The ISO5851 has both, inverting and non-inverting gate control inputs, an active low reset input, and an open drain fault output suitable for wired-OR applications. The recommended application circuit in Figure 10-2 shows a typical gate driver implementation with unipolar output supply and Figure 10-3 shows a typical gate driver implementation with bipolar output supply using the ISO5851.

A 0.1-μF bypass capacitor, recommended at input supply pin V_CC1 and 1-μF bypass capacitor, recommended at output supply pin V_CC2, provide the large transient currents necessary during a switching transition to ensure reliable operation. The 220 pF blanking capacitor disables DESAT detection during the off-to-on transition of the power device. The DESAT diode (D_DST) and its 1-kΩ series resistor are external protection components. The R_G gate resistor limits the gate charge current and indirectly controls the IGBT collector voltage rise and fall times. The open-drain FLT output and RDY output has a passive 10-kΩ pullup resistor. In this application, the IGBT gate driver is disabled when a fault is detected and will not resume switching until the microcontroller applies a reset signal.

Figure 10-2 Unipolar Output Supply

Figure 10-3 Bipolar Output Supply