From: sleeper75se (sleeper75se_at_yahoo.se)
Date: 2002-01-08 13:24:18
--- In buildcheapeeg_at_yahoogroups.com, "Jim Meissner" <jpmeissner_at_mindspring.com> wrote:
> Dear Andreas:
> The solution was to add resistors between stages of bypass
> capacitors to make R-C filters.
So distributing power for LF-circuits through a bus, is better than a
star formation as long as there is filtering between the stages?
Or is it just another tradeoff?
> > Won't breadboarding cause a lot of trouble in itself, like high
> > parasitic capacitances?
> Just the opposite. PC board will have much higher (but controlled)
> capacitance than point to point wiring.
Ok. Well, I am planning to put a more or less unbroken ground plane
on the top side and run all signals on the bottom. That creates a lot
of capacitance...and it is not exactly a star ground, so it is
perhaps not a good idea? Also, whenever two signals intersect I will
use a piece of wire so that I don't need to break the ground plane.
One might call it a 2.5-layer board.
> You will need some filter ahead of the A/D to get rid of aliases.
I've designed the filter for just that. If the sample rate is 500Hz
or more, there is no theoretical possibility of aliasing up to 100Hz,
with a 10-bit ADC. 1kHz samplerate is sufficient for 16-bit precision.
> You will not find this in the spec sheets. The base emitter is
> not as good as the base collector. The emitter collector makes a
> good low leakage zener diode for op amp bounding.
Thanks, I'll remember this.
/Andreas
This archive was generated by hypermail 2.1.4 : 2002-07-27 12:28:36 BST