Efficient CMOS DC-DC converters based on switched capacitor power supplies with inductive current limiters

A DC to DC power converter comprising:

• an input terminal for receiving an input voltage;
• a charging inductor;
• an output terminal for outputting an output voltage different from said input voltage;
• a first capacitor;
• and
• a switch circuit operating at a switching frequency permitting said charging inductor to have an inductance value less than 1 micro Henry, said switch circuit coupling said input terminal to said first capacitor through said charging inductor during a charging phase, said first capacitor being charged during said charging phase, said switch circuit coupling said first capacitor to said output terminal during a transfer phase whereby said first capacitor transfers charge to said output terminal.

A DC to DC converter, comprising:

• a charge transfer capacitor;
• a terminal for receiving a DC source voltage;
• a ground connection;
• a first inductive circuit coupled to said terminal;
• a second inductive circuit;
• an output capacitor coupled between said second inductive circuit and said ground connection;
• a switch circuit operative in a first mode to couple said terminal through said first inductive circuit to a first plate of said charge transfer capacitor and to couple said ground connection to a second plate of said charge transfer capacitor to enable said charge transfer capacitor to be charged by a DC voltage applied to said terminal, said switch circuit being operative in a second mode to couple said first plate of said charge transfer capacitor to said second inductive circuit and to couple said second plate of said charge transfer capacitor to said terminal to enable said output capacitor to be charged by an additive DC voltage formed by a DC voltage at said terminal and a DC voltage on said charge transfer capacitor.

A DC to DC converter, comprising:

• a charge transfer capacitor;
• a terminal for receiving a DC source voltage;
• a ground connection;
• a first inductive circuit coupled to said terminal;
• a second inductive circuit;
• an output capacitor coupled between said second inductive circuit and said ground connection;
• a switch circuit operative in a first mode to couple said terminal through said first inductive circuit to a first plate of said charge transfer capacitor and to couple said ground connection to a second plate of said charge transfer capacitor to enable said charge transfer capacitor to be charged by a DC voltage applied to said terminal, said switch circuit being operative in a second mode to couple said first plate of said charge transfer capacitor to said ground connection and to couple said second plate of said charge transfer capacitor to said second inductive circuit to enable said output capacitor to be charged by a DC voltage on said charge transfer capacitor.

A processor-based system comprising:

• a processor;
• and
• an integrated circuit coupled to said processor, at least one of said processor and said integrated circuit containing a DC power converter comprising:
• an input terminal for receiving an input voltage;
• a charging inductor;
• an output terminal for outputting an output voltage different from said input voltage;
• a first capacitor;
• and
• a switch circuit operating at a switching frequency of at least about 100 MHz for coupling said input terminal to said first capacitor through said charging inductor during a charging phase, said first capacitor being charged during said charging phase,
• said switch circuit coupling said first capacitor to said output terminal during a transfer phase whereby said first capacitor transfers charge to said output terminal.

A processor-based system comprising:

• a processor;
• and
• an integrated circuit coupled to said processor, at least one of said processor and said integrated circuit containing a DC power converter comprising:
• an input terminal for receiving an input voltage;
• a charging inductor;
• an output terminal for outputting an output voltage different from said input voltage;
• a first capacitor;
• and
• a switch circuit operating at a switching frequency permitting said charging inductor to have an inductance value less than 1 micro Henry, said switch circuit coupling said input terminal to said first capacitor through said charging inductor during a charging phase, said first capacitor being charged during said charging phase,
• said switch circuit coupling said first capacitor to said output terminal during a transfer phase whereby said first capacitor transfers charge to said output terminal.

A method of voltage conversion, comprising the acts of:

• receiving an input voltage from an input terminal;
• outputting an output voltage different from said input voltage to an output terminal;
• charging a first capacitor from said input terminal through a charging inductor during a charging phase;
• transferring charge from said first capacitor to said output terminal during a transfer phase;
• and
• alternating between said charging phase and said transfer phase at a switching frequency of about at least 100 MHz using a switch circuit, said switch circuit coupling said input terminal to said first capacitor through said charging inductor during said charging phase, and coupling said first capacitor to said output terminal during said transfer phase.

