The M0-3 Triple Island motor drivers are packaged in a multi-power S030 package. Within this package the sources are bonded out and the drains are underneath the dice coming out through the lead frame. The supply is essentially the lead frame under the two high side drivers and the sources come off here for the motor nodes. These devices start at 17 milliohms per leg with a 30A current limit. For the VNH2SP30 and the VNH3ASP30 there is a current sense pin that acts as an analog feedback. The VNH3SP30 has a digital feedback. The VNH3 devices have a 45 milliohm per leg on resistance and a 30A current limit. Even though they all have a current limit of 30A it is not what these parts can handle in normal operation. These parts will go into thermal shutdown long before 30A. Current capability is limited by the thermal impedance of the system, device and circuit board. That limit is quite a bit lower than the 30A current limit suggests.