CMX994 Datasheet, PDF (2/61 Pages) CML Microcircuits – Local Oscillator

Direct Conversion Receivers
CMX994/CMX994A/CMX994E
Section
CONTENTS
Page
1
Brief Description...................................................................................................................................... 1
2
History..................................................................................................................................................... 5
3
Block Diagram ......................................................................................................................................... 6
4
Pin and Signal List.................................................................................................................................... 7
4.1
Signal Definitions ............................................................................................................................................8
4.2
Connection of Unused Pins.............................................................................................................................8
5
5.1
5.2
5.2.1
5.2.2
5.3
5.3.1
5.3.2
5.4
External Components .............................................................................................................................. 9
Power Supply and Decoupling ........................................................................................................................9
Receiver ..........................................................................................................................................................10
LNA .................................................................................................................................................................. 10
Mixers and Baseband Section .........................................................................................................................13
Local Oscillator................................................................................................................................................15
Local Oscillator Input ......................................................................................................................................15
VCO and PLL ..............................................................................................................................................15
RESETN ............................................................................................................................................................16
6
6.1
6.1.1
6.2
6.2.1
6.2.2
6.2.3
6.2.4
6.3
6.3.1
6.3.2
General Description................................................................................................................................. 17
General Operation ..........................................................................................................................................18
RX/Tx Enable ..............................................................................................................................................18
Receiver Operation .........................................................................................................................................18
DC Offset Correction.......................................................................................................................................18
Receiver Filters and Bandwidth Options.........................................................................................................19
Baseband Filter Design and Required Correction ...........................................................................................20
Operation at Wider Bandwidths .....................................................................................................................21
Local Oscillator Operation ..............................................................................................................................21
PLL
.............................................................................................................................................. 22
PLL Enable ..............................................................................................................................................23
7
7.1
7.2
7.2.1
7.2.2
7.3
7.3.1
7.3.2
7.4
7.4.1
7.4.2
7.5
7.5.1
7.5.2
7.6
7.6.1
7.6.2
7.7
7.7.1
7.7.2
7.8
C-BUS Interface and Register Descriptions .............................................................................................. 24
General Reset - $10 (no data) .........................................................................................................................25
General Control Register ................................................................................................................................26
General Control - $11 - 8-bit write only..........................................................................................................26
General Control - $E1 - 8-bit read only ...........................................................................................................26
Rx Control Register .........................................................................................................................................27
Rx Control - $12 – 8-bit write only..................................................................................................................27
Rx Control - $E2 – 8-bit read only ...................................................................................................................27
Rx Offset Register ...........................................................................................................................................28
Rx Offset - $13 – 8-bit write only ....................................................................................................................28
Rx Offset - $E3 - 8-bit Read only .....................................................................................................................28
Intermodulation Control Register...................................................................................................................29
IM Control - $14 – 8-bit write only .................................................................................................................29
IM Control - $E4 – 8-bit read only...................................................................................................................29
Rx Gain Register ..............................................................................................................................................31
Rx Gain - $16 – 8-bit write only ......................................................................................................................31
Rx Gain - $E6 – 8-bit read only........................................................................................................................31
PLL M Divider Register ....................................................................................................................................33
PLL M Divider - $22 - $20 – 8-bit write only....................................................................................................33
PLL M Divider - $D2-$D0 - 8-bit read only ......................................................................................................33
PLL R Divider Register .....................................................................................................................................34
 2015 CML Microsystems Plc
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