CN110166010A - A kind of scaling circuit can be used for expanding capacitive digital converter range and method - Google Patents
A kind of scaling circuit can be used for expanding capacitive digital converter range and method Download PDFInfo
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- CN110166010A CN110166010A CN201910527514.5A CN201910527514A CN110166010A CN 110166010 A CN110166010 A CN 110166010A CN 201910527514 A CN201910527514 A CN 201910527514A CN 110166010 A CN110166010 A CN 110166010A
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- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
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Abstract
The present invention relates to a kind of scaling circuit that can be used for expanding capacitive digital converter range and methods, including the first phase inverter, the second phase inverter, integrating phase switch, sample phase switches, amplifier, resistance R1, capacitor eliminate matrix module and capacitor scales resistor matrix module；Capacitance is carried out to the capacitor to be read using capacitor scaling resistor matrix module integrally to reduce, matrix module is then eliminated using capacitor and eliminates starting capacitor, will be measured in the capacitor input capacitance digital quantizer CDC circuit obtained by previous processed.The present invention is able to solve aiming at the problem that CDC chip general when big capacitance is converted into respective digital amount can not be read due to lesser capacitor input range.
Description
Technical field
The present invention relates to sensor technical field, especially a kind of scaling that can be used for expanding capacitive digital converter range
Circuit and method.
Background technique
Due to the rapid development of Internet of Things and artificial intelligence technology, various forms of sensors have become the world today can not
Or scarce important component.Capacitance sensor is a kind of sensor of most important one, can be used for measuring displacement, angle change
With the variation of dielectric layer.For these physical quantitys to be measured, capacitance sensor is translated into the variation of capacitance.
Capacitive digital converter (Capacitance-to-Digital Converter, behind abbreviation CDC) chip is normal
Capacitance can be converted to digital form output by the readout chip seen.For the world today, increasingly digitize and integrated
For the electronic product of change, capacitive digital converter chip is to realize that physical quantity of concern is converted to digital quantity for micro- place by it
Manage an important ring for device processing.However, the capacitance that common CDC chip can be read is very small.Such as 2017, Hesham
Omran et al. be published in " IEEE Transactions on Circuits and System I " one introduces its design
There was only 0-12.66pF with the CDC input capacitance range that SAR form is realized.It is published within Christopher Rogi et al. 2018
A paper of ESSCIRC illustrates that a CDC chip of its design, input range only have 0.27-0.9pF.For in the market
Common capacitance sensor, capacitance range move pF then up to a hundred, directly can not carry out reading using these CDC chips at all and turn
It changes.Such as with common relative humidity sensor HS1101 currently on the market for, this sensor is by the variable quantity of relative humidity
It is converted into the variation of capacitance.Shown in its capacitor and the response relation of relative humidity such as formula (1):
C (pF)=180 (1.2510-7RH3-1.36·10-5·RH2+2.19·10-3RH+0.9) (1)
Under 25 DEG C of environment temperature, when relative humidity variations range is 0%-100%, capacitance variation amount is
162pF-199.44pF.Either input capacitance dynamic range or its start to walk capacitance all considerably beyond it is most
The document or commercial product CDC delivered input range (starting capacitor refer to that the sensor is unrelated with relative humidity in the case where,
Its position of minimum capacitance, dynamic capacity refer to the sensor in the capacitance of relative humidity variations range).
Summary of the invention
In view of this, the purpose of the present invention is to propose to a kind of scaling circuits that can be used for expanding capacitive digital converter range
And method, general CDC chip is able to solve when being converted into respective digital amount for big capacitance due to lesser electricity
Hold the problem of input range can not be read.
The present invention is realized using following scheme: a kind of scaling circuit can be used for expanding capacitive digital converter range, packet
It includes the first phase inverter, the second phase inverter, integrating phase switch, sample phase switches, amplifier, resistance R1, capacitor and eliminates matrix norm
Block and capacitor scale resistor matrix module；
One end of first phase inverter is connected to one end of integrating phase switch, the other end of the integrating phase switch
It is respectively connected to one end of sample phase switches, one end of capacitor elimination matrix module, the other end of the sample phase switches
It is respectively connected to the output end and negative input end of amplifier, the capacitor eliminates another termination virtual earth of matrix module；The amplifier
Positive input terminal be separately connected one end of resistance R1, capacitor scaling resistor matrix module one end, the other end of the resistance R1
It is connected to one end of the second phase inverter, the other end of second phase inverter is separately connected the other end of the first phase inverter, capacitor
Scale the other end of resistor matrix module；
Wherein, the other end of sample phase switches and capacitor eliminate input of the other end of matrix module as scaling circuit
End, to access testing capacitance Csensor；Output end of the other end of second phase inverter as scaling circuit, to connect
CDC circuit.
