Charge pump stability control
An apparatus for power conversion includes a switching network that controls interconnections between pump capacitors in a capacitor network that has a terminal coupled to a current source, and a charge-management subsystem. In operation, the switching network causes the capacitor network to execute charge-pump operating cycles during each of which the capacitor network adopts different configurations in response to different configurations of the switching network. At the start of a first charge-pump operating cycle, each pump capacitor assumes a corresponding initial state. The charge-management subsystem restores each pump capacitor to the initial state by the start of a second charge-pump operating cycle that follows the first charge-pump operating cycle.
1. An apparatus comprising a switching-network and a control system to control switches in said switching network to cause a set of pump capacitors to cycle through different arrangements of pump capacitors in said set, wherein each cycle begins with an initial arrangement and ends with a final arrangement, wherein said switching network has a terminal connected to a circuit that includes an inductor, wherein, at the start of a first cycle, said pump capacitors are in a state and wherein, at the start of a subsequent cycle that follows said first cycle, said capacitors have been restored to said state, wherein said state corresponds to an extent to which each of said capacitors in said set of pump capacitors is charged.
2. The apparatus of claim 1 , wherein said subsequent cycle starts immediately after said first cycle ends.
3. The apparatus of claim 1 , wherein said inductor is a constituent of a magnetic filter.
4. The apparatus of claim 1 , wherein said inductor is a constituent of a regulator.
5. The apparatus of claim 1 , further wherein said switching network and said capacitor network comprise constituents of charge pump that comprises at least a first stage and a second stage.
6. The apparatus of claim 1 , wherein, between said initial and final arrangements there exists an arrangement in which said pump capacitors are disconnected from each other.
7. The apparatus of claim 1 , wherein said switching network and said capacitor network are configured to form at least a portion of a cascade multiplier.
8. The apparatus of claim 1 , further comprising a circuit that comprises switches and capacitors that, in operation, causes a first voltage at a first terminal thereof to transition into a second voltage, wherein said switching network and set of pump capacitors are constituents of said circuit.
9. The apparatus of claim 1 , wherein said controller controls how long said initial arrangement lasts for and how long said final arrangement lasts for.
10. The apparatus of claim 1 , wherein said inductor is a constituent of a circuit that automatically resists an attempt to change flow of charge therethrough.
11. An apparatus comprising a power converter having a controller and a first circuit that connects to a second circuit at a terminal thereof, said second circuit being configured to sustain resistance to an attempt by said first circuit to change a rate at which electrical charge passes between said first and second circuits, wherein said first circuit comprises a plurality of switches that, in response to control signals from said controller, cause a plurality of pump capacitors to pass through a set of cycles, each of which is characterized by a sequence of arrangements of capacitors, wherein, at the beginning of a subsequent cycle that occurs after a first cycle, at least one of said pump capacitors is charged to an extent that is the same as the extent to which said pump capacitor was charged at the beginning of said first cycle.
12. The apparatus of claim 11 , wherein said controller is configured to control a particular cycle based at least in part on performance of said switching network during at least one of a plurality of cycles that preceded said particular cycle.
13. The apparatus of claim 11 , wherein said controller is configured to cause said cycles have variable time durations.
14. The apparatus of claim 11 , wherein said second circuit is configured to store energy in a magnetic field, said energy being made available on demand for sustaining said resistance.
15. The apparatus of claim 11 , wherein said second circuit comprises a buck converter.
16. The apparatus of claim 11 , wherein a cycle comprises first and second arrangements of said pump capacitors, and wherein said controller controls said second arrangement based on a result of having had said switching network assume said first arrangement.
17. The apparatus of claim 11 , further comprising a capacitor network comprising said pump capacitors, wherein said capacitor network connects to said switching network such that said switching network controls arrangements of said capacitor network.
18. The apparatus of claim 11 , wherein said controller uses feedback to control said arrangements based on an output of said first circuit.
19. The apparatus of claim 11 , wherein said controller causes said switching network to cause said capacitor network to assume a dead-time configuration.
20. The apparatus of claim 11 , wherein said second circuit comprises a regulator.