The Path Of Mjoelner Rf Asic; The Path Of The Pa; Antenna Switch - Nokia RH-29 Series Manual

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RX
Dir. Coupler
GSM
TX
RX
DCS
PCS
TX

The path of Mjoelner RF ASIC

The balanced TX signal from base band is coming to Mjoelner RF ASIC. The GSM1800
path includes a RF modulator for GSM1800. The BB signal is up-converted with the LO
signal corresponding to the wanted TX channel. The GSM1800 TX output of Mjoelner is a
balanced signal.
From the output of Mjoelner the signal is fed through the Balun T701 (Balanced to single
ended) and a 3 dB pad.

The path of the PA

The GSM1800 part of the PA has a maximum output of approximately 33dBm. The sup-
ply is coming directly from the Battery connectors.
The output is controlled by the power control loop. From the output of the PA the signal
goes through the directional coupler (one of the power control loop components) to the

Antenna Switch.

Issue 1 05/2004
Company Confidential
Balun
PA
Buffer
PCS
DCS1800
VTX
SAW
Buffer
EGSM900
GSM850
PW-
DET loop
filter
VBATTRF
Copyright © 2004 Nokia Corporation
Company Confidential
6b - RF Troubleshooting
VANTL /
VANTH
RF
VDDDIG
Controls
VB_DET
VDDRXBB
VTXLOL
RF
Controls
VTXBH
VTXBL
OUTHP
OUTHM
Open collector
Open collector
OUTLP
OUTLM
DET
PLFB1
PWC
PLFB2
VPCH/VPCL
2
TXP TXC
RH-29
MJOELNER
1/2 1/4
2
2 2 2
2 2
Supply
filter
VR2
Page 3