PNP transistors in cascode configuration on the high side to increase voltage capability.
NPN transistors in cascode configuration on the low side for same reason.
Note the blue/green and the red/orange pairs of traces are never more then half of the high supply voltage away from each other.
This example shows switching 750V with transistor that might, for example breakdown at 450V.
The input voltage can be as low as 1V, or whatever the saturation base/emitter voltage is for the use NPN transistor.
