CN105406822B - Switching capacity type band logical feedforward sigma delta modulators - Google Patents
Switching capacity type band logical feedforward sigma delta modulators Download PDFInfo
- Publication number
- CN105406822B CN105406822B CN201510867512.2A CN201510867512A CN105406822B CN 105406822 B CN105406822 B CN 105406822B CN 201510867512 A CN201510867512 A CN 201510867512A CN 105406822 B CN105406822 B CN 105406822B
- Authority
- CN
- China
- Prior art keywords
- resonator
- path
- output
- signal
- input
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 230000001133 acceleration Effects 0.000 claims abstract description 6
- 238000005070 sampling Methods 0.000 claims description 46
- 230000005540 biological transmission Effects 0.000 claims description 14
- 238000000034 method Methods 0.000 claims description 7
- 238000013461 design Methods 0.000 claims description 6
- 230000008054 signal transmission Effects 0.000 claims description 4
- 101100445834 Drosophila melanogaster E(z) gene Proteins 0.000 claims description 2
- 238000004088 simulation Methods 0.000 abstract description 5
- 238000013139 quantization Methods 0.000 abstract description 3
- 230000009897 systematic effect Effects 0.000 abstract description 3
- 238000010586 diagram Methods 0.000 description 5
- 238000005516 engineering process Methods 0.000 description 3
- 125000002950 monocyclic group Chemical group 0.000 description 3
- 238000012546 transfer Methods 0.000 description 3
- 238000006243 chemical reaction Methods 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 238000012545 processing Methods 0.000 description 2
- 238000004458 analytical method Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000005265 energy consumption Methods 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 238000012544 monitoring process Methods 0.000 description 1
- 230000010355 oscillation Effects 0.000 description 1
- 238000007493 shaping process Methods 0.000 description 1
- 230000005236 sound signal Effects 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03C—MODULATION
- H03C1/00—Amplitude modulation
- H03C1/52—Modulators in which carrier or one sideband is wholly or partially suppressed
Landscapes
- Compression, Expansion, Code Conversion, And Decoders (AREA)
Abstract
The invention discloses a kind of band logical feedforward sigma delta modulators, including the switching capacity resonator modules of three cascades, adder Module, quantizer module, feedback DAC module.This sigma delta modulators employ feed-forward type structure and substitute common feedback-type structure, the input terminal of resonator is set only to include quantization noise components, not comprising input signal component, so as to reduce the incoming level of resonator, the loop stability of overall sigma delta modulators is improved.Therefore band logical feedforward sigma delta modulators proposed by the present invention are suitable for the analog-digital converter of high-order single ring architecture, and reduce requirement of the modulator circuit to the simulation sub-circuit such as amplifier.Obtained by simulation result, band logical proposed by the present invention feedovers sigma delta modulators in 3.3V supply voltages, clock frequency 800KHz, centre frequency 200KHz, reach 96.8dB signal-to-distortion ratios and the dynamic range of 106dB under conditions of signal bandwidth 5KHz, meet the micro mechanical sensor systematic difference requirement such as high-precision gyroscope, acceleration transducer.
Description
Technical field
The invention belongs to technical field of integrated circuits, and in particular to a kind of switching capacity type band logical feed forward architecture sigma-
Delta modulator.
Background technology
Digital circuit has that speed is fast, low in energy consumption, high reliability, at Digital Electronic Technique and digital signal
Reason technology obtains fast-developing, more and more electronic equipments, or even is required for believing numeral including micro mechanical sensor system
Number handled.For electronic equipment during work, signal to be dealt with is often the analog variable of consecutive variations, such as temperature
Degree, pressure, acceleration etc. are all analog quantitys, the analog quantitys of these nonnumeric signals first to become by sensor voltage signal or
Person's current signal, is then converted into the digital quantity of certain precision by analog-digital converter, can be sent to computer and be handled.
In recent years, the micro mechanical sensor system such as more and more gyroscopes and acceleration transducer, which is applied, is positioning, is leading
The fields such as boat, seismic monitoring, automotive electronics.The analog signal of these sensing systems collection is, it is necessary to be converted to high-precision number
Word signal is with for carrying out Digital Signal Processing.And the precision of analog-digital converter is as one of bottleneck of system overall precision.
