Slkor MOSFETs

Low-voltage MOSFETs (20V-100V) are optimized for battery-powered and low-voltage DC applications with extremely low RDS(on) to minimize conduction losses. They typically have lower gate charge for faster switching. High-voltage MOSFETs (500V-900V) are designed for AC-DC power supplies and must withstand high voltage stress. They have higher RDS(on) but are optimized for switching losses and EMI performance. The choice depends on your application's voltage level and whether the priority is conduction loss (low-voltage) or blocking voltage capability (high-voltage).

For battery applications (3.3V-48V), use low-voltage MOSFETs. For AC-DC supplies from mains voltage, use 600V-900V high-voltage MOSFETs. Contact our FAE team for specific recommendations.

Conduction loss in a MOSFET is calculated using P = I² × RDS(on) × D, where I is the RMS current through the device, RDS(on) is the on-resistance at operating temperature, and D is the duty cycle. Note that RDS(on) increases with temperature - typically 1.5x to 2x higher at 100°C than at 25°C. For accurate calculations, use the maximum RDS(on) from the datasheet at your expected operating temperature. Also consider that RDS(on) increases with gate voltage - ensure your drive voltage provides the specified RDS(on).

Use our online MOSFET loss calculator or contact our FAE team for detailed thermal and loss analysis for your specific application conditions.

Gate charge (Qg) determines the switching speed and drive power requirements of a MOSFET. Lower Qg enables faster switching (reducing switching losses) and requires less drive current from the gate driver. Total gate charge consists of Qgs (gate-source) and Qgd (gate-drain, also called Miller charge). The Miller charge is particularly important as it determines the voltage fall time during switching. For high-frequency applications (>100kHz), select MOSFETs with low Qg and Qgd to minimize switching losses and EMI.

For high-frequency switching applications, prioritize low Qg MOSFETs. Our FAE team can recommend optimal devices based on your switching frequency and driver capability.

Temperature significantly affects MOSFET performance in several ways: RDS(on) increases approximately 0.4% per °C, meaning a device with 10mΩ at 25°C may have 15-20mΩ at 100°C

Maximum current rating decreases at higher temperatures due to increased RDS(on) and reduced thermal margin

Gate threshold voltage decreases with temperature, potentially affecting turn-off behavior

and Leakage current increases exponentially with temperature. Always design for worst-case operating temperatures and use the RDS(on) values specified at elevated temperatures in the datasheet.

Design thermal management for maximum ambient temperature plus self-heating. Our FAE team can provide thermal modeling and heatsink selection guidance.

Avalanche rating indicates a MOSFET's ability to withstand voltage transients that exceed its breakdown voltage. When the drain voltage exceeds V(BR)DSS, the MOSFET enters avalanche breakdown, conducting current while dissipating energy. The avalanche energy rating (EAS) specifies how much energy the device can safely absorb in a single pulse. This is important for inductive load switching where voltage spikes occur. Slkor MOSFETs are avalanche rated, providing robustness against unexpected voltage transients without external protection.

For inductive loads (motors, solenoids, relays), select avalanche-rated MOSFETs or add external protection. Contact our FAE team for inductive switching application guidance.