1. Current Capability and Forward Voltage Drop: The DSSK80-0045B offers a higher rated current (40A) and a significantly lower maximum forward voltage (Vf) at the same current level. Under identical operating conditions, the DSSK80 exhibits lower conduction loss, higher efficiency, and can handle greater load current. 2. Reverse Leakage Current and Thermal Stability: The reverse leakage current of the DSSK80-0045B (30 mA @ 45V) is substantially higher—by two orders of magnitude—than that of the STPS6045CW (500 µA @ 45V). This discrepancy is not due to differing test conditions but stems from inherent differences in Schottky barrier design and chip fabrication process. High leakage current can lead to a sharp increase in static power dissipation at elevated temperatures or under high reverse voltage, potentially causing additional temperature rise and imposing stricter requirements on system cooling design. 3. Junction Temperature Range and Reliability Focus: The STPS6045CW has a higher maximum rated junction temperature of 175°C, compared to 150°C for the DSSK80-0045B. This suggests that the ST device offers a wider safety margin in extreme high-temperature environments, possibly due to more heat-resistant process technology or materials. The advantage of the IXYS component lies in its high efficiency (low Vf) under normal operating temperatures. 4. Implied Thermal Performance of Package: The vendor package designation for the DSSK80-0045B is listed as TO-247AD, which is typically an internal manufacturer identifier that may refer to specific pin plating or internal structural optimizations. However, its core package thermal resistance may not differ fundamentally from the standard TO-247-3. Actual thermal performance should be assessed with reference to the specific Rθjc parameter.