High power switched capacitor voltage conversion and regulation apparatus

• US 5,581,454 A
• Filed: 11/22/1994
• Issued: 12/03/1996
• Est. Priority Date: 11/22/1994
• Status: Expired due to Fees

• Current Assignee: Hansel Collins
• Original Assignee: Hansel Collins
• Inventors: Collins, Hansel
• Primary Examiner(s): Wong, Peter S.
• Assistant Examiner(s): Krishnan, Aditya
• Application Number:
  US08/345,817
• Time in Patent Office: 742 Days
• Field of Search: 363/59, 363/60, 363/62, 363/74, 363/78, 363/79, 323/282, 323/283, 323/285, 307/109, 307/110
• US Class Current: 363/59
• CPC Class Codes: H02M 3/07 using capacitors charged and discharged alternately by semiconductor devices with control electrode , e.g. charge pumps

Abstract

A DC-to-DC voltage convertor is made up of a capacitor array having plural capacitor elements (C_p1, C_p2, C_p3) and a plurality of switches (S2 . . . S10) which are switchable between at least two states. When the switches are switched in the first state, the capacitor elements are connected in series, and when the switches are connected in the second state, the capacitor elements are connected in parallel. The DC-to-DC voltage convertor may be configured as a step-down convertor (FIG. 2a) or a step-up convertor (FIG. 2b).

Claims

1. An integrated step-up/step-down DC-to-DC converter comprising:

a voltage input terminal;

a step-up voltage converter including (a) a first capacitor array including a plurality of capacitor elements, and (b) first switching means for operating in a first mode to connect said first capacitor array to said voltage input terminal and to connect each of said plurality of capacitor elements of said first capacitor array in parallel with each other within said first capacitor array, and in a second mode to connect said first capacitor array to an output of said step-up voltage converter and to connect each of said plurality of capacitor elements of said first capacitor array in series with each other within said first capacitor array;

a step-down voltage converter including (a) a second capacitor array including a plurality of capacitor elements, and (b) second switching means for operating in a third mode to connect said first capacitor array to said output of said step-up voltage converter and to connect each of said plurality of capacitor elements of said second capacitor array in series with each other within said second capacitor array, and in a fourth mode to connect said second capacitor array to an output of said step-down voltage converter and to connect each of said plurality of capacitor elements of said second capacitor array in parallel with each other within said second capacitor array;

a voltage output terminal coupled to said output of said step-down converter.

6. An integrated step-down/step-up DC-to-DC voltage converter as claimed in claim 1, wherein said first and second switching means each includes a plurality of power MOSFETs, respectively, and wherein said converter further comprises:

a gate drive distribution network including a network of series connected capacitors connected to gate terminals of each of said power MOSFETs, the series connected capacitors including at least high-side and low-side drive ports and distributing a gate charge from one of the high-side and low-side ports to each gate terminal of said power MOSFETs;

a port driver circuit connected to said high-side and low-side drive ports of said gate drive distribution network for supplying a gate switching circuit to said power MOSFETs; and

,

means for electrically connecting and disconnecting the gate drive distribution network to and from said gate terminals of said power MOSFETS.

8. A DC-to-DC voltage converter (as claimed in claim 1,) comprising:

a capacitor array including a plurality of capacitor elements; and

,

a plurality of switches which are switchable between at least two states and which are coupled to said plurality of capacitor elements of said capacitor array, wherein said plurality of capacitor elements are connected in series with each other when said plurality of switches are switched in a first state and wherein said plurality of capacitor elements are connected in parallel with each other when said plurality of switches are switched in a second state;

further comprising a symbiotic power circuit for supply power to an input network and an output network of said converter so as to maintain isolation between said input and output networks of said converter, said symbiotic power circuit including first and second stages and means for regulating a flow of charge into said first stage and out of said second stage, and optocouplers for coupling of control signals to said first and second stages so as to maintain electrical isolation of said symbiotic power circuit.

11. A DC-to-DC voltage converter as claimed in claim 1, further comprising a symbiotic power circuit for supply power to an input network and an output network of said converter so as to maintain isolation between said input and output networks of said converter, said symbiotic power circuit including first and second stages and means for regulating a flow of charge into said first stage and out of said second stage, and optocouplers for coupling of control signals to said first and second stages so as to maintain electrical isolation of said symbiotic power circuit.

2. An integrated step-down/step-up DC-to-DC converter comprising:

a voltage input terminal;

a step-down voltage converter including (a) a first capacitor array including a plurality of capacitor elements, and (b) first switching means for operating in a first mode to connect said first capacitor array to said voltage input terminal and to connect each of said plurality of capacitor elements of said first capacitor array in series with each other within said first capacitor array, and in a second mode to connect said first capacitor array to an output of said step-down voltage converter and to connect each of said plurality of capacitor elements of said first capacitor array in parallel to each other within said first capacitor array;

a step-up voltage converter including (a) a second capacitor array including a plurality of capacitor elements, and (b) second switching means for operating in a third mode to connect said second capacitor array to said output of said step-down voltage converter and to connect each of said plurality of capacitor elements of said second capacitor array in parallel to each other within said second capacitor array, and in a fourth mode to connect said second capacitor array to an output of said step-up voltage converter and to connect each of said plurality of capacitor elements of said capacitor array in series with each other within said second capacitor array;

a voltage output terminal coupled to said output of said step-up converter.