A DC power converter comprising:

• an input terminal for receiving an input voltage;
• a charging inductor;
• an output terminal for outputting an output voltage different from said input voltage;
• a first capacitor;
• and
• a switch circuit operating at a switching frequency of at least about 100 MHz for coupling said input terminal to said first capacitor through said charging inductor during a charging phase, said first capacitor being charged during said charging phase, said switch circuit coupling said first capacitor to said output terminal and uncoupling said first capacitor from said input terminal during a transfer phase whereby said first capacitor transfers charge to said output terminal;
• wherein said switch circuit includes a first switch connected to open or close a first connection between said input terminal and a first plate of said first capacitor, a second switch connected to open or close a second connection between said first plate and said output terminal, a third switch connected to open or close a third connection between a second plate of said first capacitor and a ground potential, and a fourth switch connected to open or close a fourth connection between said second plate and said input terminal.

A DC power converter comprising:

• an input terminal for receiving an input voltage;
• a charging inductor;
• an output terminal for outputting an output voltage different from said input voltage;
• a first capacitor;
• and
• a switch circuit operating at a switching frequency of at least about 100 MHz for coupling said input terminal to said first capacitor through said charging inductor during a charging phase, said first capacitor being charged during said charging phase,
• said switch circuit coupling said first capacitor to said output terminal during a transfer phase whereby said first capacitor transfers charge to said output terminal;
• wherein during said charging phase, said switch circuit connects said input terminal to a positive plate of said first capacitor and a negative plate of said first capacitor to a ground potential, and during said transfer phase, said switch circuit connects said negative plate to said input terminal and said positive plate to said output terminal.

A DC power converter comprising:

• an input terminal for receiving an input voltage;
• a charging inductor;
• an output terminal for outputting an output voltage different from said input voltage;
• a first capacitor;
• and
• a switch circuit operating at a switching frequency of at least about 100 MHz for coupling said input terminal to said first capacitor through said charging inductor during a charging phase, said first capacitor being charged during said charging phase,
• said switch circuit coupling said first capacitor to said output terminal during a transfer phase whereby said first capacitor transfers charge to said output terminal;
• wherein during said charging phase, said switch circuit connects said input terminal to a positive plate of said first capacitor and a negative plate of said first capacitor to a ground potential, and during said transfer phase, said switch circuit connects said positive plate to said ground potential and said negative plate to said output terminal.

A DC power converter comprising:

• an input terminal for receiving an input voltage;
• a charging inductor;
• an output terminal for outputting an output voltage different from said input voltage;
• a first capacitor;
• a switch circuit operating at a switching frequency of at least about 100 MHz for coupling said input terminal to said first capacitor through said charging inductor during a charging phase, said first capacitor being charged during said charging phase,
• said switch circuit coupling said first capacitor to said output terminal during a transfer phase whereby said first capacitor transfers charge to said output terminal;
• and
• at least a second charging circuit including at least a second capacitor and a second switch circuit connected in parallel with a first charging circuit including at least said first capacitor and said switch circuit, said switch circuits periodically connecting each of said parallel charging circuits to said output terminal.

A DC power converter comprising:

• an input terminal for receiving an input voltage;
• a charging inductor;
• an output terminal for outputting an output voltage different from said input voltage;
• a first capacitor;
• and
• a switch circuit operating at a switching frequency permitting said charging inductor to have an inductance value less than 1 micro Henry, said switch circuit coupling said input terminal to said first capacitor through said charging inductor during a charging phase, said first capacitor being charged during said charging phase,
• said switch circuit coupling said first capacitor to said output terminal during a transfer phase whereby said first capacitor transfers charge to said output terminal;
• wherein said switch circuit includes a first switch connected to open or close a first connection between said input terminal and a positive plate of said first capacitor, a second switch connected to open or close a second connection between said positive plate and said output terminal, a third switch connected to open or close a third connection between a negative plate of said first capacitor and a ground potential, and a fourth switch connected to open or close a fourth connection between said negative plate and said input terminal.

