Was wondering if someone could give me a bit of information on my problem. I'm using an arduino mega 2560 and I want to use it with motors with can potentially draw 3 amps.
If possible, I'd like to use an H Bridge chip to control the motors instead of relays. The problem I seem to have is finding a suitable motor driver chip. My question is, would I be able to use the VN770K chip (data sheet attached) to drive 2 of my motors, and interface with an arduino?
The VN770K chip looks interesting but I can't find anyone that stocks it. It also looks as though it would be difficult to heatsink properly. BillHo's suggestion looks good or you might try this one: http://www.national.com/ds/LM/LMD18200.pdf
I have been happy with these -- Pololu - VNH2SP30 Motor Driver Carrier MD01B
The ST VNH2SP30 is good for over 10 amps without a heatsink and has an RDSon of on the order of 20 mOhm.
It is probably a better choice than the VN770K, but it's still a SO-dip package with all the hassles those bring.
Mouser prices them at $12.