Further, it includes first capacitor control switch S1, the second capacitance controlled switches that the capacitor, which eliminates matrix module,
S2, third capacitance controlled switches S3, the 4th capacitance controlled switches S4, first capacitor C1, the second capacitor C2, third capacitor C3, with
And the 4th capacitor C4；One end of the first capacitor control switch S1, one end of the second capacitance controlled switches S2, third capacitor control
One end of one end and the 4th capacitance controlled switches S4 for making switch S3 is connected and eliminates the one of matrix module as the capacitor
End；The other end, the third capacitance controlled switches of the other end of the first capacitor control switch S1, the second capacitance controlled switches S2
The other end of the other end of S3 and the 4th capacitance controlled switches S4 respectively with one end of the first capacitor C1, the second capacitor C2
One end, third capacitor C3 one end and the 4th capacitor C4 one end be connected, the other end of the first capacitor C1, second electricity
The other end for holding the other end of C2, the other end of third capacitor C3 and the 4th capacitor C4 is connected and eliminates square as the capacitor
The other end of battle array.
Preferably, the implementation of the capacitor Zoom module includes three kinds.
The first are as follows: the capacitor scaling resistor matrix module includes the first scaling resistance control switch Sw1, the second scaling
Resistance control switch Sw2, third scaling resistance control switch Sw3, the 4th scaling resistance control switch Sw4, the first scaling resistance
Rx1, the second scaling resistance Rx2, the third scaling of scaling resistance Rx3 and the 4th resistance Rx4；The first scaling resistance Rx1's
One end that one end, one end of the second scaling resistance Rx2, one end of third scaling resistance Rx3 and the 4th scale resistance Rx4 is connected
And one end as capacitor scaling resistor matrix module；The other end, the second scaling resistance of the first scaling resistance Rx1
The other end of the other end of Rx2, the other end of third scaling resistance Rx3 and the 4th scaling resistance Rx4 is scaled with first respectively
One end of resistance control switch Sw1, one end of the second scaling resistance control switch Sw2, third scale resistance control switch Sw3's
One end and one end of the 4th scaling resistance control switch Sw4 are connected；The first scaling resistance control switch Sw1's is another
End, the other end of the second scaling resistance control switch Sw2, the other end of third scaling resistance control switch Sw3 and the 4th contracting
The other end of electric discharge resistance control switch Sw4 is connected and the other end as capacitor scaling resistor matrix module.
When in this way, first phase inverter, the second phase inverter, integrating phase switch, sample phase switches,
Amplifier, resistance R1, capacitor are eliminated matrix module, capacitor scaling resistor matrix module and CDC circuit and are integrated in piece.
Second are as follows: on the basis of the first, the capacitor scaling resistor matrix module further includes slide rheostat Rx
Interface and slide rheostat access switch Sw interface, access switch Sw to external slide rheostat Rx and slide rheostat；Its
Middle slide rheostat Rx interface is attempted by the capacitor scaling resistor matrix after concatenating with slide rheostat access switch Sw interface
The both ends of module.
When in this way, first phase inverter, the second phase inverter, integrating phase switch, sample phase switches,
Amplifier, resistance R1, capacitor eliminate matrix module and CDC circuit is integrated in piece, and the capacitor scales resistor matrix module
In slide rheostat Rx interface and slide rheostat access switch Sw interface be arranged outside piece, capacitor scaling resistor matrix module
In remaining component be integrated in piece.In practical applications, can according to need choose whether slide rheostat to be accessed with
Slide rheostat access switch.
The third are as follows: the capacitor scaling resistor matrix module includes that slide rheostat Rx and slide rheostat access switch
One end of Sw, the slide rheostat Rx are connected with one end of slide rheostat access switch Sw, the slide rheostat
The one end of the other end of Rx as capacitor scaling resistor matrix module, the other end of the slide rheostat access switch Sw
The other end as capacitor scaling resistor matrix module.
When in this way, first phase inverter, the second phase inverter, integrating phase switch, sample phase switches,
Amplifier, resistance R1, capacitor eliminate matrix module and CDC circuit is integrated in piece, and the capacitor scales resistor matrix module
It is arranged outside piece.
The present invention also provides a kind of based on the scaling electricity that can be used for expanding capacitive digital converter range described above
The method on road, specifically: capacitance is carried out to the capacitor to be read using capacitor scaling resistor matrix module and is integrally reduced, then
Matrix module is eliminated using capacitor and eliminates starting capacitor, the capacitor input capacitance digital quantizer that will be obtained by previous processed
It is measured in CDC circuit.
