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There are multiple variants of three-level neutral point clamped inverters. Most are derivatives of two circuit topologies: one with four series-connected FETs and two clamp diodes, the other with two seriesconnected FETs and two clamp FETs. The first one is diode neutral point clamped but simply called neutral point clamped (NPC). The second one is transistor neutral point clamped (TNPC), and the phase leg schematic resembles a sideways letter T. There are different tradeoffs between these two topologies, but in the end the gate drive requirements and implementation are very similar. Of concern is how to safely drive and control the series-connected FETs as well as how to handle fault conditions, including a short circuit. This is explained in this note, in addition to a discussion of overall operation and how it relates to gate driving.