Analog-digital converter based on sigma-delta modulation utilizes over-sampling and noise shaping techniques, enormously simplify mould
Intend the design of circuit, to the imperfection relative insensitivity of analog circuit, relatively simple mould is exchanged for complicated digital circuit
Intend circuit.Therefore, sigma-delta analog-digital converters can with relatively low into obtaining high resolution ratio (more than 16) originally,
It is very suitable for high-precision low bandwidth application.
Current most sigma-delta modulator is all positioned at the audio signal within processing low frequency 20KHz bandwidth.
However, in many micro mechanical sensor systems, transmission signal is located higher than within the arrowband of audio bandwidth.Other digital-to-analogues turn
Technology is changed, such as SAR ADC, production by assembly line are extremely difficult to more than 12 bits turn due to reasons such as manufacturing process
Precision is changed, therefore band logical high accuracy sigma-delta modulator is more suitable for carrying out the analog signal that micro mechanical sensor produces
Analog-to-digital conversion.
Sigma-delta modulator is divided according to loop structure, can be divided into single ring architecture and cascade structure.Single ring architecture
Sigma-delta modulator there is, but the single ring architecture modulator of high-order insensitive to circuit non-ideal characteristic
There are system instability.For sigma-delta modulator, exponent number is higher, better to the filtration result of quantizing noise, but
It is according to theory analysis, higher than monocyclic 1 quantization sigma-delta modulator of second order, it is impossible to mathematically release one
Stability condition.
Using behavior simulation it can be proved that when input signal or resonator original state exceed a certain range, bandpass modulation
Vibration then occurs in device, moreover, after signal returns to stable input range, overshoot oscillation will not disappear.
The content of the invention
The present invention provides a kind of switching capacity type band logical feedforward sigma-delta modulator, low pass sigma- is being overcome
While the bandwidth limitation of delta modulator, using monocyclic feed forward architecture, simplify circuit, and improve system stability.
A kind of switching capacity type band logical feedforward sigma-delta modulator, including：
It can be used for the first resonator for receiving input signal and feedback signal；
It can be used for the second resonator for receiving the output of first resonator；
It can be used for the 3rd resonator for receiving the output of second resonator；
It can be used to receive the first forward path from the input signal, the first resonance from first resonator
Path, the second resonant path from second resonator and the 3rd resonant path from the 3rd resonator
Adder；
Energy receives the quantizer of the output of the adder；
The connection of the first forward path from the input signal of described band logical feedforward sigma-delta modulator the
One forward direction scaling, the first resonant path from first resonator connect the second forward direction scaling and the first weighting scaling, come
The 3rd forward direction scaling is connected from the second resonant path of second resonator and the second weighting scales, from the 3rd resonance
3rd resonant path of device is all connected with the 3rd weighting scaling, and the feedback path connection feedback of the output from the DAC scales, on
Each signal unit for scaling is stated, to ensure loop filter stability；
First forward path of the input signal connects the first input port of the adder, first resonator
First resonant path of output is scaled by the first weighting, connects the second input port of the adder, second resonance
Second resonant path of device output is scaled by the second weighting, connects the 3rd input port of the adder, the described 3rd is humorous
3rd resonant path of the device that shakes output is scaled by the 3rd weighting, connects the 4th input port of the adder；
Outgoing route from the output signal connects the input port of the feedback DAC, the output from DAC it is anti-
Feeder footpath is scaled by feedback, connects the input port of first resonator, forms feedback control loop.
The band logical feedforward sigma-delta modulator uses low-pass prototype design method, i.e., first designs corresponding low pass
The noise transmission function NTF and signal transmission function STF of modulator, the corresponding structure of reselection, is then asked according to NTF and STF
Go out structural coefficient, finally according to Z-1→-Z-2Method band-pass modulator is transformed into bandpass modulation device, f0For signal center's frequency
Rate, fSFor sample frequency, f at this time0With fSMeet relation：f0=fS/4；
The signal transmission function H of the band logical feedforward sigma-delta modulatorS(z) it is：HS(z)=1；
The noise transmission function H of the band logical feedforward sigma-delta modulatorE(z) it is：
Wherein Hf(z) it is the fl transmission function of the sigma-delta modulator；
The input signal of described band logical feedforward sigma-delta modulator is X (z), and output signal is Y (z), the amount
It is E (z) to change the quantizing noise that device introduces, so the input signal RI of first resonator1(z) it is：RI1(z)=X (z)-Y
(z), because Y (z)=HS(z)·X(z)+HE(z) E (z), so RI1(z)=- HE(z)·E(z)。
First resonator of the band logical feedforward sigma-delta modulator, can be used to receive the quantizer
Output and the input signal；First resonator does not overlap clock control by three-phase；Include sampling phase, resonance phase
Position, storage three operating phases of phase；Resonant frequency is located at a quarter of clock frequency.