A DC power converter comprising:

• an input terminal for receiving an input voltage;
• a charging inductor;
• an output terminal for outputting an output voltage different from said input voltage;
• a first capacitor;
• and
• a switch circuit operating at a switching frequency permitting said charging inductor to have an inductance value less than 1 micro Henry, said switch circuit coupling said input terminal to said first capacitor through said charging inductor during a charging phase, said first capacitor being charged during said charging phase,
• said switch circuit coupling said first capacitor to said output terminal during a transfer phase whereby said first capacitor transfers charge to said output terminal;
• wherein during said charging phase, said switch circuit connects said input terminal to a positive plate of said first capacitor and a negative plate of said first capacitor to a ground potential, and during said transfer phase, said switch circuit connects said negative plate to said input terminal and said positive plate to said output terminal.

A DC power converter comprising:

• an input terminal for receiving an input voltage;
• a charging inductor;
• an output terminal for outputting an output voltage different from said input voltage;
• a first capacitor;
• and
• a switch circuit operating at a switching frequency permitting said charging inductor to have an inductance value less than 1 micro Henry, said switch circuit coupling said input terminal to said first capacitor through said charging inductor during a charging phase, said first capacitor being charged during said charging phase,
• said switch circuit coupling said first capacitor to said output terminal during a transfer phase whereby said first capacitor transfers charge to said output terminal;
• wherein during said charging phase, said switch circuit connects said input terminal to a positive plate of said first capacitor and a negative plate of said first capacitor to a ground potential, and during said transfer phase, said switch circuit connects said positive plate to said ground potential and said negative plate to said output terminal.

A DC power converter comprising:

• an input terminal for receiving an input voltage;
• a charging inductor;
• an output terminal for outputting an output voltage different from said input voltage;
• a first capacitor;
• and
• a switch circuit operating at a switching frequency permitting said charging inductor to have an inductance value less than 1 micro Henry, said switch circuit coupling said input terminal to said first capacitor through said charging inductor during a charging phase, said first capacitor being charged during said charging phase,
• said switch circuit coupling said first capacitor to said output terminal during a transfer phase whereby said first capacitor transfers charge to said output terminal;
• wherein said charging phase and said transfer phase do not overlap.

A DC power converter comprising:

• an input terminal for receiving an input voltage;
• a charging inductor;
• an output terminal for outputting an output voltage different from said input voltage;
• a first capacitor;
• a switch circuit operating at a switching frequency permitting said charging inductor to have an inductance value less than 1 micro Henry, said switch circuit coupling said input terminal to said first capacitor through said charging inductor during a charging phase, said first capacitor being charged during said charging phase,
• said switch circuit coupling said first capacitor to said output terminal during a transfer phase whereby said first capacitor transfers charge to said output terminal;
• and
• at least a second charging circuit including at least a second capacitor and a second switch circuit connected in parallel with a first charging circuit including at least said first capacitor and said switch circuit, said switch circuits periodically connecting each of said parallel charging circuits to said output terminal.

A DC to DC converter, comprising:

• a charge transfer capacitor;
• a terminal for receiving a DC source voltage;
• a ground connection;
• a first inductive circuit coupled to said terminal;
• a second inductive circuit;
• an output capacitor coupled between said second inductive circuit and said ground connection;
• a switch circuit operative in a first mode to couple said terminal through said first inductive circuit to a first plate of said charge transfer capacitor and to couple said ground connection to a second plate of said charge transfer capacitor to enable said charge transfer capacitor to be charged by a DC voltage applied to said terminal, said switch circuit being operative in a second mode to couple said first plate of said charge transfer capacitor to said second inductive circuit and to couple said second plate of said charge transfer capacitor to said terminal to enable said output capacitor to be charged by an additive DC voltage formed by a DC voltage at said terminal and a DC voltage on said charge transfer capacitor;
• wherein said switch circuit includes a first switch connected to open or close a first connection between said first inductive circuit and said first plate of said charge transfer capacitor, a second switch connected to open or close a second connection between said first plate of said charge transfer capacitor and said second inductive circuit, a third switch connected to open or close a third connection between said second plate of said charge transfer capacitor and said ground connection, and a fourth switch connected to open or close a fourth connection between said second plate of said charge transfer capacitor and said terminal.