System and method for analogtodigital converter with reduced average input current and reduced average reference current
System and method for analogtodigital converter with reduced average input current and reduced average reference current
 CN 101,044,682 B
 Filed: 10/17/2005
 Issued: 03/25/2015
 Est. Priority Date: 10/18/2004
 Status: Active Grant
First Claim
Patent Images
1. , to the method that differential analog input signal is sampled, described method comprises:
 Perform N number of sampling operation in succession to differential analog input signal, described N number of sampling operation in succession comprises;
With sampling apparatus, N is performed to differential analog input signal and the first reference signal _{0}individual sampling operation, N _{0}a subset of N number of sampling order, wherein at N _{0}the first stage of individual sampling operation, to a sampling in differential analog input signal and the first reference signal, at N _{0}the second stage of individual sampling operation, to another sampling in differential analog input signal and the first reference signal, With sampling apparatus, N is performed to differential analog input signal and the second reference signal _{1}individual sampling operation, N _{0}equal NN _{1}, wherein at N _{1}the first stage of individual sampling operation, to a sampling in differential analog input signal and the second reference signal, at N _{1}the second stage of individual sampling operation, to another sampling in differential analog input signal and the second reference signal, performs N _{1}individual sampling operation and execution N _{0}individual sampling operation universally from providing the differential analog input signal source of differential analog input signal to extract the average differential current be substantially zero, Wherein said differential analog input signal comprises the amplitude V being more than or equal to the first reference signal _{l}, and be less than or equal to the amplitude V of the second reference signal _{h}amplitude V _{i}, wherein the amplitude of the second reference signal is greater than the amplitude of the first reference signal, and wherein N _{1}=N* (V _{i}V _{l})/(V _{h}V _{l}).
Chinese PRB Reexamination
Abstract
A novel sampling system having a sampling device responsive to an analog input signal and a reference signal for providing corresponding charges. A switching circuit is provided to supply the input signal and the reference signal to the sampling device. The switching circuit is controlled to supply the input signal and the reference signal to the sampling device so as provide a substantially zero total charge taken by the sampling device from a source of the input signal. One application of the foregoing is in analogtodigital conversion.
32 Claims

1. , to the method that differential analog input signal is sampled, described method comprises:

Perform N number of sampling operation in succession to differential analog input signal, described N number of sampling operation in succession comprises; With sampling apparatus, N is performed to differential analog input signal and the first reference signal _{0}individual sampling operation, N _{0}a subset of N number of sampling order, wherein at N _{0}the first stage of individual sampling operation, to a sampling in differential analog input signal and the first reference signal, at N _{0}the second stage of individual sampling operation, to another sampling in differential analog input signal and the first reference signal, With sampling apparatus, N is performed to differential analog input signal and the second reference signal _{1}individual sampling operation, N _{0}equal NN _{1}, wherein at N _{1}the first stage of individual sampling operation, to a sampling in differential analog input signal and the second reference signal, at N _{1}the second stage of individual sampling operation, to another sampling in differential analog input signal and the second reference signal, performs N _{1}individual sampling operation and execution N _{0}individual sampling operation universally from providing the differential analog input signal source of differential analog input signal to extract the average differential current be substantially zero, Wherein said differential analog input signal comprises the amplitude V being more than or equal to the first reference signal _{l}, and be less than or equal to the amplitude V of the second reference signal _{h}amplitude V _{i}, wherein the amplitude of the second reference signal is greater than the amplitude of the first reference signal, and wherein N _{1}=N* (V _{i}V _{l})/(V _{h}V _{l}).


2. the method for claim 1, described method also comprises and utilizes onoff controller, produces one group of specific sampling order according to differential analog input signal and the numeral of the ratio of the first and second reference signals.

3. the method for claim 1, described method also comprises response sample operation and differential analog input signal is transformed into data signal.

4. the method for claim 3, described method also comprises and utilizes delta sigma modulator as sampling apparatus, described delta sigma modulator comprises:
 connect into the sampling capacitor performing sampling operation, connect into the integrating condenser receiving sampled signal from sampling capacitor, be connected to the voltage amplifier on described integrating condenser, be applicable to the comparator of the output of receiver voltage amplifier, and the analog switch of the operation of multiple adjustment delta sigma modulator.

5. the method for claim 4, wherein said sampling capacitor is multiple sampling capacitors.

6. the method for claim 4, wherein said integrating condenser is multiple integrating condensers.

7. the method for claim 2, described method also comprises with delta sigma modulator as sampling apparatus, and the output stream of described delta sigma modulator comprises the information relevant relative to the relative magnitude of the first and second reference signals respectively with differential analog input signal that data signal draws with the output stream from delta sigma modulator.

8. the method for claim 3, wherein said data signal forms multiple bit digital signal.