First, second, third resonator is all inputted using fully differential, includes positive input path, negative input road
Two, footpath input path, each path that inputs include the first positive sampling branch, the second positive sampling branch, the sampling of the 3rd positive
The mutually isostructural sampling branch of branch three, each branch that samples include a sampling switch, a sampling capacitance and three
Transmitting switch, the sampling switch and transmitting switch are equipped with switch input terminal, switch control terminal and output switching terminal；Using complete
Difference output, comprising two positive outgoing route, negative outgoing route outgoing routes, each outgoing route includes three identical knots
The resonant branch of structure, each resonant branch include four transmitting switches, a resonant capacitance.
The present invention provides a kind of method for being used in band logical feedovers sigma-delta modulator handle signal, including：
Feedback signal and input signal are received at the first resonator；
The output from first resonator is received at the second resonator；
The output from second resonator is received at the 3rd resonator；
The output from first resonator, the output from second resonator are received at adder, is come from
The output of 3rd resonator and the input signal；
Via quantizer by output feed back to the sample circuit and from the band logical feedover sigma-delta modulator
Output.
First resonator, can be used to receiving the output of the quantizer and the input signal, by three-phase
Clock control is not overlapped, includes sampling phase, resonance phase, storage three operating phases of phase；Resonant frequency is located at clock frequency
The a quarter of rate.
Beneficial effects of the present invention：By reasonably selecting the coefficient of loop filter, condition stability can be realized
The monocyclic sigma-delta modulator of high-order.That is when input signal of the higher order modulator per level-one is limited in a certain range
Work interior, that higher order modulator can be stablized.
This sigma-delta modulator employs feed-forward type structure and substitutes common feedback-type structure, makes the defeated of resonator
Enter end and only include quantization noise components, not comprising input signal component, so as to reduce the incoming level of resonator, improve whole
The loop stability of body sigma-delta modulator.Therefore band logical feedforward sigma-delta modulator proposed by the present invention is adapted to
In the analog-digital converter of high-order single ring architecture, and reduce requirement of the modulator circuit to the simulation sub-circuit such as amplifier.By imitating
True result obtains, and band logical feedforward sigma-delta modulator proposed by the present invention is in 3.3V supply voltages, clock frequency 800KHz,
Reach 96.8dB signal-to-distortion ratios and the dynamic range of 106dB under conditions of centre frequency 200KHz, signal bandwidth 5KHz, meet
The requirement of the micro mechanical sensor such as high-precision gyroscope, acceleration transducer systematic difference.
Brief description of the drawings
Fig. 1 is a kind of structure chart of switching capacity type band logical of the present invention feedforward sigma-delta modulator；
Fig. 2 is the clock signal of system CLK, and clock controller produces the not overlapping CKA phase clocks of three-phase, CKB phases
Clock, CKC phase clocks；
Fig. 3 is the circuit structure diagram of the switching capacity resonator；
Fig. 4 is resonator works state flow chart；
Fig. 5 is band logical feedforward sigma-delta modulator circuit structure diagram.
Embodiment
Embodiment that the present invention will be described in detail below in conjunction with the accompanying drawings, but the present invention is not limited to this.
As shown in Figure 1, a kind of switching capacity type band logical feedforward sigma-delta modulator, including：
It can be used for the first resonator for receiving input signal and feedback signal；
It can be used for the second resonator for receiving the output of first resonator；
It can be used for the 3rd resonator for receiving the output of second resonator；
It can be used to receive the first forward path from the input signal, the first resonance from first resonator
Path, the second resonant path from second resonator and the 3rd resonant path from the 3rd resonator
Adder；
Energy receives the quantizer of the output of the adder；
The connection of the first forward path from the input signal of described band logical feedforward sigma-delta modulator the
One forward direction scaling, the first resonant path from first resonator connect the second forward direction scaling and the first weighting scaling, come
The 3rd forward direction scaling is connected from the second resonant path of second resonator and the second weighting scales, from the 3rd resonance
3rd resonant path of device is all connected with the 3rd weighting scaling, and the feedback path connection feedback of the output from the DAC scales, on
Each signal unit for scaling is stated, to ensure loop filter stability；
First forward path of the input signal connects the first input port of the adder, first resonator
First resonant path of output is scaled by the first weighting, connects the second input port of the adder, second resonance
Second resonant path of device output is scaled by the second weighting, connects the 3rd input port of the adder, the described 3rd is humorous
3rd resonant path of the device that shakes output is scaled by the 3rd weighting, connects the 4th input port of the adder；
Outgoing route from the output signal connects the input port of the feedback DAC, the output from DAC it is anti-
Feeder footpath is scaled by feedback, connects the input port of first resonator, forms feedback control loop.
