[smartBridges] PowerShot pinout question

[Blaine Fleming]

I have to ask this as I wonder if it might be contributing to some of the 
stability problems.  The powershot uses pins 7 & 8 for positive and pin 5 
for negative.  Pin 4 is used for the device reset button.  PoE typically 
uses two wires for each lead so that the voltage and current drop is 
minimal.  By only using one wire for the negative lead the voltage and 
current drop significantly.  In lab conditions, this won't make a huge 
difference.  However, once temperature is factored in the possible drop on 
100 Feet of cable and a 12 volt supply is likely to be below minimal 
operational limits.  Has all this been considered in the design?

I think that changing the reset button from a normally open type to a 
normally closed type and then adding a transistor and probably a diode to 
the radio would be more effective.  This way the reset wire is always 
acting as a negative lead except when performing a reset.  The additional 
transistor would invert the state of the reset button and provide the 
circuit a connection to the additional negative lead.

It's late at night but I think my thoughts are clear.  Any ideas, thoughts, 
comments?

--Blaine

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