CN102088275A - Charge domain filter and filtering device - Google Patents

Abstract

The invention relates to a charge domain filter which comprises a phase splitter, a plurality of first switching capacitor networks, a plurality of second switching capacitor networks and a connecting link, wherein the phase splitter receives a first input signal and a second input signal to respectively generate a plurality of first phase splitting signals and a plurality of second phase splitting signals; the first switching capacitor networks respectively are provided with an input end for receiving the first phase splitting signals one by one, and an output end; the second switched capacitor networks respectively are provided with an input end for receiving the second phase splitting signals one by one, and an output end; the interconnecting link is used for configurating a coupling status between the output ends of the first switched capacitor networks and that of the second switched capacitor networks so as to generate a plurality of output signals.

Description

Charge-domain filter and filter

Technical field

The invention relates to a kind of charge-domain filter (charge domain filter).

Background technology

Switched capacitor network (switched-capacitor network) is handled common a kind of circuit in (discrete time signal processing) for discrete-time signal, comprising a plurality of switches and a plurality of electric capacity.By conducting, the described switch of not conducting, the situation of the described electric capacity store charge of user's may command is to handle input signal.

Switched capacitor network is common in the filtering technique.Compared to capacitance resistance formula analogue filter circuit, the filter effect of switched capacitor network mainly by the wherein size ratio decision of each electric capacity, does not need to use accurate electric capacity, resistive element.Therefore, switched capacitor network quite is fit to be made in the chip.

Summary of the invention

The invention provides a kind of charge-domain filter.

In one embodiment, the charge-domain filter comprises a phase splitter, a plurality of first switched capacitor network, a plurality of second switch capacitance network and a connection line.Phase splitter receives one first input signal and one second input signal, to produce about a plurality of first split phase signals of this first input signal and about a plurality of second split phase signals of this second input signal.Described first switched capacitor network is corresponding one to one with described first split phase signal, has an input separately and receives pairing above-mentioned first split phase signal and have an output separately.Described second switch capacitance network is corresponding one to one with described second split phase signal, has an input separately and receives pairing above-mentioned second split phase signal and have an output separately.Connection line is responsible for disposing the situation that couples of the output of the output of above-mentioned first switched capacitor network and above-mentioned second switch capacitance network, to produce a plurality of output signals.

The present invention also discloses a kind of filter of using above-mentioned charge-domain filter.In one embodiment, this filter comprises: the multistage charge-domain filter of serial connection.Charge-domain filters at different levels comprise: a phase splitter, a plurality of first switched capacitor network, a plurality of second switch capacitance network and a connection line.With one-level charge-domain filter wherein is example, wherein: this phase splitter receives one first input signal and one second input signal, to produce about a plurality of first split phase signals of this first input signal and about a plurality of second split phase signals of this second input signal; Described first switched capacitor network is corresponding one to one with described first split phase signal, has an input separately and receives pairing above-mentioned first split phase signal and have an output separately; Described second switch capacitance network is corresponding one to one with described second split phase signal, has an input separately and receives pairing above-mentioned second split phase signal and have an output separately; And this connection line is used to dispose the situation that couples of the above-mentioned output of the above-mentioned output of above-mentioned first switched capacitor network and above-mentioned second switch capacitance network, to produce at least two input signals that output signal is the next stage circuit.

Charge-domain filter of the present invention more can adopt a kind of time-interleaving technology, and this kind charge-domain filter comprises: a phase splitter, organize first switched capacitor network more, organize a second switch capacitance network and a connection line more.This phase splitter receives one first input signal and one second input signal, to produce about a plurality of first split phase signals of this first input signal and about a plurality of second split phase signals of this second input signal.Above-mentioned respectively to organize first switched capacitor network corresponding one to one with described first split phase signal, and above-mentioned first switched capacitor network has an input separately and receives pairing above-mentioned first split phase signal and have an output separately.Above-mentioned respectively to organize the second switch capacitance network corresponding one to one with described second split phase signal, and above-mentioned second switch capacitance network has an input separately and receives pairing above-mentioned second split phase signal and have an output separately.This connection line is used to dispose the situation that couples of the above-mentioned output of the above-mentioned output of above-mentioned first switched capacitor network and above-mentioned second switch capacitance network, to produce a plurality of output signals.

