Multi-phase cascaded bridge for dc/dc, ac/dc, and dc/ac applications

A motor drive comprising an inverting bridge and control circuitry, wherein the inverting bridge has an input that receives an input voltage and an output that delivers a multi-phase voltage to a plurality of motor windings;

• wherein:
• the inverting bridge comprises a plurality of half bridges cascaded across the input voltage, each half bridge comprising:
• an input capacitor;
• upper and lower switches coupled across the input capacitor and connected at a switch node;
• and
• a DC blocking capacitor coupled between the switch node and a primary winding terminal of the transformer;
• and
• the control circuitry monitors one or more inverter feedback signals and generates in response thereto inverter drive signals that operate the upper and lower switches of the plurality of half bridges in a phase staggered manner.

An isolated switching converter comprising an inverting bridge, one or more transformers, a rectifying bridge, and control circuitry, wherein:

• the inverting bridge has an input that receives an input voltage and an output including a plurality of bridge attachment points and a plurality of switch nodes that can be selectively connected to a plurality of transformer primary windings, the inverting bridge further having a plurality of half bridges cascaded across the input voltage, each half bridge comprising:
• an input capacitor coupled between two of the plurality of bridge attachment points corresponding to the half bridge;
• upper and lower switches coupled across the input capacitor and connected at a switch node of the plurality of switch nodes corresponding to the half bridge;
• and
• a DC blocking capacitor coupled between the switch node corresponding to the half bridge and a primary winding terminal of the one or more transformers;
• and
• the rectifying bridge has an input coupled to one or more secondary windings of the one or more transformers and an output that delivers an output voltage to an output of the isolated switching converter, the rectifying bridge comprising one or more rectifier switches;
• and
• the control circuitry monitors one or more inverter feedback signals and generates in response thereto inverter drive signals that operate the upper and lower switches of the plurality of half bridges in a phase staggered manner and monitors one or more rectifier feedback signals and generates in response thereto rectifier drive signals that operate one or more switches of the rectifying bridge.