Board description
AN2451
22/55
Doc ID 12791 Rev 3
Figure 12.
Measured frequency response of the Tx passive filters
connected to the CISPR network (typical curve)
Figure 13.
Simulated frequency response of the Tx passive filters
connected to the CISPR network with the components tolerance effect
5.1.3
Rx passive filter
The Rx filter is made up of a resistor in series with a parallel L-C resonant. The transfer
function of the filter can be written as:
Equation 4
where R
L
is the DC series resistance of the inductor (in our case, about 2
Ω
). The center
frequency and the quality factor of the filter can be expressed as:
+/
‐
1
dB
R s
( )
s
L
6
R
L
+
•
R
17
L
6
C
26
----------------------------
s
2
R
17
R
L
C
26
L
6
+
R
17
L
6
C
26
---------------------------------------
s
R
17
R
L
+
R
17
L
6
C
26
--------------------------
+
•
+
----------------------------------------------------------------------------------------------
=
Содержание ST7540
Страница 47: ...AN2451 Application ideas Doc ID 12791 Rev 3 47 55 Figure 47 Line coupling interface for 110 kHz channel...
Страница 48: ...Application ideas AN2451 48 55 Doc ID 12791 Rev 3 Figure 48 Line coupling interface for 132 5 kHz channel...
Страница 51: ...AN2451 Board layout Doc ID 12791 Rev 3 51 55 Appendix A Board layout Figure 49 PCB layout component placing...
Страница 52: ...Board layout AN2451 52 55 Doc ID 12791 Rev 3 Figure 50 PCB layout top view...
Страница 53: ...AN2451 Board layout Doc ID 12791 Rev 3 53 55 Figure 51 PCB layout bottom view...
