DE102018207546A1 - Electronic measuring circuit arrangement for generating a response signal to an excitation signal at an output of the electronic measuring circuit arrangement, electronic measuring device for detecting a capacitive measuring signal and method for detecting a capacitive measuring signal to an electronic measuring device - Google Patents

Abstract

The present invention provides an electronic measuring circuit arrangement (1) for generating a response signal (3) on an excitation signal (2; 2a; 2b) at an output (A) of the electronic measuring circuit arrangement (1), comprising a clock device (4) by means of which a temporal clocking (t) for the excitation signal (2) can be predetermined; an excitation device (5; 5a; 5b) which is connected to the clock device (4) and by means of which the excitation signal (2; 2a; 2b) can be generated according to the temporal clocking (t); at least one first and one second electronic measuring channel (MK1; MK2), which are connected to the excitation device (5; 5a; 5b) and which each comprise a capacitance bridge (KB), wherein the capacitance bridge (KB) comprises a first measuring capacitor (C1Ma; C1Mb ), a second measuring capacitor (C2Ma; C2Mb), a first reference capacitor (C1Ra; C1Rb) and a second reference capacitor (C2Ra; C2Rb), wherein the first measuring capacitor (C1Ma; C1Mb) and the second measuring capacitor (C2Ma; Capacitance are variable by an external influence and the first reference capacitor (C1Ra; C1Rb) and the second reference capacitor (C2Ra; C2Rb) have a constant capacitance, and wherein the first and second measuring channels (MK1; MK2) have a first and a second partial signal ( 3a, 3b) from the excitation signal (2), all sub-signals for forming the response signal (3) being superimposable at the output (A).

Description

The present invention relates to an electronic measuring circuit arrangement for generating a response signal to an excitation signal at an output of the electronic measuring circuit arrangement, to an electronic measuring device for detecting a capacitive measuring signal and to a method for detecting a capacitive measuring signal at an electronic measuring device.

State of the art

When sensor devices, a determination of a measurement signal is usually sought, which attracts as little interference, such as a low noise in the signal in the measurement with it. Particularly regarding the Internet of Things and mobile applications, sensors are required which have high accuracy and are energy-saving. Capacitive sensors are particularly well suited for such applications since the measuring principle itself does not require any current for measuring operation. Furthermore, it is possible to save energy by operating the sensors in a pulsed mode. In a pulsed operation with a pulsed voltage, such as with rectangular profiles, for reading the measuring capacity of the sensor, however, this broadband can be excited to mechanical vibrations, which can result in a settling noise on the measurement signal.

In the DE 10 2016 107 299 A1 For example, a measuring method, a measuring circuit and a measuring device are described, wherein a signal is determined by means of a random jitter on a scanning signal. A measuring method comprises generating a response signal in response to an excitation signal with a sensor. The method also includes generating a sampling clock signal in accordance with a pseudorandom jitter and sampling the response signal in accordance with the sampling clock signal to determine a plurality of digital samples. The method also includes combining the plurality of digital samples to form a measurement sample.

Disclosure of the invention

The present invention provides an electronic measuring circuit arrangement for generating a response signal to an excitation signal at an output of the electronic measuring circuit arrangement according to claim 1, an electronic measuring device for detecting a capacitive measuring signal according to claim 9 and a method for detecting a capacitive measuring signal to an electronic measuring device according to claim 11 ,

Preferred developments are subject of the dependent claims.

Advantages of the invention

The idea on which the present invention is based is to generate a time-delayed excitation of measuring channels in a measuring circuit arrangement, for example a sensor device, in its excitation signal, which is required for the measuring activity of the sensor device, in particular the measuring circuit arrangement. The time-offset excitation can reduce the signal noise of an output signal of the measuring circuit arrangement, for example the natural oscillation noise on the measuring signal of the latter.

According to the invention, the electronic measuring circuit arrangement for generating a response signal to an excitation signal at an output of the electronic measuring circuit arrangement comprises a clock device, by means of which a temporal clocking for the excitation signal can be predetermined; an excitation device which is connected to the clock device, and by means of which the excitation signal according to the temporal clocking can be generated. Furthermore, the measuring circuit arrangement comprises at least a first and a second electronic measuring channel, which are connected to the excitation device and which each comprise a capacitance bridge, wherein the capacitance bridge comprises a first measuring capacitor, a second measuring capacitor, a first reference capacitor and a second reference capacitor, wherein the first Measuring capacitors and the second measuring capacitor in the capacitance are variable by an external influence and the first reference capacitor and the second reference capacitor having a constant capacitance, and wherein the first and the second measuring channel generate a first and a second partial signal from the excitation signal, wherein all the partial signals for Forming the response signal are superimposed on the output.

