ANALOG-TO-DIGITAL CONVERTERS BASED ON AN INTERLEAVING ARCHITECTURE AND ASSOCIATED METHODS

• US 20070236380A1
• Filed: 04/06/2007
• Published: 10/11/2007
• Est. Priority Date: 04/07/2006
• Status: Active Grant

• Current Assignee: Washington State University
• Original Assignee: Washington State University
• Inventors: Guo, Haidong, La Rue, George
• Granted Patent: US 7,456,768 B2
• Time in Patent Office: Days
• US Class Current: 341/155
• CPC Class Codes: H03M 1/1215 using time-division multiplexing
• CPC Class Codes: H03M 1/1245 Details of sampling arrangements or methods
• CPC Class Codes: H03M 1/468 in which the input S/H circuit is merged with the feedback DAC array

Abstract

An analog-to-digital converter based on an interleaving architecture is disclosed. The analog-to-digital converter can include a first sample and hold circuit for sampling and temporarily storing a first input signal. The analog-to-digital converter can also include a comparator for converting the sampled first input signal into a digital signal in a first time period. The analog-to-digital converter can further include a second sample and hold circuit for sampling and temporarily storing a second input signal in a second time period. The second time period at least partially overlaps with the first time period.

Claims

1. An analog-to-digital converter, comprising:

a first sample and hold circuit for sampling and temporarily storing a first input signal;

a comparator for converting the sampled first input signal into a digital signal in a first time period; and

a second sample and hold circuit for sampling and temporarily storing a second input signal in a second time period, the second time period at least partially overlapping with the first time period.

2. The analog-to-digital converter of claim 1 wherein the first sample and hold circuit includes an array of capacitors having binary weighted capacitance.

3. The analog-to-digital converter of claim 1, further comprising:

a successive approximation register for initializing the digital signal; and

an internal digital-to-analog converter for generating a reference signal based on the initialized digital signal.

4. The analog-to-digital converter of claim 1 wherein the second sample and hold circuit sampling and temporarily storing a second input signal generally simultaneously as the comparator converts the sampled first input signal into a digital signal.

5. The analog-to-digital converter of claim 1, further comprising an input switch selectively connecting the first or second sample and hold circuit to the analog input and a comparator switch selectively connecting the first or second sample and hold circuit to the comparator.

6. The analog-to-digital converter of claim 1, further comprising a controller for switching the first or second sample and hold circuit to the analog input and/or to the comparator.

7. The analog-to-digital converter of claim 1 wherein the first sample and hold circuit includes a first array of capacitors, and wherein the second sample and hold circuit includes a second array of capacitors.

8. The analog-to-digital converter of claim 7 wherein individual first and second arrays of capacitors are selectively connectable to at least one of the first and second input signals.

9. The analog-to-digital converter of claim 7 wherein individual first and second arrays of capacitors include capacitors having capacitance of C, C/2, C/4, . . . , C/2^n-1, and C/2^n-1.

10. The analog-to-digital converter of claim 7 wherein a capacitor in the first array of capacitors has a capacitance that is generally the same as a corresponding capacitor in the second array of capacitors.

11. The analog-to-digital converter of claim 7 wherein individual first and second arrays of capacitors include a first and second rows of capacitors, capacitors in the first and second rows being generally identical.

12. An electronic device incorporating the analog-to-digital converter of claim 1.

13. An analog-to-digital converter, comprising:

first sampling means for sampling and temporarily storing a first input signal;

converting means for converting the sampled first input signal into a digital signal in a first time period; and

second sampling means for sampling and temporarily storing a second input signal in a second time period, the second time period at least partially overlapping with the first time period.

14. The analog-to-digital converter of claim 13, further comprising:

means for initializing the digital signal; and

means for generating a reference signal based on the initialized digital signal.

15. A method for converting an analog signal to a digital signal in an analog-to-digital converter, comprising:

sampling and temporarily storing a first input signal;

converting the sampled first input signal into a digital signal in a first time period; and

sampling and temporarily storing a second input signal in a second time period, the second time period at least partially overlapping with the first time period.

16. The method of claim 15 wherein sampling and temporarily storing a first input signal includes charging an array of capacitors having binary weighted capacitance.

17. The method of claim 15 wherein converting the sampled first input signal includes converting the sampled first input signal using successive approximation.

18. The method of claim 15, further comprising:

initializing the digital signal;

generating a reference signal based on the initialized digital signal; and

comparing the first input signal to the reference signal.

19. The method of claim 15 wherein sampling and temporarily storing a second input signal includes sampling and temporarily storing a second input signal generally simultaneously as converting the sampled first input signal into a digital signal.

20. The method of claim 15, further comprising converting the sampled second input signal into a digital signal while sampling and temporarily storing a third input signal.

21. The method of claim 15, further comprising reducing power consumption of the analog-to-digital converter by extending the first and/or the second time period near to the entire sample period.