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 clock to generate one or more clock signals;
a power converter having a controller, the controller to control at least a deadtime interval based, at least in part, on the clock signals; and
a first circuit to be coupled to an inductor at a terminal thereof, the inductor configured to control a rate of change in electrical charge to flow between the first circuit and the inductor,
wherein, the first circuit to comprise a plurality of switches operable by the controller to facilitate a plurality of fly capacitors cycling through a set of cycles, a particular cycle of the sets of cycles to arrange the plurality of fly capacitors into a particular arrangement of a sequence of arrangements, and
wherein, at the beginning of a subsequent cycle to occur after the particular cycle of the set of cycles, at least one of the fly capacitors is to be charged to a state of charge to be substantially the same as a state of charge to which the at least one fly capacitor was charged at the beginning of the first cycle.
2. The apparatus of claim 1 , wherein the plurality of switches comprises a first switch, a second switch, a third switch, and a fourth switch.
3. The apparatus of claim 2 , wherein:
the first switch is coupled to a reference;
the second switch is coupled to the first switch and the inductor;
the third switch is coupled to the second switch and a first fly capacitor; and
the fourth switch is coupled to the third switch.
4. The apparatus of claim 2 , wherein:
a first fly capacitor is coupled between the second switch and the third switch;
the first switch is coupled to the first fly capacitor and a reference;
the second switch is coupled to the first fly capacitor and the inductor; and
the fourth switch is coupled to the first fly capacitor.
5. The apparatus of claim 1 , wherein the controller to control the sequence of arrangements based, at least in part, on an output of the first circuit.
6. The apparatus of claim 1 , wherein the particular cycle to comprise a first and a second arrangements of the fly capacitors, and wherein the controller to control the second arrangement based, at least in part, on a measurement obtained from the first arrangement.
7. The apparatus of claim 1 , further comprising a capacitor network comprising the plurality of fly capacitors, the capacitor network to be coupled to the plurality of switches in a manner to allow the controller to control arrangements of the capacitor network.
8. The apparatus of claim 7 , wherein the power converter comprises at least three states.
9. The apparatus of claim 8 , wherein:
the power converter comprises a first state, a second state, and a third state;
the controller transitions the capacitor network between the first state and the second state; and
the controller transitions the capacitor network between the second state and the third state.
10. The apparatus of claim 9 , wherein:
a first deadtime occurs between the first state and the second state; and
a second deadtime occurs between the second state and the third state.
11. A power converter, comprising:
a controller coupled to the power converter, wherein the controller is configured to control at least a deadtime interval based, at least in part, on one or more clock signals; and
a first circuit and a circuit configuration coupled to the power converter at a terminal thereof, the circuit configuration comprising an inductor configured to control a rate of change in electrical charge to flow between the first circuit and the inductor,
wherein the power converter comprises at least three states;
wherein the first circuit to comprise a plurality of switches operable by the controller to facilitate a plurality of fly capacitors cycling through a set of cycles, a particular cycle of the sets of cycles to arrange the plurality of fly capacitors into a particular arrangement of a sequence of arrangements, and
wherein, at the beginning of a subsequent cycle to occur after the particular cycle of the set of cycles, at least one of the fly capacitors is to be charged to a state of charge to be substantially the same as a state of charge to which the at least one fly capacitor was charged at the beginning of the first cycle.
12. The power converter of claim 11 , wherein the plurality of switches comprises a first switch, a second switch, a third switch, and a fourth switch.
13. The power converter of claim 12 , wherein:
the first switch is coupled to a reference;
the second switch is coupled to the first switch and the inductor;
the third switch is coupled to the second switch and a first fly capacitor; and
the fourth switch is coupled to the third switch.
14. The power converter of claim 12 , wherein:
a first fly capacitor is coupled between the second switch and the third switch;
the first switch is coupled to the first fly capacitor and a reference;
the second switch is coupled to the first fly capacitor and the inductor; and
the fourth switch is coupled to the first fly capacitor.
15. The power converter of claim 11 , wherein the plurality of switches are coupled in series.
16. The power converter of claim 11 , wherein the controller to control the sequence of arrangements based, at least in part, on an output of the first circuit.
17. The power converter of claim 11 , wherein the particular cycle to comprise first and second arrangements of the fly capacitors, and wherein the controller to control the second arrangement based, at least in part, on a measurement obtained from the first arrangement.
18. The power converter of claim 11 , further comprising a capacitor network comprising the plurality of fly capacitors, the capacitor network to be coupled to the plurality of switches in a manner to allow the controller to control arrangements of the capacitor network.
19. The power converter of claim 18 , wherein:
the power converter comprises a first state, a second state, and a third state;
the controller transitions the capacitor network between the first state and the second state; and
the controller transitions the capacitor network between the second state and the third state.
20. The power converter of claim 18 , wherein:
the power converter comprises a first state, a second state, and a third state;
the controller transitions the capacitor network between the first state and the second state, wherein a first deadtime occurs between the first state and the second state; and
the controller transitions the capacitor network between the second state and the third state, wherein a second deadtime occurs between the second state and the third state.