Compared with prior art, the invention has the following beneficial effects: the present invention can effectively realize bulky capacitor measurement, adapt to
At this stage due to the development of technology of Internet of things, bulky capacitor sensor capacitance value reads, can neatly be counted with microprocessor
According to interaction.
Detailed description of the invention
Fig. 1 is that the integral capacitor of the embodiment of the present invention scales schematic illustration.
Fig. 2 is that the starting capacitor of the embodiment of the present invention eliminates schematic illustration.
Fig. 3 is that adjustable resistance R2 schematic diagram is realized outside the piece of the embodiment of the present invention.
When Fig. 4 is that the adjustable resistance form of the embodiment of the present invention realizes R2, the variation range of β.
Fig. 5 is that the resistor matrix form of the embodiment of the present invention realizes R2 circuit diagram.
Fig. 6 is that being realized in the form of capacitance matrix for the embodiment of the present invention selects starting capacitor elimination value.
Fig. 7 is a kind of Telescopic amplifier way of realization of the embodiment of the present invention.
Fig. 8 is a kind of PMOS input form folded cascode Op Amp way of realization of the embodiment of the present invention.
Fig. 9 is a kind of way of realization that can be used for amplifier in Fig. 1 of the embodiment of the present invention.
Figure 10 is that the circuit of the embodiment of the present invention realizes schematic diagram.Wherein off chip resistor Rw (i.e. R2) is alternative and connects.
Specific embodiment
The present invention will be further described with reference to the accompanying drawings and embodiments.
It is noted that described further below be all exemplary, it is intended to provide further instruction to the application.Unless another
It indicates, all technical and scientific terms used herein has usual with the application person of an ordinary skill in the technical field
The identical meanings of understanding.
It should be noted that term used herein above is merely to describe specific embodiment, and be not intended to restricted root
According to the illustrative embodiments of the application.As used herein, unless the context clearly indicates otherwise, otherwise singular
Also it is intended to include plural form, additionally, it should be understood that, when in the present specification using term "comprising" and/or " packet
Include " when, indicate existing characteristics, step, operation, device, component and/or their combination.
As shown in Figure 10, a kind of scaling circuit that can be used for expanding capacitive digital converter range is present embodiments provided,
Matrix is eliminated including the first phase inverter, the second phase inverter, integrating phase switch, sample phase switches, amplifier, resistance R1, capacitor
Module and capacitor scale resistor matrix module；
One end of first phase inverter is connected to one end of integrating phase switch, the other end of the integrating phase switch
It is respectively connected to one end of sample phase switches, one end of capacitor elimination matrix module, the other end of the sample phase switches
It is respectively connected to the output end and negative input end of amplifier, the capacitor eliminates another termination virtual earth of matrix module；The amplifier
Positive input terminal be separately connected one end of resistance R1, capacitor scaling resistor matrix module one end, the other end of the resistance R1
It is connected to one end of the second phase inverter, the other end of second phase inverter is separately connected the other end of the first phase inverter, capacitor
Scale the other end of resistor matrix module；
Wherein, the other end of sample phase switches and capacitor eliminate input of the other end of matrix module as scaling circuit
End, to access testing capacitance Csensor；Output end of the other end of second phase inverter as scaling circuit, to connect
CDC circuit.
In the present embodiment, it includes first capacitor control switch S1, the second Capacity control that the capacitor, which eliminates matrix module,
Switch S2, third capacitance controlled switches S3, the 4th capacitance controlled switches S4, first capacitor C1, the second capacitor C2, third capacitor
C3 and the 4th capacitor C4；One end, one end of the second capacitance controlled switches S2, third of the first capacitor control switch S1
One end of capacitance controlled switches S3 and one end of the 4th capacitance controlled switches S4 are connected and eliminate matrix norm as the capacitor
One end of block；The other end of the first capacitor control switch S1, the other end of the second capacitance controlled switches S2, third capacitor control
Make switch S3 the other end and the 4th capacitance controlled switches S4 the other end respectively with one end of the first capacitor C1, second
One end of one end of capacitor C2, one end of third capacitor C3 and the 4th capacitor C4 is connected, the other end of the first capacitor C1,
The other end of the other end of second capacitor C2, the other end of third capacitor C3 and the 4th capacitor C4 is connected and as the capacitor
Eliminate the other end of matrix.
Preferably, in the present embodiment, the implementation of the capacitor Zoom module includes three kinds.