The clock when resonator of the band logical feedforward sigma-delta modulator is not overlapped by three-phase as shown in Figure 2
System；Include sampling phase, resonance phase, storage three operating phases of phase；Resonant frequency is located at a quarter of clock frequency.
A kind of switching capacity resonator, its circuit structure diagram as shown in Figure 3, including positive input path 31, negative is defeated
Enter path 32, positive outgoing route 33, negative outgoing route 34, operational amplifier 35.35 be fully differential structure operational amplifier,
Include normal phase input end, negative-phase input, positive output end, negative output end.
The negative-phase input of 31 connection described 35, the normal phase input end of 32 connection described 35,33 connection
Described 35 positive output end, the negative output end of 34 connection described 35.
Described 31 is identical with 32 structure, 31 sample branch 311 comprising the first positive, the second positive samples branch 312,
3rd positive samples branch 313；32 adopt comprising the first negative sampling branch 321, the second negative sampling branch 322, the 3rd negative
Sample branch 323.
Described 33 is identical with 34 structure, 33 comprising the first positive resonant branch 331, the second positive resonant branch 332,
3rd positive resonant branch 333；34 is humorous comprising the first negative resonant branch 341, the second negative resonant branch 342, the 3rd negative
Shake branch 343.
Positive phase input signal is connected to the input terminal of 311,312,313 sampling switch, and negative input signal is connected to
321st, the input terminal of 322,323 sampling switch.
311st, the control terminal connection control clock path CKA of 321 sampling switch, the control of 312,322 sampling switch
End connection control clock path CKB, the control terminal connection control clock path CKC of 313,323 sampling switch.
311st, the output terminal of 321 sampling switch connects the anode and 311,321 of 311,321 sampling capacitance respectively
The output terminal of transmitting switch one.In first resonator, the input terminal of 311 transmitting switch one connects the feedback DAC
Negative sense feedback path, the input terminal of 321 transmitting switch one connects the positive feedback path of the feedback DAC；Described
In two resonators and the 3rd resonator, the input terminal connection common mode electrical level of 311,321 transmitting switch one.311st, 321 transmission
The control terminal connection control clock path CKB of switch one.311st, the negative terminal of 321 sampling capacitance connects 311,321 biography respectively
The input terminal of the output terminal and transmitting switch three of defeated switch two.311st, the input terminal connection common mode electrical level of 321 transmitting switch two,
311st, the control terminal connection control clock path CKA of 321 transmitting switch two.311st, the control terminal of 321 transmitting switch three connects
Connect and control clock path CKB, the negative-phase input of the output terminal connection operational amplifier of 311 transmitting switch three, 321
The output terminal of transmitting switch three connects the normal phase input end of the operational amplifier.
312nd, the output terminal of 322 sampling switch connects the anode and 312,322 of 312,322 sampling capacitance respectively
The output terminal of transmitting switch one.In first resonator, the input terminal of 312 transmitting switch one connects the feedback DAC
Negative sense feedback path, the input terminal of 322 transmitting switch one connects the positive feedback path of the feedback DAC；Described
In two resonators and the 3rd resonator, the input terminal connection common mode electrical level of 312,322 transmitting switch one.312nd, 322 transmission
The control terminal connection control clock path CKC of switch one.312nd, the negative terminal of 322 sampling capacitance connects 312,322 biography respectively
The input terminal of the output terminal and transmitting switch three of defeated switch two.312nd, the input terminal connection common mode electrical level of 322 transmitting switch two,
312nd, the control terminal connection control clock path CKB of 322 transmitting switch two.311st, the control terminal of 321 transmitting switch three connects
Connect and control clock path CKC, the negative-phase input of the output terminal connection operational amplifier of 312 transmitting switch three, 322
The output terminal of transmitting switch three connects the normal phase input end of the operational amplifier.
