SLUSDS3A March 2020 – January 2024 UCC21739-Q1
PRODUCTION DATA
To increase the IGBT gate drive current, a non-inverting current buffer (such as the NPN/PNP buffer shown in Figure 8-17) can be used. Inverting types are not compatible with the overcurrent and short circuit fault protection circuitry and must be avoided. The MJD44H11/MJD45H11 pair is appropriate for peak currents up to 15 A, the D44VH10/ D45VH10 pair is up to 20 A peak.
In the case of a over-current detection, the 2-level turn-off is activated. External components must be added to implement safe shutdown instead of normal turn off speed when an external buffer is used. CSTO sets the timing for soft turn off and RSTO limits the inrush current to below the current rating of the internal FET (10A). RSTO should be at least (VDD-VEE)/10. The soft turn off timing is determined by the internal circuitry for 2-level turn-off with soft turn-off current transitions and the capacitor CSTO. CSTO is calculated using Equation 15.