9. utilizing delta sigma modulator differential analog input signal to be transformed into data signal makes described conversion extract a method for the average differential current be substantially zero from differential analog input signal source, and described differential analog input signal comprises the amplitude V being more than or equal to the first reference signal _{l}, and be less than or equal to the amplitude V of the second reference signal _{h}amplitude V _{i}, wherein the amplitude of the second reference signal is greater than the amplitude of the first reference signal, and described method comprises:

Obtain the binary system corresponding to data signal from delta sigma modulator to export; If it is the first output 0 that described binary system exports, then Perform N _{0}individual sampling operation to sample in differential analog input signal and the first reference signal, N _{0}a subset of N number of sampling order, and Then another in differential analog input signal and the first reference signal is sampled;
AndIf it is the second output 1 that described binary system exports, then Perform N _{1}individual sampling operation to sample in differential analog input signal and the second reference signal, wherein N _{0}=NN _{1}, and Then another in differential analog input signal and the second reference signal is sampled, wherein N _{1}=N* (V _{i}V _{l})/(V _{h}V _{l}).


10. the method for claim 9, wherein obtain binary system to export and also comprise one of the following binary system that obtains of response and export:
 (1) is to the sampling of differential analog input signal and the sampling to the first reference signal, and (2) are to the sampling of differential analog input signal and the sampling to the second reference signal.

11. 1 kinds of methods differential analog input signal being transformed into highaccuracy digital signal, described method comprises:

With low precision AD converter to differential analog input signal, the first reference signal and the second reference signal samples, to provide low accuracy digital signal, described differential analog input signal comprises the amplitude V being more than or equal to the first reference signal _{l}, and be less than or equal to the amplitude V of the second reference signal _{h}amplitude V _{i}, wherein the amplitude of the second reference signal is greater than the amplitude of the first reference signal;
Low accuracy digital signal is used to realize switching sequence in highaccuracy AD converter, this switching sequence control differential analog input signal sampling and with the analog to digital conversion of highaccuracy AD converter to differential analog input signal, to produce highaccuracy digital signal, the average differential current be substantially zero is extracted in the sampling of described highaccuracy AD converter from differential analog input signal source, wherein the sampling of highaccuracy AD converter comprises differential analog input signal and the first reference signal execution N _{0}individual sampling operation, N _{0}a subset of N number of sampling order, wherein at N _{0}the first stage of individual sampling operation, to a sampling in differential analog input signal and the first reference signal, at N _{0}the second stage of individual sampling operation, to another sampling in differential analog input signal and the first reference signal, and performs N to differential analog input signal and the second reference signal _{1}individual sampling operation, wherein N _{0}=NN _{1}, wherein at N _{1}the first stage of individual sampling operation, to a sampling in differential analog input signal and the second reference signal, at N _{1}the second stage of individual sampling operation, to another sampling in differential analog input signal and the second reference signal, wherein N _{1}=N* (V _{i}V _{l})/(V _{h}V _{l}).


12.
The method of 12. claims 11, described method also comprises with delta sigma modulator as low precision AD converter, described delta sigma modulator comprises:  connect into the sampling capacitor performing sampling operation, connect into the integrating condenser receiving sampled signal from sampling capacitor, be connected to the voltage amplifier on described integrating condenser, be applicable to the comparator of the output of receiver voltage amplifier, and the analog switch of the operation of multiple adjustment delta sigma modulator.

13.
The method of 13. claims 12, wherein said sampling capacitor is multiple sampling capacitors.

14.
The method of 14. claims 12, wherein said integrating condenser is multiple integrating condensers.

15.
The method of 15. claims 11, also comprise with delta sigma modulator as highaccuracy AD converter, described delta sigma modulator comprises:  connect into the sampling capacitor performing sampling operation, connect into the integrating condenser receiving sampled signal from sampling capacitor, be connected to the voltage amplifier on described integrating condenser, be applicable to the comparator of the output of receiver voltage amplifier, and the analog switch of the operation of multiple adjustment delta sigma modulator.

16.
The method of 16. claims 15, wherein said sampling capacitor is multiple sampling capacitors.

17.
The method of 17. claims 15, wherein said integrating condenser is multiple integrating condensers.

18.
The method of 18. claims 11, described method also comprise utilize highaccuracy digital signal formed multiple bit digital signal.