The response signal advantageously comprises information about a state present and to be measured at the first measuring capacitor and at the second measuring capacitor, for example a pressure prevailing there, which can be deduced by current capacitances (changes in the capacitance) of the measuring capacitors relative to the reference capacitors. The measurement is carried out by a control of the measuring capacitors with the excitation signal, wherein the first and the second measuring channel respectively generate a response signal as partial signals. By a time-variable excitation signal, a transient noise can be generated in each of the measurement channels. The entire transient noise of the whole Measuring circuit arrangement is advantageously reduced by a superimposition of the sub-signals, wherein the mechanical vibration-related dynamic parts of the sub-signals destructively cancel, while adding up the static parts of the sub-signals constructively. By such a reduction of the noise on the response signal, a higher measurement resolution, in particular with MEMS sensors, can be achieved.

In this case, it is advantageously possible that the measuring capacitors and / or the reference capacitors in each case or occasionally comprise only one capacitor or a plurality of capacitors or capacitors connected in parallel.

The two or more measuring channels can be advantageously constructed the same, or have different components or Verschaltungsarten. The excitation device transmits the excitation signal predetermined in terms of shape and duration as well as in characteristic time scales and oscillation behavior / frequencies (variation behavior, temporal clocking) to the measurement channels by the clock generator device. In this case, all measuring channels can be controlled with excitation signals offset in time but otherwise identical or with different excitation signals.

According to a preferred embodiment of the measuring circuit arrangement, each capacitance bridge comprises a first bridge section, in which the first measuring capacitor and the first reference capacitor are arranged; and a second bridge portion in which the second measurement capacitor and the second reference capacitor are arranged.

According to a preferred embodiment of the measuring circuit arrangement, the first bridge section and the second bridge section comprise a common first input node and a common second input node, in which these are connected.

The bridge sections can, within a measurement channel or a capacity bridge, seen from the first common input node toward the second common input node, in which the two bridge sections are interconnected, comprise the same order of the measurement capacitor and reference capacitor arrangement or a different order. The excitation device can advantageously be connected both to the first and to the second common input node and to drive the capacitance bridge via this input node. Within a bridge section, a first or second sub-signal can be taken between the measuring capacitor and the reference capacitor and fed to the output and superimposed with the sub-signals from the other bridge section and from the further measuring channel.

According to a preferred embodiment of the measuring circuit arrangement, the first and the second measuring capacitor are pressure-sensitive, wherein a capacitance of the first and the second measuring capacitor varies more strongly to a change of an external influence than a capacitance of the first and the second reference capacitor.

The external influence can be a pressure change.

The greater variation can advantageously ensure that the measuring capacitors are those components by means of which the pressure is measured.

According to a preferred embodiment of the measuring circuit arrangement, the capacitance bridge comprises a Wheatstone bridge.

According to a preferred embodiment of the measuring circuit arrangement, the measuring channels all have an equal capacitance and the measuring capacitors have the same mechanical natural frequency.

According to a preferred embodiment of the measurement circuit arrangement, the excitation device comprises a first excitation device and a second excitation device, the first excitation device being connected to the first electronic measurement channel and the second excitation device being connected to the second electronic measurement channel and being drivable by the latter with the excitation signal and a time-delayed excitation signal ,

The two excitation devices can be advantageously already controlled by the clock device with different clock signals and generate time-shifted excitation signals on this basis.

According to a preferred embodiment of the measuring circuit arrangement, this comprises a time delay device for the excitation signal, by means of which a time-delayed excitation signal can be generated, wherein the first electronic measuring channel or the second electronic measuring channel is connected to the delay device.

The delay device may be interconnected within the measuring channel or be connected upstream of this at an input node, such that advantageously only this one measuring channel with the time-delayed excitation signal is activated. The delay device may be, for example, an RC element.

According to the invention, the electronic measuring device for detecting a capacitive measuring signal comprises an electronic measuring circuit arrangement according to the invention; a signal amplifier means connected to the output of the measurement circuit and adapted to receive the response signal from the output; an analog-to-digital converter device, which is connected downstream of the signal amplifier device; and a filter device configured to receive a signal from the analog-to-digital converter device and configured to generate a digital output signal as a capacitive measurement signal.