The first are as follows: the capacitor scaling resistor matrix module includes the first scaling resistance control switch Sw1, the second scaling
Resistance control switch Sw2, third scaling resistance control switch Sw3, the 4th scaling resistance control switch Sw4, the first scaling resistance
Rx1, the second scaling resistance Rx2, the third scaling of scaling resistance Rx3 and the 4th resistance Rx4；The first scaling resistance Rx1's
One end that one end, one end of the second scaling resistance Rx2, one end of third scaling resistance Rx3 and the 4th scale resistance Rx4 is connected
And one end as capacitor scaling resistor matrix module；The other end, the second scaling resistance of the first scaling resistance Rx1
The other end of the other end of Rx2, the other end of third scaling resistance Rx3 and the 4th scaling resistance Rx4 is scaled with first respectively
One end of resistance control switch Sw1, one end of the second scaling resistance control switch Sw2, third scale resistance control switch Sw3's
One end and one end of the 4th scaling resistance control switch Sw4 are connected；The first scaling resistance control switch Sw1's is another
End, the other end of the second scaling resistance control switch Sw2, the other end of third scaling resistance control switch Sw3 and the 4th contracting
The other end of electric discharge resistance control switch Sw4 is connected and the other end as capacitor scaling resistor matrix module.
When in this way, first phase inverter, the second phase inverter, integrating phase switch, sample phase switches,
Amplifier, resistance R1, capacitor are eliminated matrix module, capacitor scaling resistor matrix module and CDC circuit and are integrated in piece.
Second are as follows: on the basis of the first, the capacitor scaling resistor matrix module further includes slide rheostat Rx
Interface and slide rheostat access switch Sw interface, access switch Sw to external slide rheostat Rx and slide rheostat；Its
Middle slide rheostat Rx interface is attempted by the capacitor scaling resistor matrix after concatenating with slide rheostat access switch Sw interface
The both ends of module.
When in this way, first phase inverter, the second phase inverter, integrating phase switch, sample phase switches,
Amplifier, resistance R1, capacitor eliminate matrix module and CDC circuit is integrated in piece, and the capacitor scales resistor matrix module
In slide rheostat Rx interface and slide rheostat access switch Sw interface be arranged outside piece, capacitor scaling resistor matrix module
In remaining component be integrated in piece.In practical applications, can according to need choose whether slide rheostat to be accessed with
Slide rheostat access switch.
The third are as follows: the capacitor scaling resistor matrix module includes that slide rheostat Rx and slide rheostat access switch
One end of Sw, the slide rheostat Rx are connected with one end of slide rheostat access switch Sw, the slide rheostat
The one end of the other end of Rx as capacitor scaling resistor matrix module, the other end of the slide rheostat access switch Sw
The other end as capacitor scaling resistor matrix module.
When in this way, first phase inverter, the second phase inverter, integrating phase switch, sample phase switches,
Amplifier, resistance R1, capacitor eliminate matrix module and CDC circuit is integrated in piece, and the capacitor scales resistor matrix module
It is arranged outside piece.
The present embodiment additionally provides a kind of based on the scaling that can be used for expanding capacitive digital converter range described above
The method of circuit, specifically: capacitance is carried out to the capacitor to be read using capacitor scaling resistor matrix module and is integrally reduced, is connect
Matrix module eliminated using capacitor eliminate starting capacitor, the capacitor input capacitance digital quantizer that will be obtained by previous processed
It is measured in CDC circuit.
Next combine Figure of description that the principle of the present invention is specifically described.
Covert zoom technology is divided into two processes.The present embodiment for reading HS1101 relative humidity sensor capacitor,
In the case of 25 DEG C, in its relative humidity working range, starting capacitor is 162pF, dynamic capacity 37.44pF.
The first job process of covert zoom technology is to carry out capacitance to the capacitor to be read integrally to reduce.
Specific circuitous pattern is as shown in Figure 1.Assuming that capacitor to be measured is Csensor, empty short and empty first with amplifier
Disconnected property obtains formula (2):
Notice VAAnd VBIt is that amplitude is equal, therefore two driving voltages of opposite in phase can make into one formula (2)
The simplification of step obtains formula (3):
Definition β is voltage amplification factor, while being also capacitor zoom factor.
It notices and is applied to C in two above-mentioned reverse phase driving voltagessensorCharge and discharge really are carried out to it in the process
Process, therefore, Yao Zunshou principle of charge conservation.Formula (4) can be obtained using the principle:
For subsequent circuit, the capacitance which actually " can see " subsequent conditioning circuit will become
Formula (5), equivalent capacitance value is denoted as Cx.Then, which completes the capacitor integral value to be completed of covert zoom technology
Reduce β times of purpose, including starting capacitor and dynamic capacity.
