Two-switch switched-capacitor converters

Patent metadata

Field	Value
Publication number	US-10075067-B2
Application number	US-201514659216-A
Country	US
Kind code	B2
Filing date	Mar 16, 2015
Priority date	Mar 16, 2014
Publication date	Sep 11, 2018
Grant date	Sep 11, 2018

Abstract

Various examples are provided for two-switch switched-capacitor (SC) converters. In one example, a SC converter includes first and second switches connected in series, a first gain-extension network coupled to the first switch and a second gain-extension network coupled to the second switch, which can be operated to boost a voltage applied across the first and second switches. The gain-extension networks can include a diode and a capacitor. In another example, the gain-extension networks can include a switch and a capacitor, which can be operated to buck a voltage applied across the gain-extension networks. In another example, a SC converter includes first and second diodes connected in series, a first gain-extension network coupled to the first diode and a second gain-extension network coupled to the second diode. The gain-extension networks can include a switch and a capacitor, which can be operated to buck a voltage applied across the gain-extension networks.

First claim

Therefore, at least the following is claimed:

1. A two-switch boosting switched-capacitor converter, comprising:
a first switch and a second switch connected in series across a low side input;
a first gain-extension network connected between a first end and a second end of the first switch, the first gain-extension network consisting of:
a first diode, having a first end and a second end, connected at its first end to the first end of the first switch, and
a first capacitor connected between the second end of the first switch and the second end of the first diode, where the first diode is forward biased from the first end of the first diode to the second end of the first diode;

a second gain-extension network connected between a first end and a second end of the second switch, the second gain-extension network consisting of:
a second diode, having a first end and a second end, connected at its first end to the first end of the second switch, and
a second capacitor connected between the second end of the second switch and the second end of the second diode, where the second diode is forward biased from the second end of the second diode to the first end of the second diode;

wherein the series connection between the second end of the first switch and the second end of the second switch is only connected to the first capacitor and the second capacitor; and
wherein interleaved operation of the first and second switches causes a voltage applied across the first and second switches at the low side input to be boosted at a load.

2. The two-switch boosting switched-capacitor converter of claim 1 , wherein the second end of the first and second diodes are coupled to a high side output.

3. The two-switch boosting switched-capacitor converter of claim 2 , wherein interleaved operation of the first and second switches with a duty ratio of about 0.5 boosts the voltage supplied across the first and second switches by a factor of about two.

4. The two-switch boosting switched-capacitor converter of claim 2 , further comprising an output filter coupled across the high side output.

5. The two-switch boosting switched-capacitor converter of claim 1 , further comprising an input filter coupled across the low side input.

6. The two-switch boosting switched-capacitor converter of claim 1 , further comprising:
a third gain-extension network coupled to the first gain-extension network, the third gain extension network consisting of:
a third diode connected at a first end to the second end of the first diode in the first gain-extension network, and
a third capacitor connected between a second end of the third diode in the third gain-extension network and the connection between the first end of the first switch and the first end of the first diode of the first gain-extension network; and

a fourth gain-extension network consisting of:
a fourth diode connected at a first end to the second end of the second diode in the second gain-extension network, and
a fourth capacitor connected between a second end of the fourth diode in the fourth gain-extension network and the connection between the first end of the second switch and the first end of the second diode of the second gain-extension network.

7. The two-switch boosting switched-capacitor converter of claim 6 , wherein interleaved operation of the first and second switches with a duty ratio of about 0.5 boosts the voltage supplied across the first and second switches by a factor of about three.

8. The two-switch boosting switched-capacitor converter of claim 1 , comprising a plurality of n pairs of gain-extension networks including:
a first series of n gain-extension networks comprising the first gain-extension network coupled to the first switch opposite the second switch and a plurality of subsequent gain-extension networks having corresponding diodes connected in series with the first diode of the first gain-extension network, where each of the plurality of subsequent gain-extension networks in the first series comprise a capacitor connected across the corresponding diode of that gain-extension network and the corresponding diode of a preceding gain-extension network in the first series; and
a second series of n gain-extension networks comprising the second gain-extension network coupled to the second switch opposite the first switch and a plurality of subsequent gain-extension networks having corresponding diodes connected in series with the second diode of the second gain-extension network, where each of the plurality of subsequent gain-extension networks in the second series comprise a capacitor connected across the corresponding diode of that gain-extension network and the corresponding diode of a preceding gain-extension network in the second series.

9. The two-switch boosting switched-capacitor converter of claim 8 , wherein interleaved operation of the first and second switches with a duty ratio of about 0.5 boosts the voltage supplied across the first and second switches by a factor of about n+1, wherein n is the number of pairs of gain-extension networks.

10. A bucking switched-capacitor converter, comprising:
a first diode and a second diode connected in series across a low side output, where a first end of the first diode is connected to a second end of the second diode;
a first gain-extension network connected between the first end of the first diode and a second end of the first diode, the first gain-extension network consisting of:
a first switch, having a first end and a second end, connected at its second end to the second end of the first diode, and
a first capacitor connected between the first end of the first switch and the first end of the first diode, where the first diode is forward biased from the first end of the first diode to the second end of the first diode;

a second gain-extension network connected between a first end of the second diode and the second end of the second diode, the second gain-extension network consisting of:
a second switch, having a first end and a second end, connected at its first end to the first end of the second diode, and
a second capacitor connected between the second end of the second switch and the second end of the second diode, where the second diode is forward biased from the first end of the second diode to the second end of the second diode;

wherein the first diode excludes another switch connected in parallel across its first end and second end;
wherein the second diode excludes another switch connected in parallel across its first end and second end;
wherein the series connection between the first end of the first diode and the second end of the second diode is only connected to the first capacitor and the second capacitor; and
wherein interleaved operation of the first and second switches of the first and second gain-extension networks bucks a voltage applied across the first and second gain-extension networks via a high side input.

11. The bucking switched-capacitor converter of claim 10 , comprising a plurality of n pairs of gain-extension networks including:
a first series of n gain-extension networks comprising the first gain-extension network coupled to the first diode and a plurality of subsequent gain-extension networks having corresponding switches connected in series with the first switch of the first gain-extension network, where each of the plurality of subsequent gain-extension networks in the first series comprise a capacitor connected across the corresponding switch of that gain-extension network and the corresponding switch of a preceding gain-extension network in the first series; and
a second series of n gain-extension networks comprising the second gain-e

Assignees

• Univ California
• Univ Ramot

Inventors

• Wu Bin
• Smedley Keyue Ma
• Singer Sigmond

Classifications

• H02M2003/072

  Electricity · mapped topic

• H02M3/07 Primary

  using capacitors charged and discharged alternately by semiconductor devices with control electrode {, e.g. charge pumps} · CPC title

• H02M3/072

  adapted to generate an output voltage whose value is lower than the input voltage · CPC title