Description of drawings

Please cooperate the detailed description of following accompanying drawing, embodiment, will on address other purpose of the present invention and advantage and be specified in after, wherein:

Fig. 1 is a kind of execution mode of charge-domain filter;

Fig. 2 A and Fig. 2 B are a kind of execution modes of switched capacitor network;

Fig. 3 A is a kind of charge-domain filter 300;

Fig. 3 B is the effect of 300 pairs of anti-phase input signals of charge-domain filter;

Fig. 3 C is the effect of the input signal of 300 pairs of homophases of charge-domain filter;

Fig. 4 A is the frequency response of a kind of IIR design of charge-domain filter 300;

Fig. 4 B is the frequency response of a kind of FIR design of charge-domain filter 300;

Fig. 4 C is the test result of a kind of IIR design of charge-domain filter 300;

Fig. 4 D is the test result of a kind of FIR design of charge-domain filter 300;

Fig. 5 A is a kind of execution mode of this case, wherein adopts superposition charge-domain filter and realizes a filter;

Fig. 5 B is the frequency response of Fig. 5 A filter;

Fig. 6 is the another kind of execution mode of charge-domain filter; And

Fig. 7 is the another kind of execution mode of charge-domain filter, wherein adopts the time-interleaving technology.

Embodiment

Fig. 1 is a charge-domain filter (charge domain filter) 100, comprises a phase splitter 102, a plurality of first switched capacitor network 104_1 ... 104_N, a plurality of second switch capacitance network 106_1 ... a 106_N and a connection line 108.Phase splitter 102 receives one first input signal V1 and one second input signal V2, to produce a plurality of first split phase signal I11 about this first input signal V1 ... I1N and about a plurality of second split phase signal I21 of this second input signal V2 ... I2N.The first switched capacitor network 104_1 ... the 104_N and the first split phase signal I11 ... I1N is corresponding one to one, has an input separately and receives pairing first split phase signal and have an output separately.Second switch capacitance network 106_1 ... the 106_N and the second split phase signal I21 ... I2N is corresponding one to one, has an input separately and receives pairing second split phase signal and have an output separately.Connection line 108 is responsible for the above-mentioned first switched capacitor network 104_1 of configuration ... the output of 104_N and above-mentioned second switch capacitance network 106_1 ... the connection state of the output of 106_N is to produce a plurality of output signal OUT1 ... OUTK.

Phase splitter 102 can have numerous embodiments.A kind of execution mode is realized phase splitter 102 with transduction (transconductance) device, wherein, first and second input signal V1 and V2 are voltage pattern and the described first split phase signal I11 ... I1N and the described second split phase signal I21 ... I2N is the electric current pattern.In addition, also can mixer or other device with phase-splitting function realize phase splitter 102.

Connection line 108 can multiple connected mode connect the above-mentioned first switched-capacitor circuit 104_1 ... 104_N and second switch condenser network 106_1 ... the output of 106_N.Connection line 108 can comprise a plurality of electronic components, circuit or cabling, to connect the above-mentioned first switched-capacitor circuit 104_1 indirectly or directly ... 104_N and second switch condenser network 106_1 ... the output of 106_N, wherein, different interconnection techniques will produce different filter effects.

The switched capacitor network (switched capacitor network) of the single output of any single input all can be used to realize above-mentioned first, second switched-capacitor circuit 104_1 ... 104_N and 106_1 ... 106_N, and switched capacitor network 104_1 ... 104_N and 106_1 ... 106_N need not be realized by the circuit of same pattern entirely.By each switched capacitor network (104_1 in the design charge-domain filter 100 ... 104_N and 106_1 ... structure 106_N) also can produce different filter effects.