What second course of work of covert zoom technology to be completed is to eliminate starting capacitor.It can be seen that for
For HS1101, in its relative humidity variations range, the capacitance that starts to walk is not changed, and therefore, subsequent CDC circuit is come
It says, which is a unfavorable factor, it is necessary to for further processing.
The present embodiment devises a kind of capacitor elimination circuit, can eliminate capacitance to a certain extent.
As shown in Fig. 2, the voltage of opposite in phase equal using two amplitudes, in the integral phase of CDC work to surveying
The capacitance of amount charges.In sampling phase, by capacitor CxAnd CoffIt is coupled to the input terminal of CDC, utilizes charge conservation
Principle will obtain formula (6).For the CDC for using sigma delta type modulator, CDC is the tune of a charge balance
Process processed, the input quantity being primarily upon are the quantities of electric charge by being converted after charging by capacitor.
Qeq=VchargeCx-VchargeCoff (6)
Therefore, the final equivalent capacitance value C after completing covert zoom technologyeqIt will be provided by formula (7).
CeqIt is exactly the capacitance value range of its measurement for subsequent capacitance digital quantizer.It is proposed by the present invention covert
Zoom technology is suitable for the CDC of charge balance form.
In actual mechanical process, a capacitance range to be measured may not be fixation, therefore, in a disguised form scaling
Certain coefficient adjustment is needed for technology to adapt to new range to be measured.As shown in formula (8), adjustable scaling
There are two coefficients, and one is capacitor zoom factor β, the other is starting capacitance Coff。
The present embodiment separately designs the sub-circuit of adjusting parameter for the two coefficients.
For β, as shown in formula (3), value can be by adjusting R1And R2Resistance value is changed.To formula
(3) suitably changed available formula (9).It is the ratio of two resistance wherein shown in the definition of η such as formula (10).
It can be by R for simplification1Value fix, only change R2.By R when a kind of method is actual chips design1Design is in chip
It is interior, flow encapsulation is participated in, and by R2It is reserved with the interface of entire covert zoom technology, by connecing an adjustable resistance outside chip
To realize the variation of β.So such variation range will be traversal R2Entire constant interval, the most flexibly.Specific connection such as Fig. 3 institute
Show, R2It is realized outside piece, covert zoom technology remaining circuit and CDC circuit are all realized in piece.Wherein CDC circuit can use science
The general CDC circuit in boundary and market.But due to R2It is to be realized outside piece, disadvantage is it is also obvious that be just reduction of integrated
Degree.Such as with R1It is designed as 47k Ω, R2It is designed as adjustable resistance, if by R2Adjust the variation in 47.47k Ω -51.7k Ω
Range, then β (Beta) will flexibly change in the section of 21-201, as shown in Figure 4.
Another method is R1And R2It is all realized in piece, wherein R1It is fixed, R2By designing one group of resistance in the chip
Matrix is realized, internal R is determined by external toggle switch2Specific value.By R2It is realized in the form of resistor matrix, such as Fig. 5 institute
Show, passes through four toggle switch Sw1-Sw4, determine the resistance value of access.In R1It, can be by R in the case where for 47k Ωw1, Rw2, Rw3With
Rw4Separately design as 57.44k Ω, 51.95k Ω, 48.92k Ω, 47.95k Ω realize it is corresponding set 10 times for β value, 20 times,
50 times and 100 times.Above-mentioned resistance value can be realized by poly resistance form on chip, because poly resistance is guaranteeing resistance
It is worth relatively accurate while higher resistance value is provided.Only drawback is that η variable range is fixed several values.
Start to walk capacitor elimination value CoffSpecific value can be selected by toggle switch by chip designs capacitance matrix
It is configured.As shown in fig. 6, passing through four capacitor C1, C2, C3And C4, its value is set to 0.1pF respectively, 0.2pF, 0.4pF and
0.8pF passes through external toggle switch S1-S4It is configured and which capacitor access is determined.Therefore CoffVariation range will become
For 0-1.5pF, stepping 0.1pF.
Due to being needed in Fig. 1 using to amplifier, it is therefore necessary to design amplifier particular circuit configurations.
A kind of amplifier structure realizes biggish gain as shown in fig. 7, by by Telescopic form.But due to
The presence of bottom M9 pipe, output end DC potential are generally notIn addition, its input terminal is M7, two NMOS of M8
Pipe is constituted, and therefore, when common mode input is close to 0V, amplifier cannot normally amplify.Another amplifier structure such as Fig. 8 institute
Show, be a kind of Foldable cascade structure that PMOS tube work inputs, although there is no output common mode voltage is inclined for the type amplifier
The case where shifting, but its common mode input when close to VDD, therefore PMOS tube will be also not suitable in linear zone or cut-off region
Amplifier in Fig. 1.It similarly, will be since common mode input be close to 0V as the Foldable cascade of input pipe using NMOS
When, input is in linear zone or cut-off region to pipe and is not suitable for the amplifier in Fig. 1.
