Xiaofan Chen wrote:
> It is possible to use a MOSFET (NMOS or PMOS) and a good MOSFET driver 
> (Microchip TC4451/4452 are good). But then you do not have those 
> protection built-in.
Yep, I know exactly what you're saying...  And many times, the voltages 
that I was looking for (up to 24V nominal, so you need to handle 30V or 
so peak) aren't supported...   for example, the TC4451/TC4452 only goes 
to 18V.

When I was working through this, it looked like I was talking about 
somewhere around $3.00 for appropriate gate driver IC(s), then another 
$5 for mosfets, and then you still get to play the "how do I protect 
this from thermal runaway and short circuits" game.   When you factor in 
the engineering and cost of the additional parts count (not just the 
parts cost), The LMD18200 sure looked like a good deal to me.

Still would like to cut this down to a $5 for a pair of drivers though...

-forrest
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