Fig. 2 A is the single output of an a kind of single input switched capacitor network 200, and Fig. 2 B is the sequential chart of the control signal of switched capacitor network 200.At control signal clk1 ... under the effect of clkN, switch S 1 ... SN takes turns conducting, makes signal IN to capacitor C 1 ... the CN charging.Then, control signal clk (N+1) makes switch S S1 ... the SSN conducting makes capacitor C o be collected capacitor C 1 ... the charge information that CN is stored.Control signal Re1 is responsible for actuating switch RS1 ... RSN is with replacement capacitor C 1 ... CN.

The switch ENS1 of Fig. 2 A and RS (N+1) are the frequency range that is used for improving filter.Control signal EN is responsible for the state of configuration switch ENS1.During not conducting of ENS1, the electric charge in the capacitor C o can not be reset, and switched capacitor network 200 is infinite impulse response filter (infinite impulse response filter, IIR filter), and frequency range is lower.During the ENS1 conducting, the electric charge in the capacitor C o can be reset with the control signal Re1 of switch RS (N+1), and switched capacitor network 200 is finite impulse response filter (finite impulse response filter, FIR filter), the frequency range broad.Switch ENS2 and capacitor C a control effective capacitance (Ceff), and then the frequency range of control switch capacitance network 200, signal Va will adjust the total capacitance value (Co+Ceff (Ca, Va)) that couples on the output OUT.

Fig. 3 A is the another kind of execution mode of this case charge-domain filter.Charge-domain filter 300 comprises a phase splitter 302, two first switched capacitor network 304_1 and 304_2, two second switch capacitance network 306_1 and a 306_2 and a connection line 308.Phase splitter 302 comprises two transduction device GM1 and GM2.Transduction device GM1 receives the first input signal V1 of voltage pattern, is converted into the one first in-phase signal I11 (with the first input signal V1 homophase) and one first inversion signal I12 (anti-phase with the first input signal V1) of electric current pattern.Transduction device GM2 receives the second input signal V2 of voltage pattern, is converted into the one second in-phase signal I22 (with the second input signal V2 homophase) and one second inversion signal I21 (anti-phase with the second input signal V2) of electric current pattern.Connection line 308 couples the output of the pairing second switch capacitance network of second inversion signal I21 306_2 with the output of the pairing first switched capacitor network 304_1 of the first in-phase signal I11, so that output signal OUT1 to be provided.In addition, connection line 308 couples the output of the pairing second switch capacitance network of second in-phase signal I22 306_1 with the output of the pairing first switched capacitor network 304_2 of the first inversion signal I12, so that output signal OUT2 to be provided.Internal structure by first, second switched capacitor network of appropriate design 304_1,304_2,306_1,306_2, charge-domain filter 300 is the effective filtering signal of specifying frequency range outer (stop-band) not only, and more effectively the common-mode noise (common-mode noise) of (in-band) in the frequency range, asymmetric (mismatch) effect of improving signal and the undesirable signal of elimination even-order are specified in filtering.

Illustrate the effect of Fig. 3 A charge-domain filter 300.The user can make a positive received signal that receiver (receiver) provided and an anti-phase received signal as the first input signal V1 shown in the figure and the second input signal V2.Yet signal V1 and V2 can not be entirely anti-phase signal usually, often have common-mode noise to mix wherein.Can suppose that the first input signal V1 comprises positive data signal+V and positive common-mode noise+N, and the second input signal V2 comprises anti-phase data signal-V and positive common-mode noise+N; In other words, data signal (V) is anti-phase at two inputs of charge-domain filter 300, and common-mode noise (N) is a homophase at two inputs of charge-domain filter 300.When Fig. 3 B signal input end signal is anti-phase, the signal(l)ing condition of its output.Fig. 3 C signal input end signal is same phase time, the signal(l)ing condition of output.

