A
Andy Iakovlev
- Jan 1, 1970
- 0
Hello:
I am looking for some rules of thumb for RF shielding between the
different stages. In the device I am currently designing there will be:
1) a DDS chip, 100kHz - 175 MHz output;
2) a fully-differential elliptic low pass filter, with 175MHz passband
and 70dB rejection after 225 MHz; applied to the output of 1)
3) a VGA with 50dB control range, applied to the output of 2)
4) a fixed 25dB gain stage, applied to the output of 3)
5) output level detector stage, applied to the output of 4)
6) level-control integrator closing the AGC loop, between 5) and 3),
and I need to choose a minimum number of shielded enclosure cells, to
put the above into.
Thanks in advance for your advice.
-- Andy
I am looking for some rules of thumb for RF shielding between the
different stages. In the device I am currently designing there will be:
1) a DDS chip, 100kHz - 175 MHz output;
2) a fully-differential elliptic low pass filter, with 175MHz passband
and 70dB rejection after 225 MHz; applied to the output of 1)
3) a VGA with 50dB control range, applied to the output of 2)
4) a fixed 25dB gain stage, applied to the output of 3)
5) output level detector stage, applied to the output of 4)
6) level-control integrator closing the AGC loop, between 5) and 3),
and I need to choose a minimum number of shielded enclosure cells, to
put the above into.
Thanks in advance for your advice.
-- Andy