19. 1 kinds of AD converters differential analog input signal being transformed into highaccuracy digital signal, described AD converter comprises:

First reference signal input, for receiving the first reference signal; Second reference signal input, for receiving the second reference signal; Described differential analog input signal has the amplitude V being more than or equal to the first reference signal _{l}, and be less than or equal to the amplitude V of the second reference signal _{h}amplitude V _{i}, wherein the amplitude of the second reference signal is greater than the amplitude of the first reference signal;
Differential analog input signal, the first reference signal and the second reference signal are sampled and samples according to these and low precision AD converter of low accuracy digital signal is provided; The highaccuracy AD converter controlled by the switching sequence based on low accuracy digital signal, described switching sequence controls highaccuracy AD converter to the sampling of differential analog input signal, the first reference signal and the second reference signal, and control the analog to digital conversion of highaccuracy AD converter to differential analog input signal, to produce highaccuracy digital signal, wherein the sampling of highaccuracy AD converter comprises differential analog input signal and the first reference signal execution N _{0}individual sampling operation, N _{0}a subset of N number of sampling order, wherein at N _{0}the first stage of individual sampling operation, to a sampling in differential analog input signal and the first reference signal, at N _{0}the second stage of individual sampling operation, to another sampling in differential analog input signal and the first reference signal, and performs N to differential analog input signal and the second reference signal _{1}individual sampling operation, wherein N _{0}=NN _{1}, wherein at N _{1}the first stage of individual sampling operation, to a sampling in differential analog input signal and the second reference signal, at N _{1}the second stage of individual sampling operation, to another sampling in differential analog input signal and the second reference signal, wherein N _{1}=N* (V _{i}V _{l})/(V _{h}V _{l}).


20.
The converter of 20. claims 19, wherein said low precision AD converter comprises delta sigma modulator, and described delta sigma modulator comprises: 
Sampling capacitor; The integrating condenser of sampled signal is received from sampling capacitor; Be connected to the voltage amplifier on integrating condenser; Be applicable to the comparator of the output of receiver voltage amplifier;
AndThe analog switch of the operation of multiple adjustment delta sigma modulator.


21.
The converter of 21. claims 20, wherein said sampling capacitor is multiple sampling capacitors.

22.
The converter of 22. claims 20, wherein said integrating condenser is multiple integrating condensers.

23.
The converter of 23. claims 19, wherein said highaccuracy AD converter comprises delta sigma modulator, and described delta sigma modulator comprises: 
Sampling capacitor; The integrating condenser of sampled signal is received from sampling capacitor; Be connected to the voltage amplifier on integrating condenser; Be applicable to the comparator of the output of receiver voltage amplifier;
AndThe analog switch of the operation of multiple adjustment delta sigma modulator.


24.
The converter of 24. claims 23, wherein said sampling capacitor is multiple sampling capacitors.

25.
The converter of 25. claims 23, wherein said integrating condenser is multiple integrating condensers.

26.
The converter of 26. claims 19, also comprises the onoff controller realizing switching sequence.

27.
The converter of 27. claims 19, wherein said highaccuracy digital signal comprises multiple bit digital signal.

28.
The converter of 28. claims 19, wherein said highaccuracy AD converter extracts the average differential current be substantially zero from differential analog input signal source.

29.
The converter of 29. claims 19, wherein said highaccuracy AD converter extracts from providing the differential analog input source of differential analog input signal the average current be substantially zero to the sampling of differential analog input signal, the first reference signal and the second reference signal.

30.
The converter of 30. claims 19, wherein said highaccuracy AD converter also comprises delta sigma modulator, and described delta sigma modulator comprises: 
To the sampling capacitor of analog input signal sampling; The integrating condenser of sampled signal is received from sampling capacitor; Be connected to the voltage amplifier on integrating condenser; Be applicable to the comparator of the output of receiver voltage amplifier;
AndMultiple basis adjusts the analog switch of the operation of delta sigma modulator from the switching drive signal that the onoff controller be connected with the output of comparator receives.


31. 1 kinds of AD converters differential analog input signal being transformed into data signal, described AD converter comprises:

Be applied to the delta sigma modulator of differential analog input signal input, described input is for receiving described differential analog input signal;
AndMultiple reference signal input, for receiving multiple reference signal, described multiple reference signal comprises the first reference signal and the second reference signal; Output, exports for the binary system exporting AD converter; Described delta sigma modulator is used as sample circuit; If wherein described binary system exports is the first output 0, then Sample circuit performs N _{0}individual sampling operation to sample in differential analog input signal and the first reference signal, N _{0}a subset of N number of sampling order, described differential analog input signal V _{i}be more than or equal to the first reference signal V _{l}, and Then described sample circuit is sampled to another in differential analog input signal and the first reference signal;
AndIf it is the second output 1 that described binary system exports, then Sample circuit performs N _{1}individual sampling operation to sample in differential analog input signal and the second reference signal, wherein N _{0}=NN _{1}, described differential analog input signal V _{i}be less than or equal to the second reference signal V _{h}, and Then described sample circuit is sampled to another in differential analog input signal and the second reference signal, and Wherein the amplitude of the second reference signal is greater than the amplitude of the first reference signal, wherein N _{1}=N* (V _{i}V _{l})/(V _{h}V _{l}).


32.
The converter of 32. claims 31, wherein also comprise one of the following binary system that obtains of response to export:  (1) is to the sampling of differential analog input signal and the sampling to the first reference signal, and (2) are to the sampling of differential analog input signal and the sampling to the second reference signal.
Specification(s)