neoflash
Advanced Member level 1
This attached diagram shows a sensing scheme that uses 2nd order sigma delta modulator followed by a second order sinc decimation filter.
In this configuration, the out of band quantization noise will be flat instead of rolling off in higher frequency.
In other words, the post filter noise spectrum will be approximately white and quite some noise will alias back.
I think it should be much easier to use 3rd order sinc filter. However, this paper made a different choice made me think that maybe this wide band noise is not a problem when OSR is high enough?
Regards,
Neo
In this configuration, the out of band quantization noise will be flat instead of rolling off in higher frequency.
In other words, the post filter noise spectrum will be approximately white and quite some noise will alias back.
I think it should be much easier to use 3rd order sinc filter. However, this paper made a different choice made me think that maybe this wide band noise is not a problem when OSR is high enough?
Regards,
Neo
