Service Manual
Trium 110
Version A
Date: 05/02
18/22
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:
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FAX
:
Mitsubishi Electric Telecom Europe S.A.
After Sales Services
Z.A. Pigeon Blanc, 35 370 St Germain du Pinel France
+33 (0)2 23 55 16 30
+33 (0)2 99 75 71 62
10.2
Synthetiser Circuit Description.
Switching between GSM and DCS band is performed by programming the IC401 with the serial data in BBE from CPU.
The serial data lines are connected directly to the serial input pin of the RF IC (IC 401), and are used to program the 2 PLLs of
the IC.
The RF IC has two PLLs : one is variable frequency (RF PLL), and the other is fixed frequency (IF PLL).
RF-PLL : variable frequency PLL for RX and TX for both GSM and DCS bands.
Oscillation Frequency Ranges :
- For E-GSM Band / 1150 - 1185MHz
-
For DCS TX / 1575 - 1650MHz
-
For DCS RX / 1580 - 1655MHz
IF-PLL : Fixed frequency 424 MHz for IF of TX for both E-GSM and DCS bands.
Fixed frequency 360 MHz for IF of RX for both E-GSM and DCS bands.
The signal BANDSW controls the E-GSM/DCS Band switching.
BANDSW
RF BAND
0
E-GSM
1
DCS
In order to achieve the channel spacing, the reference frequency is set to 200 kHz.
IF
PLL
RF
PLL
IC401
RF
VCO
OSW
CLK
SDATA
EN
RF DUAL
BAND
TCXO
13Mhz
IC600
X600