313rd, the output terminal of 323 sampling switch connects the anode and 313,323 of 313,323 sampling capacitance respectively
The output terminal of transmitting switch one.In first resonator, the input terminal of 313 transmitting switch one connects the feedback DAC
Negative sense feedback path, the input terminal of 323 transmitting switch one connects the positive feedback path of the feedback DAC；Described
In two resonators and the 3rd resonator, the input terminal connection common mode electrical level of 313,323 transmitting switch one.313rd, 323 transmission
The control terminal connection control clock path CKA of switch one.313rd, the negative terminal of 323 sampling capacitance connects 313,323 biography respectively
The input terminal of the output terminal and transmitting switch three of defeated switch two.313rd, the input terminal connection common mode electrical level of 323 transmitting switch two,
313rd, the control terminal connection control clock path CKC of 323 transmitting switch two.313rd, the control terminal of 323 transmitting switch three connects
Control clock path CKA is met, the output terminal of 313 transmitting switch three connects described 35 negative-phase input, 323 transmitting switch
Three output terminal connects described 35 normal phase input end.
The control terminal connection control clock path CKC of described 331,341 the first transmitting switch；331 the first transmission is opened
The input terminal of pass connects described 35 negative-phase input, and the positive of the input terminal connection described 35 of 341 the first transmitting switch is defeated
Enter end；331st, the output terminal of 341 the first transmitting switch connects the anode of 331,341 resonant capacitance respectively.Described 331,341
The second transmitting switch control terminal connection control clock path CKA；The input terminal connection described 35 of 331 the second transmitting switch
Normal phase input end, the input terminal of 341 the second transmitting switch connects described 35 negative-phase input；331st, the second of 341 passes
The output terminal of defeated switch connects the anode of 331,341 resonant capacitance respectively.The control of described 331,341 the 3rd transmitting switch
End connection control clock path CKA；331st, the input terminal of 341 the 3rd transmitting switch connects 331,341 resonant capacitance respectively
Negative terminal；331st, the output terminal connection common mode electrical level of 341 the 3rd transmitting switch.Described 331,341 the 4th transmitting switch
Control terminal connection control clock path CKC；331st, the input terminal of 341 the 4th transmitting switch connects 331,341 resonance respectively
The negative terminal of capacitance；The output terminal of 331 the 4th transmitting switch connects described 35 positive output end；341 the 4th transmitting switch
Output terminal connect described 35 negative output end.
The control terminal connection control clock path CKB of described 332,342 the first transmitting switch；332 the first transmission is opened
The input terminal of pass connects described 35 negative-phase input, and the positive of the input terminal connection described 35 of 342 the first transmitting switch is defeated
Enter end；332nd, the output terminal of 342 the first transmitting switch connects the anode of 332,342 resonant capacitance respectively.Described 332,342
The second transmitting switch control terminal connection control clock path CKC；The input terminal connection described 35 of 332 the second transmitting switch
Normal phase input end, the input terminal of 342 the second transmitting switch connects described 35 negative-phase input；332nd, the second of 342 passes
The output terminal of defeated switch connects the anode of 332,342 resonant capacitance respectively.The control of described 332,342 the 3rd transmitting switch
End connection control clock path CKC；332nd, the input terminal of 342 the 3rd transmitting switch connects 332,342 resonant capacitance respectively
Negative terminal；332nd, the output terminal connection common mode electrical level of 342 the 3rd transmitting switch.Described 332,342 the 4th transmitting switch
Control terminal connection control clock path CKB；332nd, the input terminal of 342 the 4th transmitting switch connects 332,342 resonance respectively
The negative terminal of capacitance；The output terminal of 332 the 4th transmitting switch connects described 35 positive output end；342 the 4th transmitting switch
Output terminal connect described 35 negative output end.
The control terminal connection control clock path CKA of described 333,343 the first transmitting switch；333 the first transmission is opened
The input terminal of pass connects described 35 negative-phase input, and the positive of the input terminal connection described 35 of 343 the first transmitting switch is defeated
Enter end；333rd, the output terminal of 343 the first transmitting switch connects the anode of 333,343 resonant capacitance respectively.Described 333,343
The second transmitting switch control terminal connection control clock path CKB；The input terminal connection described 35 of 333 the second transmitting switch
Normal phase input end, the input terminal of 343 the second transmitting switch connects described 35 negative-phase input；333rd, the second of 343 passes
The output terminal of defeated switch connects the anode of 333,343 resonant capacitance respectively.The control of described 333,343 the 3rd transmitting switch
End connection control clock path CKB；333rd, the input terminal of 343 the 3rd transmitting switch connects 333,343 resonant capacitance respectively
Negative terminal；333rd, the output terminal connection common mode electrical level of 343 the 3rd transmitting switch.Described 333,343 the 4th transmitting switch
Control terminal connection control clock path CKA；333rd, the input terminal of 343 the 4th transmitting switch connects 333,343 resonance respectively
The negative terminal of capacitance；The output terminal of 333 the 4th transmitting switch connects described 35 positive output end；343 the 4th transmitting switch
Output terminal connect described 35 negative output end.
