<notthisjoerg...@removethispacbell.net> wrote:
>John Larkin wrote:
>> On 7 Jul 2008 17:04:56 GMT, Scott Seidman
>> <namdiestt...@mindspring.com> wrote:

>>> Joerg <notthisjoerg...@removethispacbell.net> wrote in news:x26ck.31503
>>> $ZE5.27...@nlpi061.nbdc.sbc.com:

>>>>  Noise from clocks and stuff: None.
>>> That's not my experience.  Switched cap filts are famous for clock bleed
>>> through, and you need to be sure your circuit can tolerate this.  The clock
>>> frequency is usually an order of magnitude or more higher than the filter
>>> freq, so you can usually filter out the bleedthrough with an RC.

>> Also famous for aliasing inputs, aliasing power supply noise, and
>> making a heap of noise of their own. But the programmability is nice.

>Look at the bright side: You can make really nice mixers and stuff with
>them. If they just weren't so darn expensive.

>> The world needs a general-purpose programmable continuous-time lowpass
>> filter IC. Really.

>If you use the R2R ladders of DACs you could make one around chips like
>these:
>http://datasheets.maxim-ic.com/en/ds/MAX274-MAX275.pdf

>Of course, then you'd be on the phone with Rebecca all the time.