Fractional voltage converter

• US 20050259454A1
• Filed: 04/12/2005
• Published: 11/24/2005
• Est. Priority Date: 04/12/2004
• Status: Active Grant

• Current Assignee: Advanced Neuromodulation Systems Incorporated (Abbott Laboratories)
• Original Assignee: Advanced Neuromodulation Systems Incorporated (Abbott Laboratories)
• Inventors: Tranchina, Benjamin A., Varrichio, Anthony J.
• Granted Patent: US 7,180,760 B2
• Time in Patent Office: Days
• US Class Current: 363/61
• CPC Class Codes: A61N 1/36125 Details of circuitry or electric components
• CPC Class Codes: A61N 1/36153 Voltage A61N1/3616 takes precedence
• CPC Class Codes: A61N 1/3782 producing a voltage above the power source level
• CPC Class Codes: H02M 3/07 using capacitors charged and discharged alternately by semiconductor devices with control electrode , e.g. charge pumps
• CPC Class Codes: H02M 3/072 adapted to generate an output voltage whose value is lower than the input voltage

Abstract

Embodiments provide a capacitive voltage multiplier for efficiently producing multiples, including fractional multiples, of a power supply voltage use high, medium and low voltage field effect transistors for switching terminals of various capacitors into and out of connection with power supply or ground voltages in charge mode and with an output or other capacitor terminals for series connection in pump mode. A single non-overlapping clock is level-shifted up to the maximum voltage level required for switching to produce a desired output, then level shifted back down to lower levels with delay added as necessary according to embodiments.

Claims

1. A system comprising:

a capacitive voltage converter accepting input of a digital control signal for selection of a desired voltage level and outputting said desired voltage level, wherein said desired voltage level output comprises fractional multiple of a supply voltage level used by said capacitive voltage converter.

2. The system of claim 1, wherein said capacitive voltage converter comprises:

switching circuitry, wherein said switching circuitry comprises a plurality of controllable switches, wherein said plurality of controllable switches are partitioned in operation of said capacitive voltage converter to minimize a number of components of said capacitive voltage converter experiencing high voltage levels of said plurality of output voltage levels.

3. The system of claim 1, wherein said fractional increments comprise 12 increments of said supply voltage level.

4. The system of claim 1, wherein said system comprises:

a therapeutic stimulation pulse generation system.

5. The system of claim 1, wherein said system comprises:

a high power digital to analog converter that provides voltage level output above said source voltage level.

6. A method comprising:

providing a control signal for selecting a desired voltage level, said desired voltage level being a fractional multiple of a supply voltage level used in generating said desired voltage level; and

switching, under control of said control signal, a plurality of capacitors to generate said desired voltage level.

7. The method of claim 6, wherein said switching comprises:

switching a set of high voltage field effect transistors to establish connections between at least some first components used in producing a first range of voltages, and

switching a set of low voltage field effect transistors to establish connections between at least some second components used in producing a second range of voltages lower than the first range.

8. The method of claim 7, wherein said first components and said second components comprise capacitors of said plurality of capacitors.

9. The method of claim 7, wherein said switching further comprises:

stacking a voltage of said first range of voltages and a voltage of said second range of voltages to generate said desired voltage level.

10. The method of claim 6, wherein said switching said plurality of capacitors occurs upon demand for said desired voltage level.

11. The method of claim 6, wherein said control signal is operable to select said desired voltage level from a range of voltage levels including ½

times said supply voltage level through 3 times said supply voltage level.

12. The method of claim 6, further comprising:

providing said desired voltage level to circuitry delivering a therapeutic stimulation pulse to a patient.

13. The method of claim 12, wherein said desired voltage level is used in selecting a current amplitude of said therapeutic stimulation pulse.

14. The method of claim 6, further comprising:

providing a second control signal for selecting a second desired voltage level; and

switching, under control of said second control signal, said plurality of capacitors to generate said second desired voltage level.

15. The method of claim 14, further comprising:

providing one of said desired voltage level and said second desired voltage level to circuitry delivering a therapeutic stimulation pulse to a patient; and

providing the other one of said desired voltage level and said second desired voltage level to circuitry providing an active discharge pulse.

16. A voltage conversion system comprising:

output voltage level control circuitry; and

a plurality of switchable circuits operating under control of said control circuitry to provide a desired output voltage level, said switchable circuits being controlled by said control circuitry to always dispose lower voltage components of said system to be exposed only to lower voltages of said system and to always dispose higher voltage components of said system to be exposed to higher voltages of said system.

17. The system of claim 16, wherein said voltage conversion system comprises a capacitive voltage multiplier.

18. The system of claim 16, wherein said lower voltage components and said higher voltage components comprise switch circuits.

19. The system of claim 18, wherein said switch circuits comprise field effect transistors of at least two different sizes.

20. The system of claim 16, wherein said lower voltage components and said higher voltage components comprise capacitors.