Consult Fig. 3 B, when two input end signals anti-phase (for example, one for just (+), another is negative (-)), then the signal of two outputs be that (+)+(+), is (-)+(-) for strengthening signal-.Otherwise, consult Fig. 3 C, when two input end signal homophases (for example, both are all on the occasion of signal (+)), then signal can on two outputs, cut down-both are all (+)+(-).

The application of the charge-domain filter 300 that this section is described in more detail for example, wherein, first/second switch capacitance network in the charge-domain filter 300 adopts same clock pulse and realizes with the disclosed technology of Fig. 2 A, Fig. 2 B, and the capacitance parameter of the first switched capacitor network 304_1 and 304_2 is adopted subscript p, and the capacitance parameter of second switch capacitance network 306_1 and 306_2 is adopted subscript n.

Input signal V1 and V2 antiphase (as, data signal inverting each other) time, conversion function can be:

No limited pulse filter H _{STF, IIR}(z):

$H_{\mathrm{STF},\mathrm{IIR}}\left(z\right)=\frac{\left(\frac{\underset{i=1}{\overset{P}{\mathrm{\Σ}}}{\mathrm{Cp}}_{P+1-i}{z}^{-(i-1)}}{\mathrm{Cop}+\underset{i=1}{\overset{P}{\mathrm{\Σ}}}{\mathrm{Cp}}_i}\right)}{(1-\frac{\mathrm{Cop}\·z^{-(P+1)}}{\mathrm{Cop}+\underset{i=1}{\overset{P}{\mathrm{\Σ}}}{\mathrm{Cp}}_i})}+\frac{\left(\frac{\underset{i=1}{\overset{N}{\mathrm{\Σ}}}{\mathrm{Cn}}_{N+1-i}{z}^{-(i-1)}}{\mathrm{Con}+\underset{i=1}{\overset{N}{\mathrm{\Σ}}}{\mathrm{Cn}}_i}\right)}{(1-\frac{\mathrm{Con}\·z^{-(N+1)}}{\mathrm{Con}+\underset{i=0}{\overset{N}{\mathrm{\Σ}}}{\mathrm{Cn}}_i})}$

The finite impulse filters H _{STF, FIR}(z):

$H_{\mathrm{STF},\mathrm{FIR}}\left(z\right)=\left(\frac{\underset{i=1}{\overset{P}{\mathrm{\Σ}}}{\mathrm{Cp}}_{P+1-i}{z}^{-(i-1)}}{\mathrm{Cop}+\underset{i=1}{\overset{P}{\mathrm{\Σ}}}{\mathrm{Cp}}_i}\right)+\left(\frac{\underset{i=1}{\overset{N}{\mathrm{\Σ}}}{\mathrm{Cn}}_{N+1-i}{z}^{-(i-1)}}{\mathrm{Con}+\underset{i=1}{\overset{N}{\mathrm{\Σ}}}{\mathrm{Cn}}_i}\right)$

Input signal V1 and V2 same-phase (as, the common-mode noise of homophase each other) time, conversion function can be:

No limited pulse filter H _{NTF, IIR}(z):

$H_{\mathrm{STF},\mathrm{IIR}}\left(z\right)=\frac{\left(\frac{\underset{i=1}{\overset{P}{\mathrm{\Σ}}}{\mathrm{Cp}}_{P+1-i}{z}^{-(i-1)}}{\mathrm{Cop}+\underset{i=1}{\overset{P}{\mathrm{\Σ}}}{\mathrm{Cp}}_i}\right)}{(1-\frac{\mathrm{Cop}\·z^{-(P+1)}}{\mathrm{Cop}+\underset{i=1}{\overset{P}{\mathrm{\Σ}}}{\mathrm{Cp}}_i})}-\frac{\left(\frac{\underset{i=1}{\overset{N}{\mathrm{\Σ}}}{\mathrm{Cn}}_{N+1-i}{z}^{-(i-1)}}{\mathrm{Con}+\underset{i=1}{\overset{N}{\mathrm{\Σ}}}{\mathrm{Cn}}_i}\right)}{(1-\frac{\mathrm{Con}\·z^{-(N+1)}}{\mathrm{Con}+\underset{i=0}{\overset{N}{\mathrm{\Σ}}}{\mathrm{Cn}}_i})}$

