EVB71120 Melexis Company, EVB71120 Datasheet - Page 7

• Manufacturer Part Number: EVB71120
• Description: Evaluation Board For Mlx71120
• Manufacturer: Melexis Company

2.1
The receiver has two predefined receive frequency plans which can be selected by the RFSEL control pin.
Depending on the logic level of RFSEL pin the sideband selection of the second mixer and the counter
settings for N1 and N2 are changed accordingly. (see in 1.5)
The following table shows the relationships of several internal receiver frequencies for the two input
frequency ranges.
Given IF2 is selectable at either 455kHz or 10.7MHz and the corresponding N
equations can be transferred into the following table.
IF2=455kHz
IF2=10.7MHz
39012 71120 01
Rev. 003
300 to 470
610 to 930
300 to 470
610 to 930
300 to 470
610 to 930
f
f
f
RF
RF
RF
RFSEL
Calculation of Frequency Settings
[MHz]
[MHz]
[MHz]
0
1
f
f
f
f
RF
RF
RF
RF
Injection
f
f
high-low
low-high
−
+
−
RF
RF
+
1.82MHz
0.91MHz
21.4MHz
N
N
42
+
−
f
f
IF1
3
3
IF1
3
3
f
1
1
IF1
8 .
N
N
+
−
MHz
1
1
1
1
f
f
IF2
IF2
f
RFmin
4(f
2(f
2(f
4(f
300
610
RF
RF
N
N
RF
RF
[MHz]
+
+
1
1
+
+
(f
(f
N
N
0.455MHz
0.455MHz
f
f
10.7MHz
10.7MHz
RF
RF
LO1
LO1
Page 7 of 18
f
3
3
3
3
1
1
LO1
−
+
+
+
1
1
f
f
IF2
IF2
f
RFmax
)
)
)
)
)
)
470
930
[MHz]
Evaluation Board Description
f
f
RF
RF
f
f
+
+
RF
RF
N
N
. 0
10.7MHz
f
f
f
300 to 930MHz Receiver
1
1
LO2
LO2
LO2
+
+
455
3
3
−
+
f
f
1
1
IF2
IF2
1
MHz
, N
N
4
2
2
1
EVB71120
counter settings, above
f
f
f
f
RF
RF
RF
RF
N
N
EVB Description
+
+
f
f
+
+
RF
2
RF
2
0.455MHz
0.455MHz
(N
(N
10.7MHz
10.7MHz
f
f
18
f
18
36
36
+
+
RO
RO
RO
1
1
N
12
f
f
6
−
+
IF2
IF2
2
1)
1)
Jan/08