MGCM02
TDMA/AMPS IF and Baseband Interface
Data Sheet
Features
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Complete IF to Baseband for IS136
100dB Gain Control
Channel Filtering (30kHz)
FM Demodulator
RSSI Output
Dual IF Synthesisers
Fully Programmable via serial bus
3 Volt operation
49 Ball BGA package (7 x 7 mm)
Ordering Information
MGCM02/KG/BP1N
MGCM02/KG/BP1Q
April 2003
Applications
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Dual Mode TDMA/AMPS Mobile telephones
Dual Band (PCS1900/900) TDMA/AMPS Mobile
telephones
PCS 1900 TDMA Mobile Telephones
Description
The MGCM02 provides the complete IF to baseband
I and Q including channel filtering for IS136/AMPS.
The receive input is at an IF frequency up to
200MHz. This is downconverted to an internal IF of
60kHz and filtered by a switched capacitor bandpass
filter which also provides image rejection. The 60kHz
signal is then demodulated to give baseband I and Q
signals. Over 100dB of gain control is provided. The
baseband outputs can be input directly to an A to D
converter.
The internal FM discriminator can be used for
demodulating AMPS signals. The receive path also
provides RSSI.
Transmit I and Q baseband signals from D to A
converters can be input directly to MGCM02 which
provides reconstruction filters and a variable gain
buffer.
The two PLL synthesisers are used for generation of
the receive and transmit IF LO signals.
Receive Section
RXI OP+,-
60kHz
IF IP+,-
Σ
90Î
60kHz
RXQ OP+,-
LO +
LO -
To Rx PLL
RSSI
AUDIO FB
FM
Discrim
AUDIO
RSSI FB
RSSI
Transmit Section
Tx FM
SCLK
TX
IIP+,-
TXQ
IP+,-
TXI
OP+,-
TXQ
OP+,-
SDATA
SLATCH
RESETB
PCA
Control
Rx
VCO
Synthesisers
Rx
Rx PD
Rx LOCK
Tx
VCO
Tx
Tx LOCK
Tx PD
Figure 1 - Block Diagram
1