A few weeks back, I asked for advice on building an 
H-bridge for an electric go-cart (24V 500W motor).
Heeding the sage advice I received, I have instead built this 
PWM'ed lowside driver using a 16F88 and an IRF540.
   low_side.png
Running on my desk, with no load (drawing ~1A), it runs great!

I'm sure that there are all kinds of problems with it;
I've never done anything like this before and
I would appreciate any suggestions.

I would like to test with a load, but haven't figured out 
a way to do that yet. (The cart is not ready yet.)
Anybody know how to put load on a 500W motor sitting on a desk?

I know that driving the gate at only 5V is not good, 
and I plan to replace the IR540 with a logic level FET.
I did a search on Digikey and found this one:
   DIGIKEY IPP0165N03L G   30V   50A   Rdson=.0065   $1.03
   http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=IPP065N03LGIN-ND
Datasheet:
http://www.infineon.com/dgdl/IPP065N03L_rev1.02.pdf?folderId=db3a30431441fb5d01148c401f250e27&fileId=db3a30431441fb5d011492371ebc0fe2
One US dollar!  It seems almost too good to be true. 
Are there other parameters that I need to check?

For the freewheeling diode, I'm using this one that I found attached 
to a IRFZ34 scrounged from some unknown device a long time ago.
It just says C8255 and I was unable to find a datasheet for it.
I don't know if it is sufficient.
I ordered a MBR2545CT (dual schottky rectifier, 25A 45V).
Is that the right kind of diode for this application?

What else should I do to protect my PIC from this high power stuff?
Especially when I replace the 9V battery with a connection to +24V?

Thank you,
Chris
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