Floating voltage measuring circuit and method

A circuit comprising:

• a first ceramic capacitor having a first terminal and a second terminal;
• a voltage source coupled across the first and second terminals of the first ceramic capacitor;
• a second ceramic capacitor having a first terminal and a second terminal, the first terminal coupled to the first terminal of the first ceramic capacitor, wherein the second ceramic capacitor is substantially identical to the first ceramic capacitor;
• and
• a control circuit configured to apply a second voltage across the first and second terminals of the second ceramic capacitor and to modify the second voltage until a first current passing through the first ceramic capacitor is substantially equal to a second current passing through the second ceramic capacitor.

A method comprising:

• applying a first voltage across terminals of a first ceramic capacitor, the first ceramic capacitor being part of a first branch coupled between a first node and a second node;
• applying a second voltage across terminals of a second ceramic capacitor that is substantially identical to the first ceramic capacitor, the second ceramic capacitor being part of a second branch coupled between the first node and a third node;
• and
• modifying the second voltage until a first current passing through the second node is substantially equal to a second current passing through the third node.