mA
< na >