Present embodiments provide a kind of amplifier structure that can be used in Fig. 1 as shown in figure 9, input common source voltage from 0V to
When VDD changes, input works to Guan Junke, and wherein the breadth length ratio of M2 and M3 will be arranged to the relationship of 3:1, the width of M10 and M11
The long relationship than to be arranged to 1:3.
Preferably, amplifier shown in Fig. 9 is not the structure that amplifier is best in realization Fig. 1.If using Ron
A paper " the Acompact power-efficient 3V CMOS that Hogervorst is published on JSSC for 1994
Rail-to-rail input/output operational amplifierforVLSI cell libraries " in illustrate
The rail-to-rail amplifier structure of low pressure, better effect will be formed.This is because the amplifier in Fig. 1 is mainly with Unity-gain buffer
The form of device occurs, and output connects into negative-feedback with input.Therefore, it is larger that the DC potential inputted will follow output to occur
The amplitude of oscillation variation.If realizing amplifier in the form of rail-to-rail input, the short-circuit mutual conductance of amplifier will not change with input, i.e.,
It realizes that mutual conductance is constant, so that the DC current gain for reaching amplifier is constant, realizes better effect.
Particularly, Figure 10 gives the present embodiment and is implemented in combination with covert zoom technology and CDC in piece and outside piece in conjunction with whole
Body circuit diagram.Wherein phase1 and phase2 is the integral phase in existing academia and common commercial product in discrete type ADC timing
Bit switch and sample phase switches.CDC circuit can be real using common Sigma Delta type CDC in academia or other forms
It is existing, due to being an interface circuit of the present embodiment, repeat no more.Except RxAnd SwOutside, remaining can be realized in piece, cocurrent
Piece is packaged so as to integrated.RxAnd SwPiece external tapping can be stayed, specifically whether is connect, depending on actual needs, does not influence to integrate
Degree.CoffThe switch S of capacitance matrix1-S4(switch in the form of transmission gate realize) can by the form control transmission gate of register into
Row is realized, similarly, in R2 resistor matrix, controls Rx1-Rx4Switch Sw1-Sw4Transmission gate can also be controlled by register to carry out in fact
It is existing.
In addition, the expanded range range of the present embodiment introduction can be controlled by capacitance matrix and resistor matrix, it can
Adapt to the reading of the capacitance sensor or capacitor of different range abilities.Its capacitance matrix and resistor matrix control switch can be in pieces
It is interior to be realized in the form of toggle switch in the form of register controls transmission gate or outside piece, improve flexibility.In addition, being situated between
What is continued is used to control the resistance R of zoom factor2It can be realized in the form of variable resistance outside piece, it can be more neatly in 21-201
Between traverse value, improve the value flexibility of β.
The present embodiment can be widely used in the extension of the most of CDC circuit range abilities of industry, especially suitable for Sigma
The CDC circuit that Delta form is realized.
It should be understood by those skilled in the art that, embodiments herein can provide as method, system or computer program
Product.Therefore, complete hardware embodiment, complete software embodiment or reality combining software and hardware aspects can be used in the application
Apply the form of example.Moreover, it wherein includes the computer of computer usable program code that the application, which can be used in one or more,
The computer program implemented in usable storage medium (including but not limited to magnetic disk storage, CD-ROM, optical memory etc.) produces
The form of product.
The application is referring to method, the process of equipment (system) and computer program product according to the embodiment of the present application
Figure and/or block diagram describe.It should be understood that every one stream in flowchart and/or the block diagram can be realized by computer program instructions
The combination of process and/or box in journey and/or box and flowchart and/or the block diagram.It can provide these computer programs
Instruct the processor of general purpose computer, special purpose computer, Embedded Processor or other programmable data processing devices to produce
A raw machine, so that being generated by the instruction that computer or the processor of other programmable data processing devices execute for real
The device for the function of being specified in present one or more flows of the flowchart and/or one or more blocks of the block diagram.
These computer program instructions, which may also be stored in, is able to guide computer or other programmable data processing devices with spy
Determine in the computer-readable memory that mode works, so that it includes referring to that instruction stored in the computer readable memory, which generates,
Enable the manufacture of device, the command device realize in one box of one or more flows of the flowchart and/or block diagram or
The function of being specified in multiple boxes.
