Configurable multistage charge pump using a supply detect scheme
View Patent ↗A configurable multistage charge pump including multiple pumpcells, at least one bypass switch and control logic. The pumpcells are coupled together in series including a first pumpcell receiving an input voltage and at least one remaining pumpcell including a last pumpcell which generates an output voltage. Each bypass switch is coupled to selectively provide the input voltage to a pumpcell input of a corresponding one of the remaining pumpcells. The control logic is configured to determine one of multiple voltage ranges of the input voltage, to enable each pumpcell for a first voltage range and to disable and bypass at least one pumpcell for at least one other voltage range. A method of operating a multistage charge pump including detecting an input voltage, selecting a voltage range based on an input voltage, and enabling a number of cascaded pumpcells corresponding to the selected voltage range.
1. A configurable multistage charge pump, comprising:
a plurality of pumpcells coupled together in series, comprising a first pumpcell receiving an input voltage and at least one remaining pumpcell, wherein a last one of said at least one remaining pumpcell generates an output voltage;
at least one bypass switch, each coupled to selectively provide said input voltage to a pumpcell input of a corresponding one of said at least one remaining pumpcell; and
control logic, coupled to said plurality of pumpcells and to said at least one bypass switch, configured to determine one of a plurality of voltage ranges of said input voltage, to enable each of said plurality of pumpcells for a first voltage range of said plurality of voltage ranges and to disable and bypass at least one pumpcell for at least one other voltage range of said plurality of voltage ranges, wherein said control logic comprises a comparator which compares a signal indicative of said output voltage with a reference signal and which provides a clock enable signal indicative thereof to a clock enable input of each of said plurality of pumpcells.
2. The configurable multistage charge pump of claim 1 , wherein said control logic disables said first pumpcell and controls a first bypass switch to provide said input voltage to said pumpcell input of a second pumpcell for a second voltage range of said plurality of voltage ranges.
3. The configurable multistage charge pump of claim 2 , wherein said control logic disables said second pumpcell and controls a second bypass switch to provide said input voltage to said pumpcell input of a third pumpcell for a third voltage range of said plurality of voltage ranges.
4. The configurable multistage charge pump of claim 3 , wherein said control logic disables said third pumpcell and controls a third bypass switch to provide said input voltage to said pumpcell input of a fourth pumpcell for a fourth voltage range of said plurality of voltage ranges.
5. The configurable multistage charge pump of claim 1 , wherein said control logic disables each of a set of consecutively coupled pumpcells and controls said at least one bypass switch to provide said input voltage to said pumpcell input of a pumpcell following said set of consecutively coupled pumpcells for said at least one other voltage range of said plurality of voltage ranges.
6. The configurable multistage charge pump of claim 1 , wherein said control logic provides a plurality of bypass signals, each selectively disabling a corresponding pumpcell and controlling a corresponding bypass switch to provide said input voltage to a next pumpcell in series.
7. The configurable multistage charge pump of claim 1 , wherein each of said plurality of pumpcells comprises a switched capacitor for increasing voltage from said pumpcell input to a pumpcell output.
8. A method of operating a multistage charge pump, comprising:
detecting an input voltage;
selecting one of a plurality of voltage ranges based on a level of the input voltage;
enabling a number of a plurality of pumpcells in cascade configuration corresponding to the selected voltage range; and
comparing a signal indicative of an output voltage with a reference signal and providing a clock enable signal indicative thereof to a clock enable input of each of the plurality of pumpcells.
9. The method of claim 8 , wherein said enabling a number of a plurality of pumpcells comprises disabling all but one of the plurality of pumpcells for a highest of the plurality of voltage ranges.
10. The method of claim 8 , further comprising enabling all of the plurality of pumpcells for a lowest of the plurality of voltage ranges.
11. The method of claim 8 , further comprising disabling and bypassing at least one of the plurality of pumpcells based on the selected voltage range.
12. The method of claim 8 , further comprising disabling at least one of the plurality of pumpcells and providing the input voltage to a next one of the plurality of pumpcells in series.
13. The method of claim 8 , further comprising disabling a consecutive set of at least two of the plurality of pumpcells and providing the input voltage to a next one of the plurality of pumpcells in series.
14. The method of claim 8 , further comprising disabling at least one of the plurality of pumpcells by disabling a clock signal.
15. The method of claim 8 , further comprising asserting a bypass signal to disable and bypass a corresponding one of the plurality of pumpcells.
16. The method of claim 8 , further comprising asserting a bypass signal to disable a pumpcell and to control a switch to provide the input voltage to an input of a next pumpcell.
17. The method of claim 8 , wherein said enabling a number of a plurality of pumpcells includes disabling remaining ones of the plurality of pumpcells.
18. The method of claim 8 , further comprising:
disabling all of the plurality of pumpcells when the clock enable signal indicates that the output voltage has reached a predetermined voltage level.
19. A processing system, comprising:
a memory array;
a configurable multistage charge pump system, configured to provide at least one output voltage level to said memory array, wherein selected stages of said multistage charge pump system are bypassed in accordance with a voltage level of an input supply voltage; and
control logic comprising a comparator that compares a signal indicative of said at least one output voltage level with a reference signal and that provides a clock enable signal indicative thereof to a clock input of each of said stages of multistage pump system.