The finite impulse filters H _{NTF, FIR}(z):

$H_{\mathrm{STF},\mathrm{FIR}}\left(z\right)=\left(\frac{\underset{i=1}{\overset{P}{\mathrm{\Σ}}}{\mathrm{Cp}}_{P+1-i}{z}^{-(i-1)}}{\mathrm{Cop}+\underset{i=1}{\overset{P}{\mathrm{\Σ}}}{\mathrm{Cp}}_i}\right)-\left(\frac{\underset{i=1}{\overset{N}{\mathrm{\Σ}}}{\mathrm{Cn}}_{N+1-i}{z}^{-(i-1)}}{\mathrm{Con}+\underset{i=1}{\overset{N}{\mathrm{\Σ}}}{\mathrm{Cn}}_i}\right)$

Fig. 4 A is the frequency response H of finite impulse (IIR) filter of narrower frequency range _{STF, IIR}(z) and H _{NTF, IIR}(z).H _{STF, IIR}(z) can make the interior data signal of effective band not by filtering.H _{NTF, IIR}(z) can make the interior common-mode noise of effective band by filtering.

Fig. 4 B is the frequency response H of wireless pulses (FIR) filter of broad frequency range _{STF, FIR}(z) and H _{NTF, FIR}(z).H _{STF, FIR}(z) can make the interior data signal of effective band not by filtering.H _{NTF, FIR}(z) can make the interior effective filtering of common-mode noise of effective band.In addition, with the H of Fig. 4 A _{STF, IIR}(z) compare the H of Fig. 4 B _{STF, FIR}(z) frequency range is bigger.

Fig. 4 C and Fig. 4 D more show the usefulness of above-mentioned iir filter and FIR filter respectively with the filtering result of signal.The test signal of importing described filter comprises a differential wave of a certain characteristic frequency (for example 2MHz) in the effective band and a common mode signal that spreads all over a broadband (for example 0-300MHz).Filtering result shown in Fig. 4 C and Fig. 4 D shows that the response of this differential wave is good, is output to near-complete (shown in Sdiff), and this common-mode signal is then effectively constrained, especially the oppressive effect the most obvious (shown in Ncom) in the effective band.

The 300 couples of frequency response that synchronous input signal provided (HNTF of charge-domain filter, IIR (z), HNTF, FIR (z)) except the common-mode signal in the effective band there being apparent inhibition effect, the more effective even-order of filtered signal (even-order) harmonic wave and improve element (mismatch) problem that do not match.Unfavorable in-phase signal all can be by 300 filterings of charge-domain filter in input signal V1 and the V2.

Yet, observe Fig. 4 A, Fig. 4 B, can find the frequency response H of common-mode signal _{NTF, IIR}(z), H _{NTF, FIR}(z) unsatisfactory in the filter effect of non-effective band part.The present invention more discloses a kind of charge-domain filter superimposingtechnique, with effective head it off.Fig. 5 A is a kind of filter, wherein has two charge-domain filter 300_1 (having transduction device GM11 and GM21) and 300_2 (having transduction device GM12 and GM22) of superposition.The output of first order charge-domain filter 300_1 will be as the input of second level charge-domain filter 300_2.The frequency response of Fig. 5 B displayed map 5A filter.Frequency response H with reference to the common mode input _NTF, undesirable common-mode signal also can be by effective filtering at non-effective band 502.In addition, it is isostructural charge-domain filter that the next stage circuit of charge-domain filter serial connection does not limit, and also may be other circuit beyond the charge-domain filter.

