Analog to digital converter having switched capacitor power supply
View Patent ↗An Analog to Digital Converter (ADC) includes an ADC core, a first switched capacitor voltage regulator, and a second switched capacitor voltage regulator. The ADC core includes a plurality of digital components that sample an incoming signal based on an ADC clock, a first voltage, and a first ground and a plurality of analog components configured to operate using a second voltage and a second ground. The first switched capacitor voltage regulator produces the first voltage and the first ground for the plurality of digital components using a supply voltage, a supply ground, and the ADC clock. The second switched capacitor voltage regulator produces the second voltage and the second ground using the supply voltage, the supply ground, and the ADC clock. Switching of the first and second switched capacitor voltage regulators is performed using complementary and non-overlapping clocks having switching frequency that is based upon the ADC clock.
1. An Analog to Digital Converter (ADC) comprising:
an ADC core comprising:
a plurality of digital components configured to sample at least one incoming signal based on an ADC clock, a first voltage, and a first ground; and
a plurality of analog components including at least one amplifier configured to operate using a second voltage and a second ground;
a first switched capacitor voltage regulator configured to produce the first voltage and the first ground using a supply voltage, a supply ground, and the ADC clock; and
a second switched capacitor voltage regulator configured to produce the second voltage and the second ground using the supply voltage, the supply ground, and the ADC clock.
2. The ADC of claim 1 , wherein at least one of the first switched capacitor voltage regulator and the second switched capacitor voltage regulator comprises digital feedback.
3. The ADC of claim 1 , wherein:
the first switched capacitor voltage regulator is configured to produce the first voltage at a voltage greater than the supply voltage; and
the first switched capacitor voltage regulator is configured to produce the first ground at a voltage less than the supply ground.
4. The ADC of claim 1 , wherein:
the second switched capacitor voltage regulator is configured to produce the second voltage at a voltage greater than the supply voltage; and
the second switched capacitor voltage regulator is configured to produce the second ground at a voltage less than the supply ground.
5. The ADC of claim 1 , wherein at least one of the first and the second switched capacitor voltage regulators comprises:
a first switched capacitor circuit comprising:
a first plurality of switches controlled by complementary and non-overlapping clocks;
a first variable capacitor; and
first digital feedback controlling the first variable capacitor; and
a second switched capacitor circuit comprising:
a second plurality of switches controlled by the complementary and non-overlapping clocks;
a second variable capacitor; and
second digital feedback controlling the second variable capacitor.
6. The ADC of claim 5 , wherein a frequency of the complementary and non-overlapping clocks is one of:
equal to the ADC clock;
an integer multiple of the ADC clock; or
a fraction of the ADC clock.
7. The ADC of claim 5 , wherein:
the first digital feedback comprises a first comparator and a first finite state machine; and
the second digital feedback comprises a second comparator and a second finite state machine.
8. An Analog to Digital Converter (ADC) comprising:
an ADC core comprising:
a plurality of digital components configured to sample at least one incoming signal based on an ADC clock, a first voltage and a first ground; and
a plurality of analog components including at least one amplifier configured to operate using a second voltage and a second ground; and
a switched capacitor voltage regulator configured to produce at least one of the first voltage and the second voltage and at least one of the first ground and the second ground using a supply voltage, a supply ground, and the ADC clock.
9. The ADC of claim 8 , wherein the switched capacitor voltage regulator comprises analog feedback for production of the first voltage and the first ground.
10. The ADC of claim 8 , wherein the switched capacitor voltage regulator comprises digital feedback for production of the first voltage and the first ground.
11. The ADC of claim 8 , wherein the switched capacitor voltage regulator includes:
a first switched capacitor circuit comprising:
a first plurality of switches controlled by complementary and non-overlapping clocks;
a first capacitor; and
first analog feedback; and
a second switched capacitor circuit comprising:
a second plurality of switches controlled by the complementary and non-overlapping clocks;
a second capacitor; and
second analog feedback.
12. The ADC of claim 11 , wherein a frequency of the complementary and non-overlapping clocks is one of:
equal to the ADC clock;
an integer multiple of the ADC clock; or
a fraction of the ADC clock.
13. The ADC of claim 11 , wherein:
the first analog feedback comprises a first amplifier; and
the second analog feedback comprises a second amplifier.
14. The ADC of claim 8 , wherein the switched capacitor voltage regulator includes:
a first switched capacitor circuit comprising:
a first plurality of switches controlled by complementary and non-overlapping clocks;
a first variable capacitor; and
first digital feedback controlling the first variable capacitor; and
a second switched capacitor circuit comprising:
a second plurality of switches controlled by the complementary and non-overlapping clocks;
a second variable capacitor; and
second digital feedback controlling the second variable capacitor.
15. The ADC of claim 8 , wherein the switched capacitor voltage regulator is switched by a clock that is one of:
equal to the ADC clock;
an integer multiple of the ADC clock; or
a fraction of the ADC clock.
16. A method for operating an Analog to Digital Converter (ADC) comprising:
generating one or more voltages and one or more grounds using one or more switched capacitor voltage regulators that operate using a supply voltage, a supply ground, and an ADC clock;
sampling at least one incoming signal using a plurality of digital components that operate using the ADC clock, the one or more voltages, and the one or more grounds; and
operating on at least the incoming signal using a plurality of analog components that operate using the one or more voltages and the one or more grounds.
17. The method of claim 16 , wherein generating the one or more voltages and the one or more grounds using one or more switched capacitor voltage regulators further comprises operating the one or more switched capacitor voltage regulators using at least one of analog feedback and digital feedback.
18. The method of claim 16 , wherein:
the one or more of the voltages are generated at voltages greater than the supply voltage; and
the one or more of the grounds are generated at voltages less than the supply ground.
19. The method of claim 16 further comprising operating the switched capacitor voltage regulators using complementary and non-overlapping clocks that are based upon the ADC clock.
20. The method of claim 16 , wherein voltage levels of the one or more voltages and the one or more grounds are adapted based upon at least one of incoming signal amplitude, ADC clock frequency, process formation characteristics, supply voltage, supply ground, or operating temperature.