Fast start charge pump for voltage regulators
View Patent ↗A digital multilevel memory system includes a charge pump and a voltage regulator for generating regulated high voltages for various memory operations. The charge pump may include a plurality of boost circuits to boost the output of the charge pump during a fast start up. Afterwards, the boost circuits are disabled to allow the charge pump to generate high voltages without boosting. The boost circuits may be successively enabled to boost the voltage. The boost circuits may be loadless. The voltage regulator may operate in an open loop and may include a resistive divider as a reference voltage for regulating the high voltage from the charge pump. The charge pump may include spread spectrum pump clocking to reduce electromagnetic inference for capacitor or inductor on-chip charge pumping.
1. An on-chip charge pump system comprising:
a charge pump circuit comprising an output stage;
a dithering pumping clock having a frequency;
a random number generator for varying the frequency; and
a boost circuit comprising a plurality of capacitors coupled to an output of the output stage;
a voltage algorithm controller for successively applying a voltage to each of the plurality of capacitors to boost the voltage of the output;
wherein the voltage of the output is affected by the dithering pumping clock and the boost circuit.
2. The on-chip charge pump system of claim 1 , wherein the capacitors are capable of successively boosting the voltage of the output in steps of two nanoseconds.
3. The on-chip charge pump system of claim 2 , wherein the successive boosting is in response to address transition detection.
4. The on-chip charge pump system of claim 3 wherein said boosting is in response to an address transition and after switching of an address decoder.
5. An on-chip charge pump system comprising:
a charge pump circuit comprising an output stage;
a spread spectrum pumping clock having a charge pump frequency that is biased by a random number generator;
a circuit for modulating the frequency of a cyclic period which is a multiple of the charge pump frequency, over a triangular shape; and
a boost circuit comprising a plurality of capacitors coupled to an output of the output stage and a voltage algorithm controller for successively applying a voltage to each of the plurality of capacitors to boost the voltage of the output, wherein the voltage of the output is affected by the charge pump frequency and the boost circuit.
6. The on-chip charge pump system of claim 5 , further comprising an on-chip inductor.
7. The on-chip charge pump system of claim 5 , wherein the capacitors are capable of successively boosting the voltage of the output in steps of two nanoseconds.
8. The on-chip charge pump system of claim 7 , wherein the successive boosting is in response to address transition detection.
9. The on-chip charge pump system of claim 8 , wherein said boosting is in response to an address transition and after switching of an address decoder.