IGBT Forum Discussions

+(red) to gate 2 and   -(black) to gate 8 reads: 315 (mV?)

- (black) to gate 2 and  +(red) to gate 8 reads: OL (Open loop)

+(red) to gate 5 and   -(black) to gate 8 reads: OL (Open loop)

-(black) to gate 5 and  +(red) to gate 8 reads: 315 (mV?)

In addition, I have verified that the gate driver is working since it reads ~ -8 V when not commanded, and +15 V when commanded on via a logic signal. To briefly summarize the circuit setup, a + terminal of a capacitor connects to the collector (pin 9 of the IGBT) continuing via the emitter (pin eight) to an electrode. The - terminal of the capacitor is connected to an other electrode. The issue is that the voltage across the electrodes is always high, somehow implying that the IGBT itself is either on or leaking even when there is no logic signal to open the gate. It is worth noting that even outside of this circuit, the IGBT seems to be perpetually on when tested with a 15 V DC power supply. This issue is unlikely to be either the IGBT or the gate driver alone since both components have been replaced but the issue persists. 

Any advice moving forward would be appreciated.