The documents below are good references for asphalt driveways and parking lots. Regarding asphalt thicknesses for driveways, the first two documents are specifically about driveways, while the two documents on parking lots can also be referenced by assuming a low level of truck traffic for a driveway.
An interactive pavement design tool at paiky.com
From Ontario Hot Mix Asphalt Producers Association (OHMPA) – ABCs of Driveways
Best Practices for the Use of Asphalt Driveways by the Colorado APA
Seven Steps to a Highly Successful Parking Lot