Power supply for gate driver in switched-capacitor circuit

• US 10,644,590 B2
• Filed: 04/16/2019
• Issued: 05/05/2020
• Est. Priority Date: 03/15/2013
• Status: Active Grant

• Current Assignee: pSemi Corporation (Murata Manufacturing Co Limited)
• Original Assignee: pSemi Corporation (Murata Manufacturing Co Limited)
• Inventors: Giuliano, David, Szczeszynski, Gregory, Barrett, Jr., Raymond
• Primary Examiner(s): Zhang, Jue
• Assistant Examiner(s): Jackson, Lakaisha
• Application Number:
  US16/385,320
• Publication Number:
  US 20190245436A1
• Time in Patent Office: 385 Days
• CPC Class Codes: H02M 1/088 for the simultaneous control of series or parallel connected semiconductor devices
• 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 3/073 Charge pumps of the Schenkel-type

Abstract

An apparatus includes first and second pluralities of switches, a controller for controlling these switches, gate-drivers for driving switches from the first plurality of switches, and first and second terminals configured for coupling to corresponding first and second external circuits at corresponding first and second voltages. During operation, the controller causes the first plurality of switches to transition between states. These transitions result in the second voltage being maintained at a value that is a multiple of the first voltage. The controller also causes the second plurality of switches to transition between states. These transitions resulting in capacitors being coupled or decoupled from the second voltage. The gate drivers derive, from the capacitors, charge for causing a voltage that enables switches from the first plurality of switches to be driven.

Claims

1. An apparatus comprising a first plurality of switches, a second plurality of switches, a controller for controlling said first and second pluralities of switches, gate-drivers for driving switches from said first plurality of switches, and first and second terminals configured for coupling to corresponding first and second external circuits at corresponding first and second voltages, wherein, during operation, said controller causes said first plurality of switches to assume different states, each state being characterized by a switch-activation pattern that defines which switches are to be open and which switches are to be closed during said state, wherein, as a result, said second voltage is maintained at a value that is a multiple of said first voltage, said controller causes said second plurality of switches to transition between successive states, wherein each state is characterized by a switch-activation pattern that defines which switches are to be open and which switches are to be closed during said state, wherein, as a result, capacitors are coupled or decoupled from said second voltage, wherein said gate drivers derive, from said capacitors, charge for causing a voltage that enables switches from said first plurality of switches to be driven.

2. The apparatus of claim 1, wherein each switch in said first plurality of switches has a maximum voltage rating that is less than whichever of said first and second voltages is greater.

3. The apparatus of claim 1, wherein a first gate-driver from said gate drivers comprises first and second power connections, wherein a voltage difference between said first and second power connections is less than or equal to twice the lower of said first and second voltages.

4. The apparatus of claim 1, wherein a first gate-driver from said gate drivers comprises a first power-connection and a second power-connection, wherein said first power connection is coupled to one of said capacitors such that a voltage difference between said first and second power connections is less than whichever of said first and second voltages has a higher magnitude.

5. The apparatus of claim 1, wherein said switches in said second plurality of switches are implemented by transistors, each of which has a gate voltage and a source voltage, said apparatus further comprising a resistor divider that is coupled to said second plurality of switches.

6. The apparatus of claim 1, further comprising a resistor divider that is coupled to said second plurality of switches, wherein said switches in said second plurality of switches are implemented by transistors, each of which has a gate voltage and a source voltage, wherein said resistor divider is configured to cause a source voltage of each of said transistors to be at least a threshold voltage below a corresponding gate voltage of said transistor.

7. The apparatus of claim 1, wherein said controller is configured to disable operation of said second plurality of switches after lapse of an interval.

8. The apparatus of claim 1, wherein said switches in said second plurality of switches are implemented by transistors, each of which has a different gate voltage.

9. An apparatus comprising a first switch-set, a controller for controlling switches in said first switch-set, gate-drive circuitry for driving said switches, first and second terminals configured for coupling to corresponding first and second external circuits at corresponding first and second voltages, and nodes for coupling said gate-driving circuitry to a power supply, wherein said power supply comprises capacitors that are constituents of a switched-capacitor network that is coupled to said switches, wherein, during operation, said controller causes said switches in said first switch-set to transition between successive states, each state being characterized by a switch-activation pattern that defines which switches are to be open and which switches are to be closed during said state, said transitions resulting in said second voltage being maintained at a value that is a multiple of said first voltage, wherein said nodes couple said gate-driving circuitry to said capacitors.

10. The apparatus of claim 9, wherein said first switch-set comprises a first switch that lines along a path between anodes of first and second capacitors, wherein a voltage difference across said switch while said switch is open is less than a voltage difference between said anodes of said capacitors.

11. The apparatus of claim 9, wherein said capacitors comprise a first capacitor set and a second capacitor set, said apparatus further comprising a second switch-set that selectively couples said second terminal to capacitors in said first capacitor set while decoupling said second terminal from capacitors in said second capacitor set, wherein, prior to starting steady-state operation of said power supply, said controller causes said switches in said second switch-set to allow said second voltage to drive charge toward said capacitors of said power supply.

12. The apparatus of claim 9, wherein said nodes couple said gate-drive circuitry to anodes of said capacitors.

13. The apparatus of claim 9, wherein during steady-state operation of said power supply, said controller opens said second switches, thereby preventing said second voltage from driving charge toward said capacitors of said power supply.

14. The apparatus of claim 9, wherein said capacitors of said power supply comprise a first capacitor-set and a second capacitor-set, wherein said first set comprises a capacitor having a cathode thereof connected to a phase voltage and said second set comprises a capacitor having a cathode thereof connected to a phase-shifted version of said phase voltage.

15. The apparatus of claim 9, wherein said power supply comprises a cascade multiplier.

16. The apparatus of claim 9, wherein said capacitors comprise a first capacitor and a second capacitor, wherein said gate-drive circuitry comprises first and second gate drives that drive corresponding first and second switches that are in series so that all current passing through said first switch also passes through said second switch, wherein said first switch connects to an anode of a first capacitor and said second switch connects to an anode of a second capacitor.

17. The apparatus of claim 9, wherein said capacitors comprise first and second capacitor sets, said apparatus further comprising a second switch-set that selectively couples said second terminal to capacitors in said first set while decoupling said second terminal from capacitors in said second set.

18. An apparatus comprising a first switch-set, a controller for controlling switches in said first switch-set, gate-drive circuitry for driving said switches, first and second terminals configured for coupling to first and second terminals of a switched-capacitor network that transforms a first voltage into a second voltage so as to provide power to a load, wherein, during operation, said controller causes said switches in said first switch-set to transition between successive states, each state being characterized by a switch-activation pattern that defines which switches are to be open and which switches are to be closed during said state, said transitions resulting in said second voltage being maintained at a value that is a multiple of said first voltage and charge being transferred from said first terminal towards said load, said apparatus further comprising means for diverting charge that is being transferred by said switched-capacitor network towards said load such that efficiency of power transfer to said load is reduced.

19. The apparatus of claim 18, wherein said means for diverting charge is configured to divert said charge towards said gate-drive circuitry.

20. The apparatus of claim 18, wherein said means for diverting charge obtains said charge from capacitors of said switched-capacitor network.