7. An integrated step-down/step-up DC-to-DC voltage converter as claimed in claim 2, wherein said first and second switching means each include a plurality of power MOSFETs, respectively, and wherein said converter further comprises:

a gate drive distribution network including a network of series connected capacitors connected to gate terminals of each of said power MOSFETs, the series connected capacitors including at least high-side and low-side drive ports and distributing a gate charge from one of the high-side and low-side ports to each gate terminal of said power MOSFETs;

a port driver circuit connected to said high-side and low-side drive ports of said gate drive distribution network for supplying a gate switching circuit to said power MOSFETs; and

,

means for electrically connecting and disconnecting the gate drive distribution network to and from said gate terminals of said power MOSFETS.

9. A DC-to-DC voltage converter (as claimed in claim 2,) comprising:

a voltage input terminal;

a voltage output terminal;

a capacitor array including a plurality of capacitor elements; and

switching means for operating in a first mode to connect said capacitor array to said voltage input terminal and to connect each of said plurality of capacitor elements of said capacitor array in series with each other within said capacitor array, and in a second mode to connect said capacitor array to said voltage output terminal and to connect each of said plurality of capacitor elements of said capacitor array in parallel with each other within said capacitor array;

further comprising a symbiotic power circuit for supply power to an input network and an output network of said converter so as to maintain isolation between said input and output networks of said converter, said symbiotic power circuit including first and second stages and means for regulating a flow of charge into said first stage and out of said second stage, and optocouplers for coupling of control signals to said first and second stages so as to maintain electrical isolation of said symbiotic power circuit.

12. A DC-to-DC voltage converter as claimed in claim 2, further comprising a symbiotic power circuit for supply power to an input network and an output network of said converter so as to maintain isolation between said input and output networks of said converter, said symbiotic power circuit including first and second stages and means for regulating a flow of charge into said first stage and out of said second stage, and optocouplers for coupling of control signals to said first and second stages so as to maintain electrical isolation of said symbiotic power circuit.

3. A DC-to-DC voltage converter comprising:

a capacitor array including a plurality of capacitor elements; and

,

a plurality of switches which are switchable between at least two states and which are coupled to said plurality of capacitor elements of said capacitor array, wherein said plurality of capacitor elements are connected in series with each other when said plurality of switches are switched in a first state and wherein said plurality of capacitor elements are connected in parallel with each other when said plurality of switches are switched in a second state;

wherein said plurality of switches are power MOSFETs, respectively, and wherein said converter further comprises;

a gate drive distribution network including a network of series connected capacitors connected to gate terminals of each of said power MOSFETs, the series connected capacitors including at least high-side and low-side drive ports and distributing a gate charge from one of the high-side and low-side ports to each gate terminal of said power MOSFETs;

a port driver circuit connected to said high-side and low-side drive ports of said gate drive distribution network for supplying a gate switching circuit to said power MOSFETs; and

,

means for electrically connecting and disconnecting the gate drive distribution network to and from said gate terminals of said power MOSFETS.

5. A step-up DC-to-DC voltage converter (as claimed in claim 3,) comprising:

a voltage input terminal;

a voltage output terminal;

a capacitor array including a plurality of capacitor elements; and

switching means for operating in a first mode to connect said capacitor array to said voltage input terminal and to connect each of said plurality of capacitor elements of said capacitor array in parallel with each other within said capacitor array, and in a second mode to connect said capacitor array to said voltage output terminal and to connect each of said plurality or capacitor elements of said capacitor array in series with each other within said capacitor array;

wherein said switching means each includes a plurality of power MOSFETs, respectively, and wherein said converter further comprises;

a gate drive distribution network including a network of series connected capacitors connected to gate terminals of each of said power MOSFETs, the series connected capacitors including at least high-side and low-side drive ports and distributing a gate charge from one of the high-side and low-side ports to each gate terminal of said power MOSFETs;

a port driver circuit connected to said high-side and low-side drive ports of said gate drive distribution network for supplying a gate switching circuit to said power MOSFETs; and

,

means for electrically connecting and disconnecting the gate drive distribution network to and from said gate terminals of said power MOSFETS.

10. A DC-to-DC voltage converter (as claimed in claim 3,) comprising:

a voltage input terminal;

a voltage output terminal;

a capacitor array including a plurality of capacitor elements; and

switching means for operating in a first mode to connect said capacitor array to said voltage input terminal and to connect each of said plurality of capacitor elements of said capacitor array in parallel with each other within said capacitor array, and in a second mode to connect said capacitor array to said voltage output terminal and to connect each of said plurality of capacitor elements of said capacitor array in series with each other within said capacitor array;

further comprising a symbiotic power circuit for supply power to an input network and an output network of said converter so as to maintain isolation between said input and output networks of said converter, said symbiotic power circuit including first and second stages and means for regulating a flow of charge into said first stage and out of said second stage, and optocouplers for coupling of control signals to said first and second stages so as to maintain electrical isolation of said symbiotic power circuit.

4. A step-down DC-to-DC voltage converter comprising:

a voltage input terminal;

a voltage output terminal;

a capacitor array including a plurality of capacitor elements; and

switching means for operating in a first mode to connect said capacitor array to said voltage input terminal and to connect each of said plurality of capacitor elements of said capacitor array in series with each other within said capacitor array, and in a second mode to connect said capacitor array to said voltage output terminal and to connect each of said plurality of capacitor elements of said capacitor array in parallel with each other within said capacitor array;

wherein said switching means each includes a plurality of power MOSFETs, respectively, and wherein said converter further comprises;

a gate drive distribution network including a network of series connected capacitors connected to gate terminals of each of said power MOSFETs, the series connected capacitors including at least high-side and low-side drive ports and distributing a gate charge from one of the high-side and low-side ports to each gate terminal of said power MOSFETs;

a port driver circuit connected to said high-side and low-side drive ports of said gate drive distribution network for supplying a gate switching circuit to said power MOSFETs; and

,

means for electrically connecting and disconnecting the gate drive distribution network to and from said gate terminals of said power MOSFETS.