Neueste Meldungen von Diotec

Discover our bootstrap diode BYG23T in SMA package, well suited for high-side floating gate driver circuits. The major challenge here is to select a robust device with respect to high voltage peaks during low side MOSFET or IGBT turn-off, as well as forward surge currents during re-charging of the storage capacitor. High frequency operation is state-of-the-art in these applications.

The BYG23T features an avalanche rating of 5mJ with breakdown voltage of 1350V and a very low reverse recovery time of 75ns. Repetitive peak forward current rating is 3A, and average forward current 1A.

Various half-bridge gate driver circuits are currently available in the market with integrated bootstrap diodes. The total power dissipation of such gate driver IC is the combination of gate driver losses and the internal bootstrap diode losses. The difficulty with this circuit is the operation at higher frequencies and load capacitance applications, where the power losses in the internal bootstrap diode dominates the overall power dissipation.

An external bootstrap diode, even if in parallel with the internal one, can significantly overcome the problem of excessive power losses in the driver IC. A stand-alone operation is of course possible as well.