Method and apparatus for digitally regulating an output voltage using noise-shaped component selection
Provided is a digitally-controlled linear regulator having noise-shaped component selection. The digitally-controlled linear regulator has a regulated-voltage sensor, a comparator module, a quantization module, and an impedance switching network. The regulated-voltage sensor is operably coupled to sense an output voltage of the digitally-controlled linear regulator to produce a sensed output voltage. The comparator module is operably coupled to compare the sensed output voltage with a reference voltage at a predetermined clock rate to produce a digital regulation signal. The quantization module is operably coupled to quantize the digital regulation signal to produce a quantized regulation signal. The impedance switching network is operably coupled to convert a source voltage into the output voltage of the digitally-controlled linear regulator based on the quantized regulation signal.
1. A digitally-controlled linear regulator using noise-shaped component selection comprises:
a regulated-voltage sensor operably coupled to sense an output voltage of the digitally-controlled linear regulator to produce a sensed output voltage;
a comparator module operably coupled to compare the sensed output voltage with a reference voltage at a predetermined clock rate to produce a digital regulation signal;
a quantization module operably coupled to quantize the digital regulation signal to produce a quantized regulation signal; and
an impedance switching network operably coupled to convert a source voltage into the output voltage of the digitally-controlled linear regulator based on the quantized regulation signal.
2. The digitally-controlled linear regulator of claim 1 wherein the comparator module comprises:
a comparator operably coupled to compare the sensed output voltage with the reference voltage at the predetermined clock rate to produce a digital stream of comparison data; and
a loop filter operably coupled to the digital stream of comparison data to produce the digital regulation signal.
3. The digitally-controlled linear regulator of claim 2 wherein the quantization module is a sigma-delta modulator.
4. The digitally-controlled linear regulator of claim 1 wherein the impedance switching network comprises:
a selective resistive network to vary the impedance of the network based on the quantized regulation signal.
5. The digitally-controlled linear regulator of claim 1 wherein the impedance
switching network:
a fixed impedance; and
a switch that operably couples and decouples the fixed impedance between the source voltage and the output voltage based on the quantized regulation signal.
6. The digitally-controlled linear regulator of claim 1 wherein the impedance switching network comprises:
a plurality of gated current sources that are selectively activated and deactivated based on the quantized regulation signal.
7. The digitally-controlled linear regulator of claim 1 wherein the impedance switching network is a switched-capacitor network.
8. The digitally-controlled linear regulator of claim 1 is an integrated circuit.
9. A comprehensive system-on-a-chip comprises:
a processing core operably coupled to process input digital data and produce therefrom output digital data;
digital interface circuitry operable coupled to provide the input digital data to the processing core and to receive the output digital data from the processing core;
mixed signal circuitry operably coupled to convert input analog signals into the input digital data and to convert the output digital data into output analog signals; and
digital linear regulator circuitry operably coupled to convert a source voltage into a supply voltage that supplies at least one of: the processing core, the digital interface circuitry, and the mixed signal circuitry, wherein the digital linear regulator circuitry includes:
a regulated-voltage sensor operably coupled to sense an output voltage of the digitally-controlled linear regulator to produce a sensed output voltage;
a comparator module operably coupled to compare the sensed output voltage with a reference voltage at a predetermined clock rate to produce a digital regulation signal;
a quantization module operably coupled to quantize the digital regulation signal to produce a quantized regulation signal; and
an impedance switching network operably coupled to convert a source voltage into the output voltage of the digitally-controlled linear regulator based on the quantized regulation signal.
10. The comprehensive system-on-a-chip of claim 9 wherein the processing core is a digital signal processor.
11. The comprehensive system-on-a-chip of claim 9 wherein the comparator module further comprises:
a comparator operably coupled to compare the sensed output voltage with the reference voltage at the predetermined clock rate to produce a digital stream of comparison data; and
a loop filter operably coupled to the digital stream of comparison data to produce the digital regulation signal.
12. The comprehensive system-on-a-chip of claim 9 wherein the impedance switching network further comprises:
a selective resistive network between the source voltage and the output voltage to vary the impedance of the network based on the quantized regulation signal.
13. The comprehensive system-on-a-chip of claim 9 wherein the impedance switching network further comprises:
a plurality of gated current sources that are selectively activated and deactivated based on the quantized regulation signal.
14. The comprehensive system-on-a-chip of claim 9 wherein the impedance switching network further comprises:
a fixed impedance; and
a switch that operably couples and decouples the fixed impedance between the source voltage and the output voltage.
15. A method of digitally regulating a power source comprises:
sensing an output voltage by a regulated-voltage sensor to produce a sensed output voltage;
comparing the sensed output voltage with a reference voltage at a predetermined clock rate to produce a digital regulation signal;
quantizing the digital regulation signal to produce a quantized regulation signal; and
regulating a source voltage with the quantized regulation signal to provide the output voltage by operably coupling and decoupling an impedance of at least one of a plurality of selectable impedances between the source voltage and the output voltage in accordance with the quantized regulation signal.
16. The method of digitally regulating a power source of claim 15 wherein quantizing the digital regulation signal to produce a quantized regulation signal is performed by a sigma-delta modulator.
17. The method of digitally regulating a power source of claim 15 wherein regulating a source voltage further comprises:
enabling charging of an impedance element by the source voltage in accordance with the quantized regulation signal; and
enabling discharging of the impedance element to a load in accordance with the quantized regulation signal.
18. The method of digitally regulating a power source of claim 15 wherein regulating a source voltage further comprises:
operably coupling and decoupling a gated current source of a plurality of gated current sources between the source voltage and the output voltage in accordance with the quantized regulation signal.