Alan B. Pearce wrote:
>> So, for now....I'm leaving in the Allegro hall sensor and
>> op-amp and just see if I can function with that or just....
>> leave that piece out.  Its not the most critical part of the design.
>>     
>
> Another option would be to use a second stage of gain purely for detecting 
> very small currents, and when that stage saturates (or the output is larger 
> than some value below saturation) then look at the output of the earlier 
> stage (I assume this is some form of metering application).
>
> As you are using Allegro devices, how sensitive are they to nearby magnetic 
> fields? I haven't gone digging in the datasheets and app notes for detailed 
> info as yet, as this project is still in the incubation stage. 
>
>   
I am using the +/- 50A version current sensor from Allegro. I am very 
impressed. I have NOT noticed
any effects from nearby PCB traces or cables placed near it.

I am using it to monitor motor current, and because of the DC motor 
driver's pulse controller, I have to
use a RC network to clean up the output, but it really works well. 
Priced at about $6 USD.

I only wish there were a smaller version of this, say +/- 5A instead of 
50A. Oh well.

--Bob
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