1. Forward Voltage Drop (Vf): The Vf of the MBRF20100CTG (850mV @10A) is significantly higher than that of the MBRF20H100CT-E3/45 (770mV @10A). At identical operating currents, the MBRF20100CTG exhibits higher conduction losses and greater heat generation. In efficiency-sensitive or thermally constrained applications, this may lead to increased temperature rise, necessitating a re-evaluation of the thermal design. 2. Reverse Leakage Current (Ir): The reverse leakage current of the MBRF20100CTG (150µA @100V) is over an order of magnitude greater than that of the MBRF20H100CT-E3/45 (4.5µA @100V). Under high-temperature and high-reverse-voltage operating conditions, the static power dissipation of the MBRF20100CTG increases significantly. This can impact system efficiency and imposes higher reliability requirements in high-temperature environments. This parameter difference directly reflects the disparity in Schottky barrier manufacturing processes and the quality of the chip material between the two devices. 3. Thermal Mounting Structure: The MBRF20H100CT-E3/45 is explicitly marked as having an "Isolated Tab," meaning the metal tab of its ITO-220AB package is electrically isolated from the internal pins. The MBRF20100CTG (TO-220FP) does not specify this feature; its tab is typically connected to the center pin (cathode). If the original design leverages the isolated tab feature to directly connect the heatsink to the chassis or ground for optimal cooling, replacing it with the MBRF20100CTG requires the addition of an insulating washer to prevent a short circuit. This introduces additional thermal resistance, potentially compromising thermal performance. 4. Product Series Positioning: The MBRF20100CTG belongs to onsemi's "SWITCHMODE™" series, optimized for switching power supplies. The Vishay part does not indicate a special series designation. This difference relates to vendor marketing positioning and does not directly determine performance, but it may imply a different design focus.