As shown in figure 4, work as the T=n moment, each way switch closures of CKA phases, CKB phases, CKC phases switch off.
Signal inputs sampling switch of the path by the first sampling branch, is connected with the anode of the sampling capacitance of the first sampling branch, defeated
Enter signal to be collected and be stored as Vin (n).The positive and negative both ends of sampling capacitance of second sampling branch disconnect, and still store upper one
The input signal Vin (n-1) at a clock cycle T=n-1 moment.The sampling capacitance negative terminal of 3rd sampling branch passes through transmitting switch
It is connected with opamp input terminal, the input signal Vin (n-2) at T=n-2 moment is transferred to operational amplifier is transported
Calculate.The transmitting switch for the 3rd resonant branch that the output terminal of operational amplifier passes through the resonator connects the 3rd resonant branch
Resonant capacitance anode, the resonant capacitance negative terminal of the 3rd resonant branch by transmitting switch concatenation operation amplifier negative input,
Since the input terminal of amplifier is considered virtual earth, so the output signal at the resonant capacitance storage T=n moment of the 3rd resonant branch
Vout(n).The positive and negative both ends of resonant capacitance of second resonant branch disconnect, and still store moment clock cycle T=n-1
Output signal Vout (n-1).The resonant capacitance negative terminal of 3rd resonant branch passes through transmitting switch and opamp input terminal
Connection, is transferred to operational amplifier by the output signal Vout (n-2) at T=n-2 moment and carries out computing.
Then have in T=n moment, output terminal：Vout (n)=- Vin (n-2)-Vout (n-2)；
At the T=n+1 moment, output terminal has：Vout (n+1)=- Vin (n-1)-Vout (n-1)；
At the T=n+2 moment, output terminal has：Vout (n+2)=- Vin (n)-Vout (n).
The resonator transfer function is expressed as in Z domains：
It is as low-pass filter, the transfer function of integrator using integrator in band-pass modulator
Therefore the resonator completes the Z by band-pass modulator to bandpass modulation device-1→-Z-2Conversion.The resonator is without additionally adding
Add delay unit, so being adapted to form feed forward architecture band logical sigma-delta modulator.
The switching capacity resonator used in other inventions only samples two sampling branches, its transfer function is：Need additionally to add delay unit, increase design complexities.
A kind of band logical feedovers sigma-delta modulator, its circuit structure diagram is as shown in Figure 5, including described first humorous
Shake device 51, second resonator 52, the 3rd resonator 53, the adder 54, the quantizer 55, the feedback
DAC56。
First forward path of the input signal, connection described 51 input port, 51 output port connection described in
First resonant path；First resonant path connects described 52 input port, and 52 output port connection described second is humorous
Shake path；Second resonant path connects described 53 input port, and 53 output port connects the 3rd resonant path.
First forward path of the input signal connects described 54 first input port, and first resonant path connects
Connect 54 the second input port, the 3rd input port of the second resonant path connection 54, the 3rd resonant path connection
54 the 4th input port.
55 input port described in described 54 output port.55 be One-bit quantizers, i.e. comparator.55 output is
The overall output signal D0 of modulator, and the anti-phase D0B of overall output signal.
Since described 55 be One-bit quantizers, so 56 be single-bit DAC, 56 can be formed with 4 MOS switches.56
Include 561,562 two PMOS switches and 563,564 two nmos switches.The source of each MOS switch is as input terminal, grid
End is used as control terminal, and drain terminal is as output terminal.561st, 562 input terminal connection positive reference voltage source, 563,563 input terminal
Connect negative reference voltage source.Positive outgoing route from the output signal D0 connects 561,563 control port；
The negative outgoing route for exporting signal D0B connects 562,564 control port；561st, 563 output port connects 56
Negative feedback path, the positive feedback path of 562,564 output port connection 56.