These computer program instructions also can be loaded onto a computer or other programmable data processing device, so that counting
Series of operation steps are executed on calculation machine or other programmable devices to generate computer implemented processing, thus in computer or
The instruction executed on other programmable devices is provided for realizing in one or more flows of the flowchart and/or block diagram one
The step of function of being specified in a box or multiple boxes.
The above described is only a preferred embodiment of the present invention, being not that the invention has other forms of limitations, appoint
What those skilled in the art changed or be modified as possibly also with the technology contents of the disclosure above equivalent variations etc.
Imitate embodiment.But without departing from the technical solutions of the present invention, according to the technical essence of the invention to above embodiments institute
Any simple modification, equivalent variations and the remodeling made, still fall within the protection scope of technical solution of the present invention.
Claims (9)
1. a kind of scaling circuit that can be used for expanding capacitive digital converter range, which is characterized in that including the first phase inverter,
Two phase inverters, integrating phase switch, sample phase switches, amplifier, resistance R1, capacitor eliminate matrix module and capacitor scaling
Resistor matrix module；
One end of first phase inverter is connected to one end of integrating phase switch, the other end difference of the integrating phase switch
It is connected to one end of sample phase switches, one end of capacitor elimination matrix module, the other end difference of the sample phase switches
It is connected to the output end and negative input end of amplifier, the capacitor eliminates another termination virtual earth of matrix module；The amplifier is just
Input terminal is separately connected one end of one end of resistance R1, capacitor scaling resistor matrix module, the other end connection of the resistance R1
To one end of the second phase inverter, the other end of second phase inverter is separately connected the other end of the first phase inverter, capacitor scaling
The other end of resistor matrix module；
Wherein, the other end of sample phase switches and capacitor eliminate input terminal of the other end of matrix module as scaling circuit,
To access testing capacitance Csensor；Output end of the other end of second phase inverter as scaling circuit, to connect CDC
Circuit.
2. a kind of scaling circuit that can be used for expanding capacitive digital converter range according to claim 1, feature exist
In it includes first capacitor control switch S1, the second capacitance controlled switches S2, third Capacity control that the capacitor, which eliminates matrix module,
Switch S3, the 4th capacitance controlled switches S4, first capacitor C1, the second capacitor C2, third capacitor C3 and the 4th capacitor C4；Institute
State one end of first capacitor control switch S1, one end of the second capacitance controlled switches S2, third capacitance controlled switches S3 one end
And the 4th capacitance controlled switches S4 one end be connected and as the capacitor eliminate matrix module one end；The first capacitor
The other end of control switch S1, the other end of the second capacitance controlled switches S2, third capacitance controlled switches S3 the other end and
The other end of 4th capacitance controlled switches S4 is electric with one end of the first capacitor C1, one end of the second capacitor C2, third respectively
Hold C3 one end and the 4th capacitor C4 one end be connected, the other end of the first capacitor C1, the second capacitor C2 the other end,
The other end of third capacitor C3 and the other end of the 4th capacitor C4 are connected and eliminate the other end of matrix as the capacitor.
3. a kind of scaling circuit that can be used for expanding capacitive digital converter range according to claim 1, feature exist
In the capacitor scaling resistor matrix module includes the first scaling resistance control switch Sw1, the second scaling resistance control switch
Sw2, third scaling resistance control switch Sw3, the 4th scaling resistance control switch Sw4, the first scaling resistance Rx1, the second scaling
Resistance Rx2, the third scaling of scaling resistance Rx3 and the 4th resistance Rx4；One end of the first scaling resistance Rx1, the second scaling
One end of one end of resistance Rx2, one end of third scaling resistance Rx3 and the 4th scaling resistance Rx4 is connected and as the electricity
Hold one end of scaling resistor matrix module；It is described first scaling resistance Rx1 the other end, second scaling resistance Rx2 the other end,
The other end of the other end and the 4th scaling resistance Rx4 that third scales resistance Rx3 scales resistance control switch with first respectively
One end of Sw1, second scaling resistance control switch Sw2 one end, third scaling resistance control switch Sw3 one end and the 4th
The one end for scaling resistance control switch Sw4 is connected；The other end, the second scaling electricity of the first scaling resistance control switch Sw1
Hinder the other end of control switch Sw2, the other end of third scaling resistance control switch Sw3 and the 4th scaling resistance control switch
The other end of Sw4 is connected and the other end as capacitor scaling resistor matrix module.