Fig. 6 enumerates other execution mode of this case charge-domain filter, and wherein, phase splitter 602 can be realized by mixer.Phase splitter 602 is four first split phase signal I11, I12, I13 and I14 with the first input signal V1 phase-splitting, and is four second split phase signal I21, I22, I23 and I24 with the second input signal V2 phase-splitting.Compared to the first input signal V1, the above-mentioned first split phase signal I11 ... I14 has 0 °, 90 °, 180 °, 270 ° phase difference respectively.Compared to the second input signal V2, the above-mentioned second split phase signal I21 ... I24 has 0 °, 90 °, 180 °, 270 ° phase difference respectively.The first split phase signal I11 ... I14 is respectively by the first switched capacitor network 604_1 ... 604_4 receives.The second split phase signal I21 ... I24 is respectively by second switch capacitance network 606_1 ... 606_4 receives.Connection line 608 is responsible for first, second switched capacitor network 604_1 ... 604_4 and 606_1 ... the coupling access status of the output of 606_4 is to provide output signal OUT1 ... OUTK.

Only produce 0 °, 180 ° split phase signal compared to charge-domain filter 300 phase splitters 302,0 °, 90 °, 180 °, the 270 ° split phase signals that charge-domain filter 600 phase splitters 602 are produced can be applicable to image frequency to be suppressed above the circuit of (image rejection).

Fig. 7 is the another kind of execution mode of this case charge-domain filter, wherein adopts the time-interleaving technology.Compare with charge-domain filter 100, charge-domain filter 700 is different in the design of switched capacitor network.As shown in the figure, each the first/the second split phase signal I11 ... I1N and I21 ... I2N is only received by single switched capacitor network, but by receiving in turn in one group of (M) switched capacitor network.For example, the first split phase signal I11 is received in turn by the network in one group of first switched capacitor network 704_1, and this group first switched capacitor network 704_1 has the output that is coupled in together; The first split phase signal I1N is received in turn by the network in one group of first switched capacitor network 704_N, and this group first switched capacitor network 704_N has the output that is coupled in together; The second split phase signal I21 is received in turn by the network in one group of second switch capacitance network 706_1, and this group second switch capacitance network 706_1 has the output that is coupled in together; The second split phase signal I2N is received in turn by the network in one group of second switch capacitance network 706_N, and this group second switch capacitance network 706_N has the output that is coupled in together.All first/second switch capacitance network 704_1 ... 704_N, 706_1 ... the output of 706_N will more connect via connection line 708 distributions, to produce output signal OUT1 ... OUTK.

Compared to charge-domain filter 100, charge-domain filter 700 need not increase sampling frequency can provide finer filter response.

More than enumerate numerous embodiments and accompanying drawing and support this case summary of the invention.Yet above-mentioned execution mode is not to be used for limiting this case scope.Claim must be done to understand widely with the content of claim scope in detail.

Claims (15)

1. charge-domain filter comprises:

Phase splitter receives first input signal and second input signal, to produce about a plurality of first split phase signals of this first input signal and about a plurality of second split phase signals of this second input signal;

A plurality of first switched capacitor networks, corresponding one to one with described first split phase signal, have input separately and receive pairing above-mentioned first split phase signal and have output separately;

A plurality of second switch capacitance networks, corresponding one to one with described second split phase signal, have input separately and receive pairing above-mentioned second split phase signal and have output separately;

Connection line disposes the situation that couples of the above-mentioned output of the above-mentioned output of above-mentioned first switched capacitor network and above-mentioned second switch capacitance network, to produce a plurality of output signals.

2. charge-domain filter as claimed in claim 1, wherein, above-mentioned first split phase signal comprises first in-phase signal and first inversion signal of this first input signal relatively, and above-mentioned second split phase signal comprises second in-phase signal and second inversion signal of this second input signal relatively.

3. charge-domain filter as claimed in claim 2, wherein, this connection line couples the output of the pairing second switch capacitance network of this second inversion signal with the output of pairing first switched capacitor network of this first in-phase signal, and the output of pairing first switched capacitor network of this first inversion signal is coupled the output of the pairing second switch capacitance network of this second in-phase signal.

4. charge-domain filter as claimed in claim 3, wherein, described first split phase signal relatively this first input signal has the phase difference of 0 °, 90 °, 180 ° and 270 ° respectively, and described second split phase signal relatively this second input signal have the phase difference of 0 °, 90 °, 180 ° and 270 ° respectively.

