High voltage resistive output stage circuit
Some embodiments include a high voltage, high frequency switching circuit. The switching circuit may include a high voltage switching power supply that produces pulses having a voltage greater than 1 kV and with frequencies greater than 10 kHz and an output. The switching circuit may also include a resistive output stage electrically coupled in parallel with the output and between the output stage and the high voltage switching power supply, the resistive output stage comprising at least one resistor that discharges a load coupled with the output. In some embodiments, the resistive output stage may be configured to discharge over about 1 kilowatt of average power during each pulse cycle. In some embodiments, the output can produce a high voltage pulse having a voltage greater than 1 kV and with frequencies greater than 10 kHz with a pulse fall time less than about 400 ns.
1. A high voltage, high frequency switching circuit comprising:
a high voltage switching power supply that produces pulses having a voltage greater than 1 kV and with frequencies greater than 10 kHz;
an output; and
a resistive output stage electrically coupled to and in parallel with the output of the high voltage switching power supply and the output, the resistive output stage has a resistance less than about 2000 ohms, the resistive output stage has a capacitance less than about 500 pF, the resistive output stage is configured to discharge a load coupled with the output that has been charged by the pulses from the high voltage switching power supply, and the resistive output stage configured to dissipate over about 1 kilowatt of average power.
2. The high voltage, high frequency switching circuit according to claim 1 , wherein the resistive output stage has a peak power rating greater than 100 kW.
3. The high voltage, high frequency switching circuit according to claim 1 , wherein the resistor in the resistive output stage includes a resistance R and the output is coupled with a load having a capacitance C such that R≈C/t f where t f is the pulse fall time.
4. The high voltage, high frequency switching circuit according to claim 1 , further comprising an inductor coupled in series with the resistive output stage, the inductor having an inductance less than about 300 nH.
5. The high voltage, high frequency switching circuit according to claim 1 , wherein the resistive output stage has an average power rating greater than 1.0 kW.
6. The high voltage, high frequency switching circuit according to claim 1 , wherein the resistive output stage is configured to dissipate charge on the load with a rise time less than about 100 ns.
7. The high voltage, high frequency switching circuit according to claim 1 , wherein the resistive output stage is configured to dissipate charge on the load with a fall time less than about 100 ns.
8. The high voltage, high frequency switching circuit according to claim 1 , wherein the resistive output stage is configured to dissipate charge on the load with pulse widths less than about 250 ns.
9. The high voltage, high frequency switching circuit according to claim 1 , further comprising a switch arranged in series with the resistive output stage.
10. The high voltage, high frequency switching circuit according to claim 9 , wherein the switch is configured to be open when the high voltage switching power supply is producing a pulse, and is closed when the high voltage switching power supply is not producing a pulse.
11. The high voltage, high frequency switching circuit according to claim 1 , further comprising a blocking diode disposed between the high voltage switching power supply and the resistive output stage.
12. A high voltage, high frequency switching circuit comprising:
a high voltage switching power supply that produces pulses having a voltage greater than 1 kV and with frequencies greater than 10 kHz;
an output; and
a resistive output stage electrically coupled to, and in parallel with the high voltage switching power supply and the output, the resistive output stage has a resistance less than about 2000 ohms, the resistive output stage has a capacitance less than about 500 pF, the resistive output stage is configured to discharge a load coupled with the output that has been charged by the pulses from the high voltage switching power supply
wherein the output can produce a high voltage pulse having a voltage greater than 1 kV and with frequencies greater than 10 kHz and with a pulse fall time less than about 400 ns.
13. The high voltage, high frequency switching circuit according to claim 12 , wherein the resistive output stage is configured to dissipate over about 1 kilowatt of power.
14. The high voltage, high frequency switching circuit according to claim 12 , wherein the resistive output stage handles a peak power greater than 10 kW.
15. The high voltage, high frequency switching circuit according to claim 12 , wherein the resistance of the resistor in the resistive output stage is less than about 400 ohms.
16. The high voltage, high frequency switching circuit according to claim 12 , wherein the resistive output stage includes an inductor and a resistor, and wherein the inductance L of the inductor and the resistance R of the resistor are set to satisfy L/R≈tp, where tp is the pulse width of the pulse.
17. The high voltage, high frequency switching circuit according to claim 12 , wherein the resistive output stage includes a resistance R and the output is coupled with a load having a capacitance C such that R≈C/t f where t f is the pulse fall time.
18. The high voltage, high frequency switching circuit according to claim 12 , further comprising an inductor coupled in series with the resistive output stage, the inductor having an inductance less than about 300 nH.
19. The high voltage, high frequency switching circuit according to claim 12 , wherein the resistive output stage is configured to dissipate charge on the load with a rise time less than about 100 ns.
20. The high voltage, high frequency switching circuit according to claim 12 , wherein the resistive output stage is configured to dissipate charge on the load with a fall time less than about 100 ns.
21. The high voltage, high frequency switching circuit according to claim 12 , wherein the resistive output stage is configured to dissipate charge on the load with pulse widths less than about 250 ns.
22. The high voltage, high frequency switching circuit according to claim 12 , further comprising a switch arranged in series with the resistive output stage, wherein the switch is configured to be open when the high voltage switching power supply is producing a pulse, and is closed when the high voltage switching power supply is not producing a pulse.
23. The high voltage, high frequency switching circuit according to claim 12 , further comprising a blocking diode disposed between the high voltage switching power supply and the resistive output stage.
24. A high voltage, high frequency switching circuit comprising:
a high voltage switching power supply that produces pulses having a voltage greater than 1 kV and with frequencies greater than 10 kHz;
an output; and
a resistive output stage electrically coupled to and in parallel with the high voltage switching power supply and the output, the resistive output stage has a resistance less than about 2000 ohms, the resistive output stage has a capacitance less than about 500 pF, the resistive output stage is configured to discharge a load coupled with the output that has been charged by the pulses from the high voltage switching power supply, the resistive output stage comprising at least one resistor,
wherein the output can produce a high voltage pulse having a voltage greater than 1 kV with frequencies greater than 10 kHz and with pulse fall times less than about 400 ns, and wherein the output is electrically coupled to a plasma type load.
25. The high voltage, high frequency switching circuit according to claim 24 , further comprising an inductor coupled in series with the resistive output stage, the inductor having an inductance less than about 300 nH.
26. The high voltage, high frequency switching circuit according to claim 24 , further comprising a switch arranged in series with the resistive output stage.
27. The high voltage, high frequency switching circuit according to claim 24 , further comprising a blocking diode disposed between the high voltage switching power supply and the resistive output stage.
28. The high voltage, high frequency switching circuit according to claim 24 , further comprising a switch arranged in series with the resistive output stage, wherein the switch is configured to be open when the high voltage switching power supply is producing a pulse, and is closed when the high voltage switching power supply is not producing a pulse.