The circuit diagram of first resonator 51 is as shown in figure 3,56 positive feedback path connects 311,312, the 313 of 51
The input terminal of the transmitting switch one of three positive sampling branches, 321,322,323 3 of 56 negative sense feedback path connection 51
The input terminal of the transmitting switch one of negative sampling branch, thus forms feedback control loop.
Obtained by simulation result, band logical proposed by the present invention feedovers sigma-delta modulator in 3.3V supply voltages, clock
Reach the dynamic of 96.8dB signal-to-distortion ratios and 106dB under conditions of frequency 800KHz, centre frequency 200KHz, signal bandwidth 5KHz
State scope, meets the micro mechanical sensor systematic difference requirement such as high-precision gyroscope, acceleration transducer.
Claims (2)
- The sigma-delta modulator 1. a kind of switching capacity type band logical feedovers, it is characterised in that including：It can be used for the first resonator for receiving input signal and feedback signal；It can be used for the second resonator for receiving the output of first resonator；It can be used for the 3rd resonator for receiving the output of second resonator；It can be used to receive the first forward path from the input signal, the first resonance road from first resonator Footpath, the second resonant path from second resonator and the 3rd resonant path from the 3rd resonator plus Musical instruments used in a Buddhist or Taoist mass；It can be used for the quantizer for receiving the output of the adder；Before the connection of the first forward path from the input signal first of the band logical feedforward sigma-delta modulator The first resonant path to scaling, from first resonator connects the second forward direction scaling and the first weighting scaling, from institute The second resonant path for stating the second resonator connects the 3rd forward direction scaling and the second weighting scaling, from the 3rd resonator 3rd resonant path is all connected with the 3rd weighting scaling, the feedback path connection feedback scaling of the output from DAC, above-mentioned each signal Unit for scaling, to ensure loop filter stability；Further comprise that positioned at feedback path DAC of the reception from the quantizer can be used for, from the output signal Outgoing route connects the input port of the DAC, and the feedback path of the output from the DAC is scaled by feedback, connects institute The input port of the first resonator is stated, forms feedback control loop；The band logical feedforward sigma-delta modulator uses low-pass prototype design method, i.e., first designs corresponding low-pass modulation The noise transmission function NTF and signal transmission function STF of device, the corresponding structure of reselection, then obtains knot according to NTF and STF Structure coefficient, finally according to Z-1→-Z-2Method band-pass modulator is transformed into bandpass modulation device, f0For signal center frequency, fS For sample frequency, f at this time0With fSMeet relation：f0=fS/4；The signal transmission function H of the band logical feedforward sigma-delta modulatorS(z) it is：HS(z)=1；The noise transmission function H of the band logical feedforward sigma-delta modulatorE(z) it is：Wherein Hf(z) it is the fl transmission function of the sigma-delta modulator；The input signal of described band logical feedforward sigma-delta modulator is X (z), and output signal is Y (z), the quantizer The quantizing noise of introducing is E (z), so the input signal RI of first resonator1(z) it is：RI1(z)=X (z)-Y (z), Because Y (z)=HS(z)·X(z)+HE(z) E (z), so RI1(z)=- HE(z)·E(z)；First resonator, can be used to receive exporting and the input signal for the quantizer；First resonator, clock control is not overlapped by three-phase；Include three sampling phase, resonance phase, storage, phase Operating phase；First resonator, resonant frequency are located at a quarter of clock frequency；First, second, third resonator is all inputted using fully differential, includes positive input path, negative input path two A input path, each path that inputs include the first positive sampling branch, the second positive sampling branch, the 3rd positive sampling branch Three mutually isostructural sampling branches, each branch that samples include a sampling switch, a sampling capacitance and three transmission Switch, the sampling switch and transmitting switch are equipped with switch input terminal, switch control terminal and output switching terminal；Using fully differential Output, comprising two positive outgoing route, negative outgoing route outgoing routes, each outgoing route is mutually isostructural comprising three Resonant branch, each resonant branch include four transmitting switches, a resonant capacitance.
