New lower price for Axon II ($78) and Axon Mote ($58).
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Hi,Switching times are determined by how much charge you move how fast, just plucking some ideal or maximum values from a datasheet won't ensure a proper deadband.It may be easier for you to feedback the actual conditions to the CPLD and then disallowing a short alltogether - this way you would get the minimum deadband needed at all times.Switching MOSFETs off (as well as on) is faster when you move the charge faster - think at least 3A..5A short term to get a decent shift. IOW, use drivers between the CPLD and the gates of the transistors.
You talk about amp, 3a to 5a, but from what I've read the mosfet's gate does not see current, it sees voltage, the impedance of the gate is so high that current isnt a factor. Thus, as we often see a floating gate on a mosfet will often keep it's last known state....due mostly to it's inherent capacitance of 1000pf or thereabouts.
Will probably be an eBook on one of my own sites though, but that shouldn't detract from the assumed usefullness
I breadboarded the design here, except I used the IRF9530 and IRF530 mosfets instead.http://www.cadvision.com/blanchas/hexfet/np-s.htmThis doesnt work because the lower N channel MOSFETs are not turning off completely causing one of the N channels to get very hot.