4. a kind of scaling circuit that can be used for expanding capacitive digital converter range according to claim 3, feature exist
In, the capacitor scaling resistor matrix module further includes that slide rheostat Rx interface and slide rheostat access switch Sw interface,
Switch Sw is accessed to external slide rheostat Rx and slide rheostat；Wherein slide rheostat Rx interface connects with slide rheostat
The both ends that the capacitor scales resistor matrix module are attempted by after entering switch Sw interface concatenation.
5. a kind of scaling circuit that can be used for expanding capacitive digital converter range according to claim 1, feature exist
In the capacitor scaling resistor matrix module includes that slide rheostat Rx and slide rheostat access switch Sw, and the sliding becomes
The one end for hindering device Rx is connected with one end of slide rheostat access switch Sw, the other end conduct of the slide rheostat Rx
The other end of one end of the capacitor scaling resistor matrix module, the slide rheostat access switch Sw contracts as the capacitor
The other end of electric discharge resistance matrix module.
6. a kind of scaling circuit that can be used for expanding capacitive digital converter range according to claim 3, feature exist
In first phase inverter, the second phase inverter, integrating phase switch, sample phase switches, amplifier, resistance R1, capacitor eliminate square
Array module, capacitor scaling resistor matrix module and CDC circuit are integrated in piece.
7. a kind of scaling circuit that can be used for expanding capacitive digital converter range according to claim 4, feature exist
In first phase inverter, the second phase inverter, integrating phase switch, sample phase switches, amplifier, resistance R1, capacitor eliminate square
Array module and CDC circuit are integrated in piece, the slide rheostat Rx interface in capacitor scaling resistor matrix module with
Slide rheostat accesses switch Sw interface and is arranged outside piece, remaining component in capacitor scaling resistor matrix module is integrated in piece
It is interior.
8. a kind of scaling circuit that can be used for expanding capacitive digital converter range according to claim 5, feature exist
In first phase inverter, the second phase inverter, integrating phase switch, sample phase switches, amplifier, resistance R1, capacitor eliminate square
Array module and CDC circuit are integrated in piece, and the capacitor scaling resistor matrix module is arranged outside piece.
9. a kind of based on the described in any item scaling circuits that can be used for expanding capacitive digital converter range of claim 1-8
Method, it is characterised in that: capacitance is carried out to the capacitor to be read using capacitor scaling resistor matrix module and is integrally reduced, then
Matrix module is eliminated using capacitor and eliminates starting capacitor, the capacitor input capacitance digital quantizer that will be obtained by previous processed
It is measured in CDC circuit.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113848388A (en) * | 2021-08-18 | 2021-12-28 | 东风电驱动系统有限公司 | Method and system for realizing resistor digitization by adopting parallel connection of matrix resistors |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103888128A (en) * | 2014-04-03 | 2014-06-25 | 中国科学院半导体研究所 | Array capacitive sensor interface circuit based on interleaving timing sequence detection cancellation mechanism |
| WO2017046782A1 (en) * | 2015-09-17 | 2017-03-23 | King Abdullah University Of Science And Technology | Inverter-based successive approximation capacitance-to-digital converter |
| CN108199718A (en) * | 2018-03-30 | 2018-06-22 | 福州大学 | Capacitance sensor detection method based on Sigma-Delta modulation |
| CN209881744U (en) * | 2019-06-18 | 2019-12-31 | 福州大学 | Scaling circuit capable of being used for enlarging measuring range of capacitance-to-digital converter |
-
2019
- 2019-06-18 CN CN201910527514.5A patent/CN110166010B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103888128A (en) * | 2014-04-03 | 2014-06-25 | 中国科学院半导体研究所 | Array capacitive sensor interface circuit based on interleaving timing sequence detection cancellation mechanism |
| WO2017046782A1 (en) * | 2015-09-17 | 2017-03-23 | King Abdullah University Of Science And Technology | Inverter-based successive approximation capacitance-to-digital converter |
| CN108199718A (en) * | 2018-03-30 | 2018-06-22 | 福州大学 | Capacitance sensor detection method based on Sigma-Delta modulation |
| CN209881744U (en) * | 2019-06-18 | 2019-12-31 | 福州大学 | Scaling circuit capable of being used for enlarging measuring range of capacitance-to-digital converter |
Non-Patent Citations (1)
| Title |
|---|
| 肖小霞;魏榕山;: "电容式湿度传感器读出电路的设计", 中国集成电路, no. 05 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113848388A (en) * | 2021-08-18 | 2021-12-28 | 东风电驱动系统有限公司 | Method and system for realizing resistor digitization by adopting parallel connection of matrix resistors |
| CN113848388B (en) * | 2021-08-18 | 2024-03-12 | 东风电驱动系统有限公司 | Method and system for realizing resistance digitalization by adopting matrix resistor parallel connection |
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