Switching circuit

An RF impedance matching network comprising:

• an RF input configured to couple to an RF source, the RF source having a fixed RF source impedance;
• an RF output configured to couple to a load, the load having a variable load impedance;
• a first circuit comprising a first variable component providing a first variable capacitance or inductance;
• and
• a second circuit comprising a second variable component providing a second variable capacitance or inductance;
• wherein each of the first circuit and the second circuit comprise a plurality of switching circuits configured to provide the first variable capacitance or inductance and the second variable capacitance or inductance, respectively, each of the plurality of switching circuits comprising:
• a passive switch coupled to a first switch terminal;
• a driving switch coupled in series with the passive switch and a second switch terminal, the driving switch configured to turn the passive switch on and off;
• and
• a power source configured to provide power to the passive switch and the driving switch.

A method of controlling a switching circuit, the method comprising:

• providing a switching circuit comprising:
• a passive switch coupled to a first switch terminal;
• a driving switch coupled in series with the passive switch and a second switch terminal, the driving switch configured to turn the passive switch on and off;
• a power source configured to provide power to the passive switch and the driving switch;
• and
• a monitoring circuit;
• receiving at the monitoring circuit (a) an indication that a switching circuit voltage exceeds a predetermined amount or (b) an indication that a switching circuit current exceeds a predetermined amount;
• and
• reducing the power provided to the driving switch in response to the receipt of indication (a) or (b), the reduction of power switching off the switching circuit.