Hi Bob, there are “special” blades that will minimize splintering just goto the local hardware store and look around (or ask). Basically speaking the more teeth the better for less splintering. One other thing that will help is to cover both sides of the cutline with some “Blue” masking tape this will assist in keeping the wood from splintering/chipping.
You may want to read a Tip/Tricks article at my site Circular Saw Cutting for more info as well.
Hope this helps,
Wick!