5. charge-domain filter as claimed in claim 4, wherein, this connection line determines the above-mentioned output of the above-mentioned output of above-mentioned first switched capacitor network and above-mentioned second switch capacitance network to be coupled to the state of four nodes, to provide above-mentioned output signal in above-mentioned four nodes.

6. charge-domain filter as claimed in claim 1, wherein, this connection line comprises cabling and at least one electronic component or circuit, indirectly or directly connect the output of above-mentioned first and second switched-capacitor circuit.

7. filter comprises:

The multistage charge-domain filter of serial connection, wherein, charge-domain filters at different levels comprise:

Phase splitter receives first input signal and second input signal, to produce about a plurality of first split phase signals of this first input signal and about a plurality of second split phase signals of this second input signal;

A plurality of first switched capacitor networks, corresponding one to one with described first split phase signal, have input separately and receive pairing above-mentioned first split phase signal and have output separately;

A plurality of second switch capacitance networks, corresponding one to one with described second split phase signal, have input separately and receive pairing above-mentioned second split phase signal and have output separately;

Connection line disposes the situation that couples of the above-mentioned output of the above-mentioned output of above-mentioned first switched capacitor network and above-mentioned second switch capacitance network, to produce at least two input signals that output signal is the next stage circuit.

8. filter as claimed in claim 7, in charge-domain filters at different levels, above-mentioned first split phase signal comprises first in-phase signal and first inversion signal of this first input signal relatively, and above-mentioned second split phase signal comprises second in-phase signal and second inversion signal of this second input signal relatively.

9. filter as claimed in claim 8, in charge-domain filters at different levels, this connection line couples the output of the pairing second switch capacitance network of this second inversion signal with the output of pairing first switched capacitor network of this first in-phase signal, and the output of pairing first switched capacitor network of this first inversion signal is coupled the output of the pairing second switch capacitance network of this second in-phase signal.

10. filter as claimed in claim 7, in charge-domain filters at different levels, above-mentioned connection line comprises cabling and at least one electronic component or circuit, indirectly or directly connect the output of above-mentioned first and second switched-capacitor circuit.

11. a charge-domain filter comprises:

Phase splitter receives first input signal and second input signal, to produce about a plurality of first split phase signals of this first input signal and about a plurality of second split phase signals of this second input signal;

Many group first switched capacitor networks, each group is corresponding one to one with described first split phase signal, and above-mentioned first switched capacitor network has input separately and receives pairing above-mentioned first split phase signal and have output separately;

Many group second switch capacitance networks, each group is corresponding one to one with described second split phase signal, and above-mentioned second switch capacitance network has input separately and receives pairing above-mentioned second split phase signal and have output separately;

Connection line disposes the situation that couples of the above-mentioned output of the above-mentioned output of above-mentioned first switched capacitor network and above-mentioned second switch capacitance network, to produce a plurality of output signals.

12. charge-domain filter as claimed in claim 11, wherein, the output of first switched capacitor network on the same group is coupled in together, and the output of second switch capacitance network on the same group is coupled in together.

13. charge-domain filter as claimed in claim 12, wherein, above-mentioned first split phase signal comprises first in-phase signal and first inversion signal of this first input signal relatively, and above-mentioned second split phase signal comprises second in-phase signal and second inversion signal of this second input signal relatively.

14. charge-domain filter as claimed in claim 13, wherein, this connection line couples the output of this group second switch capacitance network of this second inversion signal correspondence with this output of organizing first switched capacitor network of this first in-phase signal correspondence, and this output of organizing first switched capacitor network of this first inversion signal correspondence is coupled the output of this group second switch capacitance network of this second in-phase signal correspondence.

15. charge-domain filter as claimed in claim 11, wherein, this connection line comprises cabling and at least one electronic component or circuit, indirectly or directly connect the output of above-mentioned first and second switched-capacitor circuit.

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