TH71221_15 Datasheet, PDF (39/44 Pages) Melexis Microelectronic Systems – FSK/FM/ASK Transceiver

9 TX/RX Combining Network
9.1 Board Component List (Fig. 19)
Part
CRX0
CTX0
CTX1
CTX2
CTX4
LRX2
LTX0
LTX1
CB2
Size
0603
0603
0603
0603
0603
0603
0603
0603
0603
Value @
315
MHz
100 pF
10 pF
10 pF
10 pF
12 pF
82 nH
15 nH
33 nH
330 pF
Value @ Value @ Value @
433.92 868.3
915
MHz
MHz
MHz
100 pF
10 pF
6.8 pF
6.8 pF
4.7 pF
56 nH
15 nH
33 nH
330 pF
100 pF
10 pF
5.6 pF
3.9 pF
2.2 pF
15 nH
3.9 pF
10 nH
330 pF
100 pF
10 pF
4.7 pF
3.9 pF
1.8 pF
15 nH
3.9 nH
10 nH
330 pF
TH71221
27 to 930MHz
FSK/FM/ASK Transceiver
 No TX/RX switch required
 Direct connection to /4 antenna possible
CB2
VCC
RF input
RF output
LTX1
50
CTX2 CTX1
LTX0
CTX4
CTX0
LRX2
CRX0
25 OUT_PA
26 IN_LNA
Fig. 19: Combining network schematic
9.2 Typical LNA S-Parameters in Receive Mode
Low Gain Mode
Frequency
27 MHZ
40 MHz
80 MHz
170 MHz
315 MHz
433 MHz
868 MHz
915 MHz
Re[S₁₁]
0.9138
0.9139
0.9126
0.9054
0.8836
0.8622
0.7161
0.6975
Im[S₁₁]
-0.0145
-0.0229
-0.0481
-0.1026
-0.1814
-0.2625
-0.4577
-0.4753
Re[S₁₂]
6.06E-005
5.53E-005
5.36E-005
7.44E-004
2.16E-004
7.81E-004
2.35E-003
2.24E-003
Im[S₁₂]
4.27E-004
6.73E-004
1.48E-004
3.25E-003
6.21-E003
6.34E-003
1.09E-003
1.10E-003
Re[S₂₁]
-0.4172
-0.4092
-0.3989
-0.3828
-0.3300
-0.3248
-0.1265
-0.1062
Im[S₂₁]
0.0334
0.0400
0.0581
0.1056
0.1798
0.2168
0.3187
0.3206
Re[S₂₂]
0.9986
0.9984
0.9979
0.9966
0.9926
0.9870
0.9543
0.9494
Note: input and output of the LNA are connected to 50  ports without matching elements
Im[S₂₂]
-0.0095
-0.0136
-0.0265
-0.0558
-0.1033
-0.1417
-0.2829
-0.2980
High Gain Mode
Frequency
27 MHZ
40 MHz
80 MHz
170 MHz
315 MHz
433 MHz
868 MHz
915 MHz
Re[S₁₁]
0.8417
0.8424
0.8403
0.8273
0.7884
0.7492
0.5007
0.4714
Im[S₁₁]
-0.0151
-0.0276
-0.0621
-0.1344
-0.2328
-0.3405
-0.5322
-0.5440
Re[S₁₂]
1.36E-004
1.42E-004
1.52E-004
1.86E-004
4.02E-004
1.51E-004
2.36E-004
1.94E-004
Im[S₁₂]
8.63E-005
1.07E-004
1.83E-004
3.72E-003
7.04E-003
6.18E-003
1.06E-003
1.06E-003
Re[S₂₁]
-4.0840
-4.0840
-4.0630
-3.9550
-3.5100
-3.4700
-1.6710
-1.4690
Im[S₂₁]
0.1272
0.2055
0.4338
0.9279
1.6990
1.9920
3.2230
3.2700
Re[S₂₂]
0.9994
0.9994
0.9991
0.9977
0.9846
0.9839
0.9501
0.9451
Note: input and output of the LNA are connected to 50  ports without matching elements
Im[S₂₂]
-0.0092
-0.0135
-0.0269
-0.0571
-0.1072
-0.1439
-0.2847
-0.2995
39010 071221
Rev. 009
Page 39 of 44
Data Sheet
Nov/15