- A kind of 2. application of band logical feedforward sigma-delta modulator as claimed in claim 1, it is characterised in that the tune Device processed is integrated into gyroscope, acceleration transducer.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510867512.2A CN105406822B (en) | 2015-12-01 | 2015-12-01 | Switching capacity type band logical feedforward sigma delta modulators |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510867512.2A CN105406822B (en) | 2015-12-01 | 2015-12-01 | Switching capacity type band logical feedforward sigma delta modulators |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN105406822A CN105406822A (en) | 2016-03-16 |
| CN105406822B true CN105406822B (en) | 2018-04-20 |
Family
ID=55472119
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201510867512.2A Active CN105406822B (en) | 2015-12-01 | 2015-12-01 | Switching capacity type band logical feedforward sigma delta modulators |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN105406822B (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106788444A (en) * | 2016-12-12 | 2017-05-31 | 浙江大学 | The low pass sigma Delta modulator without sinad ratio spuious, high is realized simultaneously |
| CN108242937B (en) * | 2016-12-15 | 2021-07-09 | 通用汽车环球科技运作有限责任公司 | Multi-rate energy efficient Delta-sigma converter |
| CN109212258B (en) * | 2017-07-03 | 2021-04-13 | 无锡华润上华科技有限公司 | Front-end circuit of accelerometer and acceleration signal processing method |
| CN111988037B (en) * | 2019-05-23 | 2024-07-09 | 中国科学院声学研究所 | Sigma-Delta modulator with capacitor sharing structure |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1470105A (en) * | 2000-09-18 | 2004-01-21 | �����ɷ� | Multi-sampling SIGMA-DElTA analog-to-digital converter |
| CN101553987A (en) * | 2006-12-08 | 2009-10-07 | 罗伯特·博世有限公司 | Bandpass sigma-delta analogue/digital converter for converting an if signal |
| CN101640539A (en) * | 2009-06-19 | 2010-02-03 | 浙江大学 | Sigma-delta analog-to-digital converter |
-
2015
- 2015-12-01 CN CN201510867512.2A patent/CN105406822B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1470105A (en) * | 2000-09-18 | 2004-01-21 | �����ɷ� | Multi-sampling SIGMA-DElTA analog-to-digital converter |
| CN101553987A (en) * | 2006-12-08 | 2009-10-07 | 罗伯特·博世有限公司 | Bandpass sigma-delta analogue/digital converter for converting an if signal |
| CN101640539A (en) * | 2009-06-19 | 2010-02-03 | 浙江大学 | Sigma-delta analog-to-digital converter |
Also Published As
| Publication number | Publication date |
|---|---|
| CN105406822A (en) | 2016-03-16 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP6342071B2 (en) | High-precision flexible accelerometer | |
| EP3104530B1 (en) | Ultra low power dual quantizer architecture for oversampling delta-sigma modulator | |
| CN104579344B (en) | Multi-stage noise shaping analog-digital converter | |
| CN105406822B (en) | Switching capacity type band logical feedforward sigma delta modulators | |
| CN101577549B (en) | Multiple output time-to-digital converter | |
| US20180267482A1 (en) | Time-to-digital converter | |
| CN107852164B (en) | Suppression of signal transfer function peaking in feed-forward delta-sigma converters | |
| US8258990B2 (en) | Integrator, resonator, and oversampling A/D converter | |
| CN109889199B (en) | Sigma delta type and SAR type mixed ADC with chopper stabilization | |
| US9118342B2 (en) | Low power excess loop delay compensation technique for delta-sigma modulators | |
| Caldwell et al. | Incremental data converters at low oversampling ratios | |
| EP3297169A1 (en) | Continuous-time cascaded sigma-delta analog-to-digital | |
| CN102801425A (en) | Dual-voltage-controlled oscillator loop-based Sigma-Delta analog to digital converter | |
| JP7376017B2 (en) | Delta-sigma converter with precharging based on quantizer output code | |
| EP3595178B1 (en) | Continuous time sigma delta modulator | |
| CN103762980A (en) | High-stability sigma-delta modulator structure with improved noise suppression effect | |
| TW201822473A (en) | Sigma delta modulator and signal conversion method thereof | |
| WO2018004617A1 (en) | Neutralizing voltage kickback in a switched capacitor based data converter | |
| KR101559456B1 (en) | A low-power·low-area third order sigma-delta modulator with delayed feed-forward path | |
| Guessab et al. | A passive delta-sigma modulator for low-power applications | |
| CN102244517B (en) | Shared exchange capacitance type integrator and operation method thereof as well as sigma-delta modulator | |
| US10044368B2 (en) | Sigma delta analog to digital converter | |
| WO2021220489A1 (en) | Semiconductor integrated circuit | |
| Mihálov et al. | Implementation of sigma-delta analog to digital converter in FPGA | |
| CN107294537B (en) | Sigma Delta Modulator-based analog-to-digital converter |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |