Circuit for generating a voltage waveform

• US 9,461,629 B2
• Filed: 06/29/2015
• Issued: 10/04/2016
• Est. Priority Date: 05/23/2013
• Status: Active Grant

• Current Assignee: Shimadzu Corporation
• Original Assignee: Shimadzu Corporation
• Inventors: Taylor, Steven Douglas, Gill, Matthew Clive, Ding, Li, Nuttall, James Edward
• Primary Examiner(s): Donovan, Lincoln
• Assistant Examiner(s): RETEBO, METASEBIA T
• Application Number:
  US14/754,127
• Publication Number:
  US 20150341020A1
• Time in Patent Office: 463 Days
• Field of Search: 327/124
• US Class Current: 1/1
• CPC Class Codes: H01J 49/022 Circuit arrangements, e.g. for generating deviation currents or voltages regulating electric or magnetic variables in general, e.g. current, magnetic field G05F; Components associated with high voltage supply high voltage supply per se H02M
• CPC Class Codes: H02M 7/4815 Resonant converters H02M7/4811 and H02M7/4826 take precedence
• CPC Class Codes: H02M 7/537 using semiconductor devices only, e.g. single switched pulse inverters
• CPC Class Codes: H03K 17/6871 the output circuit comprising more than one controlled field-effect transistor
• CPC Class Codes: H03K 17/6874 in a symmetrical configuration
• CPC Class Codes: H03K 3/012 Modifications of generator to improve response time or to decrease power consumption
• CPC Class Codes: H03K 3/356 Bistable circuits
• CPC Class Codes: H03K 5/00006 Changing the frequency modulating pulses H03K7/00; frequency dividers H03K21/00 - H03K29/00; additive or subtractive mixing of two pulse rates into one G06F7/605; pulse rate dividers G06F7/68
• CPC Class Codes: Y02B 70/10 Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes

Abstract

A circuit for generating a voltage waveform at an output node. The circuit includes a voltage rail connected to the output node via a voltage rail switch; an anchor node connected to the output node via an inductor and a bidirectional switch, wherein the bidirectional switch includes two or more transistors connected in series; and a control unit configured to change the voltage at the output node by controlling the voltage rail switch and the bidirectional switch so that, if a load capacitance is connected to the output node, a resonant circuit is established between the inductor and the load capacitance. The circuit may be included in an apparatus for use in processing charged particles, e.g. for use in performing mass spectrometry or ion mobility spectrometry.

Claims

1. A mass spectrometer including:

a circuit for generating a voltage waveform that switches between a first voltage and a second voltage at an output node and an additional voltage waveform at an additional output node, wherein the circuit includes;

a voltage rail connected to the output node via a voltage rail switch and connected to the additional output node via an additional voltage rail switch;

a shared inductor;

a shared bidirectional switch, wherein the additional output node is connected to the output node via the shared inductor and the shared bidirectional switch and the output node is connected to the additional output node via the shared inductor and the shared bidirectional switch;

a load capacitance connected between the output node and the additional output node; and

a control unit;

wherein the control unit is configured to change the voltage at the output node by controlling the first voltage rail switch and the shared bidirectional switch connected to the additional output node so that a resonant circuit is established between the shared inductor connected to the additional output node and the load capacitance; and

wherein the control unit is configured to change the voltage at the additional output node by controlling the additional voltage rail switch and the shared bidirectional switch connected to the output node so that a resonant circuit is established between the shared inductor connected to the output node and the load capacitance; and

wherein the control unit is configured to change the frequency at which the switching voltage waveform switches between the first voltage and the second voltage.

2. A mass spectrometer according to claim 1, wherein the shared bidirectional switch includes two or more transistors connected in series, wherein the two or more transistors connected in series include a pair of MOSFET transistors connected back-to-back.

3. A circuit mass spectrometer according to claim 1, wherein:

the voltage rail is a first voltage rail, the voltage rail switch is a first voltage rail switch and the additional voltage rail switch is an additional first voltage rail switch;

the circuit includes a second voltage rail connected to the output node via a second voltage rail switch and connected to the additional output node via an additional second voltage rail switch;

wherein the control unit is configured to change the voltage at the output node by controlling the first voltage rail switch, the second voltage rail switch and the shared bidirectional switch connected to the additional output node so that a resonant circuit is established between the shared inductor connected to the additional output node and the load capacitance; and

wherein the control unit is configured to change the voltage at the additional output node by controlling the additional first voltage rail switch, the additional second voltage rail switch and the shared bidirectional switch connected to the output node so that a resonant circuit is established between the shared inductor connected to the output node and the load capacitance.

4. A mass spectrometer according to claim 1, wherein the circuit is included in an apparatus for use in processing charged particles.

5. A circuit mass spectrometer according to claim 4, wherein the load capacitance includes:

at least one first electrode to which the output node of the circuit is connected so that, in use, the at least one first electrode receives a voltage waveform generated by the circuit;

at least one second electrode to which the additional output node of the circuit is connected so that, in use, the at least one load capacitance receives an additional voltage waveform generated by the circuit.

6. A mass spectrometer according to claim 1, wherein the control unit of the circuit is configured to control the circuit to operate according to a control method including:

closing the first voltage rail switch and opening the shared bidirectional switch so that the output node is clamped at the voltage of the first voltage rail and the additional output node is held at a floating voltage;

causing the voltage at the output node to swing towards the floating voltage and the voltage at the additional output node to swing towards the voltage of the first voltage rail by opening the first voltage rail switch and closing the shared bidirectional switch so that a resonant circuit is established between the inductor and the load capacitance;

closing the additional first voltage rail switch and opening the shared bidirectional switch so that the output node is held at a floating voltage and the additional output node is clamped at the voltage of the first voltage rail;

causing the voltage at the output node to swing towards the voltage of the first voltage rail and the voltage at the additional output node to swing towards the floating voltage by opening the additional first voltage rail switch and closing the shared bidirectional switch so that a resonant circuit is established between the inductor and the load capacitance.

7. A mass spectrometer according to claim 3, wherein the control unit of the circuit is configured to control the circuit to operate according to a control method including:

closing the first voltage rail switch, closing the additional second voltage rail switch and opening the shared bidirectional switch so that the output node is clamped at the voltage of the first voltage rail and the additional output node is clamped at the voltage of the second voltage rail;

causing the voltage at the output node to swing towards the voltage of the second voltage rail and the voltage at the additional output node to swing towards the voltage of the first voltage rail by opening the first voltage rail switch, opening the additional second voltage switch and closing the shared bidirectional switch so that a resonant circuit is established between the inductor and the load capacitance;

closing the second voltage rail switch, closing the additional first voltage rail switch and opening the shared bidirectional switch so that the output node is clamped at the voltage of the second voltage rail and the additional output node is clamped at the voltage of the first voltage rail;

causing the voltage at the output node to swing towards the voltage of the first voltage rail and the voltage at the additional output node to swing towards the voltage of the second voltage rail by opening the second voltage rail switch, opening the additional first voltage rail switch and closing the shared bidirectional switch so that a resonant circuit is established between the inductor and the load capacitance.

8. A mass spectrometer according to claim 4, wherein the apparatus is the mass spectrometer.

9. A method of controlling a mass spectrometer, wherein the mass spectrometer comprises a circuit for generating a voltage waveform that switches between a first voltage and a second voltage at an output node and an additional voltage waveform at an additional output node that includes:

a voltage rail connected to the output node via a voltage rail switch and connected to the additional output node via an additional voltage rail switch;

a shared inductor;

a shared bidirectional switch, wherein the additional output node is connected to the output node via the shared inductor and the shared bidirectional switch and the output node is connected to the additional output node via the shared inductor and the shared bidirectional switch; and

a load capacitance connected between the output node and the additional output node;

wherein the method includes controlling the circuit to operate according to a control method that includes;

closing the first voltage rail switch and opening the shared bidirectional switch so that the output node is clamped at the voltage of the first voltage rail and the additional output node is held at a floating voltage;

causing the voltage at the output node to swing towards the floating voltage and the voltage at the additional output node to swing towards the voltage of the first voltage rail by opening the first voltage rail switch and closing the shared bidirectional switch so that a resonant circuit is established between the inductor and the load capacitance;

closing the additional first voltage rail switch and opening the shared bidirectional switch so that the output node is held at a floating voltage and the additional output node is clamped at the voltage of the first voltage rail;

causing the voltage at the output node to swing towards the voltage of the first voltage rail and the voltage at the additional output node to swing towards the floating voltage by opening the additional first voltage rail switch and closing the shared bidirectional switch so that a resonant circuit is established between the inductor and the load capacitance;

wherein the method also includes changing the frequency at which the switching voltage waveform switches between the first voltage and the second voltage.

10. A method of controlling a mass spectrometer, wherein the mass spectrometer comprises a circuit for generating a voltage waveform that switches between a first voltage and a second voltage at an output node and an additional voltage waveform at an additional output node that includes:

a first voltage rail connected to the output node via a first voltage rail switch and connected to the additional output node via an additional first voltage rail switch;

a second voltage rail connected to the output node via a second voltage rail switch and connected to the additional output node via an additional second voltage rail switch;

a shared inductor;

a shared bidirectional switch, wherein the additional output node is connected to the output node via the shared inductor and the shared bidirectional switch and the output node is connected to the additional output node via the shared inductor and the shared bidirectional switch; and

a load capacitance connected between the output node and the additional output node;

wherein the method includes controlling the circuit to operate according to a control method that includes;

closing the first voltage rail switch, closing the additional second voltage rail switch and opening the shared bidirectional switch so that the output node is clamped at the voltage of the first voltage rail and the additional output node is clamped at the voltage of the second voltage rail;

causing the voltage at the output node to swing towards the voltage of the second voltage rail and the voltage at the additional output node to swing towards the voltage of the first voltage rail by opening the first voltage rail switch, opening the additional second voltage switch and closing the shared bidirectional switch so that a resonant circuit is established between the inductor and the load capacitance;

closing the second voltage rail switch, closing the additional first voltage rail switch and opening the shared bidirectional switch so that the output node is clamped at the voltage of the second voltage rail and the additional output node is clamped at the voltage of the first voltage rail;

causing the voltage at the output node to swing towards the voltage of the first voltage rail and the voltage at the additional output node to swing towards the voltage of the second voltage rail by opening the second voltage rail switch, opening the additional first voltage rail switch and closing the shared bidirectional switch so that a resonant circuit is established between the inductor and the load capacitance;

wherein the method also includes changing the frequency at which the switching voltage waveform switches between the first voltage and the second voltage.

11. A computer-readable medium having computer-executable instructions configured to control a mass spectrometer, wherein the mass spectrometer comprises a circuit for generating a voltage waveform that switches between a first voltage and a second voltage at an output node and an additional voltage waveform at an additional output node that includes:

a voltage rail connected to the output node via a voltage rail switch and connected to the additional output node via an additional voltage rail switch;

a shared inductor;

a shared bidirectional switch, wherein the additional output node is connected to the output node via the shared inductor and the shared bidirectional switch and the output node is connected to the additional output node via the shared inductor and the shared bidirectional switch; and

a load capacitance connected between the output node and the additional output node;

wherein the computer-executable instructions are configured to control the circuit to operate according to a control method that includes;

closing the first voltage rail switch and opening the shared bidirectional switch so that the output node is clamped at the voltage of the first voltage rail and the additional output node is held at a floating voltage;

causing the voltage at the output node to swing towards the floating voltage and the voltage at the additional output node to swing towards the voltage of the first voltage rail by opening the first voltage rail switch and closing the shared bidirectional switch so that a resonant circuit is established between the inductor and the load capacitance;

closing the additional first voltage rail switch and opening the shared bidirectional switch so that the output node is held at a floating voltage and the additional output node is clamped at the voltage of the first voltage rail;

causing the voltage at the output node to swing towards the voltage of the first voltage rail and the voltage at the additional output node to swing towards the floating voltage by opening the additional first voltage rail switch and closing the shared bidirectional switch so that a resonant circuit is established between the inductor and the load capacitance;

wherein the computer-executable instructions are also configured to change the frequency at which the switching voltage waveform switches between the first voltage and the second voltage.

12. A computer-readable medium having computer-executable instructions configured to control a mass spectrometer, wherein the mass spectrometer comprises a circuit for generating a voltage waveform that switches between a first voltage and a second voltage at an output node and an additional voltage waveform at an additional output node that includes:

a first voltage rail connected to the output node via a first voltage rail switch and connected to the additional output node via an additional first voltage rail switch;

a second voltage rail connected to the output node via a second voltage rail switch and connected to the additional output node via an additional second voltage rail switch;

a shared inductor;

a shared bidirectional switch, wherein the additional output node is connected to the output node via the shared inductor and the shared bidirectional switch and the output node is connected to the additional output node via the shared inductor and the shared bidirectional switch; and

a load capacitance connected between the output node and the additional output node;

wherein the computer-executable instructions are configured to control the circuit to operate according to a control method that includes;

closing the first voltage rail switch, closing the additional second voltage rail switch and opening the shared bidirectional switch so that the output node is clamped at the voltage of the first voltage rail and the additional output node is clamped at the voltage of the second voltage rail;

causing the voltage at the output node to swing towards the voltage of the second voltage rail and the voltage at the additional output node to swing towards the voltage of the first voltage rail by opening the first voltage rail switch, opening the additional second voltage switch and closing the shared bidirectional switch so that a resonant circuit is established between the inductor and the load capacitance;

closing the second voltage rail switch, closing the additional first voltage rail switch and opening the shared bidirectional switch so that the output node is clamped at the voltage of the second voltage rail and the additional output node is clamped at the voltage of the first voltage rail;

causing the voltage at the output node to swing towards the voltage of the first voltage rail and the voltage at the additional output node to swing towards the voltage of the second voltage rail by opening the second voltage rail switch, opening the additional first voltage rail switch and closing the shared bidirectional switch so that a resonant circuit is established between the inductor and the load capacitance;

wherein the computer-executable instructions are also configured to change the frequency at which the switching voltage waveform switches between the first voltage and the second voltage.