The capacitive measuring signal can advantageously already be output in such a form that it can be further processed or at least read out by a digital device, for example a digital circuit, a control device or a computer.

Advantageously, the signal amplifier means may sample the response signal at a sampling frequency, and the filtering means may average the signal over a plurality of pulses.

According to a preferred embodiment of the electronic measuring device, this is designed as a pressure sensor, microphone, acceleration sensor or yaw rate sensor.

According to the invention, in the method for detecting a capacitive measuring signal at an electronic measuring device takes place in a method step S1 a provision of an electronic measuring device according to the invention. In a further process step S2 there is a predetermining of a time clocking on a clock generator device and generating an excitation signal with an excitation device based on the time clocking. In one process step S3 a driving of at least a first and a second electronic measuring channel with the excitation signal, each comprising a capacitance bridge, wherein the capacitance bridge comprises a first measuring capacitor, a second measuring capacitor, a first reference capacitor and a second reference capacitor, wherein the first measuring capacitor and the second measuring capacitor in whose capacity are variable by an external influence and the first reference capacitor and the second reference capacitor have a constant capacitance, and wherein the first measuring channel, a first partial signal and the second measuring channel generate a second partial signal from the excitation signal. In a further process step S4 there is a time delay of the excitation signal at one of the measuring channels with respect to a remaining one of the measuring channels; and in one process step S5 a superposition of the sub-signals to a response signal at an output. In a further process step S6 there is a driving of a signal amplifier device, an analog-digital converter device, and a filter device, with the response signal and generating a digital output signal as a capacitive measurement signal from the response signal.

The method is advantageously characterized by the features and advantages described in connection with the measuring circuit arrangement and the measuring device, and vice versa.

The excitation signal is applied after a time offset, advantageously several times offset with respect to a plurality of measurement channels, to a plurality of measurement channels and then superimposed their answers as partial signals to a common response signal. In other words, a first measurement channel can be driven with an undelayed excitation signal, and a second measurement channel can be driven with an excitation signal, which is shifted by a constant time period but otherwise identical, or different excitation signal. A third measuring channel can in turn be driven by the same constant time period but otherwise identical excitation signal, or different excitation signal, and also other measuring channels can be shifted by integral multiples of the constant time period.

Furthermore, with regard to the measuring capacitors and reference capacitors as well as further components in the second measuring channel, as well as in other subsequently controlled measuring channels, advantageously the size of the measuring capacitors and / or reference capacitors and / or further components can be adjusted in such a way, advantageously from the outset, that attenuation of each earlier controlled measuring channels / measuring channels, or only the immediately previously controlled measuring channel at the or the later controlled (n) measuring channel / measuring channels, is compensated. Alternatively, the amplitude of the time-shifted second excitation signal relative to the first excitation signal can also be adapted in order to compensate for an attenuation of the oscillation triggered by the first excitation signal.

Concerning the measuring capacitors, the property and size of their vibrating membrane (electrode) is advantageously known, from where the resonance vibration behavior can be derived advantageously and the remaining components for achieving a destructive superposition for the natural vibration noise can advantageously be determined and carried out or provided. Due to the advantageously known sizes and parameters of the measuring capacitors can therefore be easily deduced, for example after comparison with reference capacitors, on the pressure at the measuring capacitor.

According to a preferred embodiment of the method produced in the method step S2 the clock means having a first timing and a time delayed second timing, wherein the first timing is passed to a first excitation device and the second timing to a second excitation device, wherein the first excitation device with the first electronic measurement channel and the second excitation device with the second electronic measuring channel is connected and in the process step S4 the excitation signal is transmitted to the first electronic measuring channel and a time-delayed excitation signal is transmitted to the second electronic measuring channel.

According to a preferred embodiment of the method, the first time clock and the second time clock are time-shifted by a constant time difference.

The time difference by which the clocks, advantageously this can be done correspondingly for more than two clocks, are time offset, is advantageously carried out equidistantly per measuring channel. In this case, equidistantly means constant time segments within at least one period of a natural oscillation. Advantageously, for the possible equidistant time offset, approximately a quantitative value dt (quant) is approximately equal to dt (quant) ~ m * tres + tres / n, where tres corresponds to the time duration which the measuring circuit arrangement (all n measuring channels) generates to generate all the excitation signals or the response signal needed. This results in a set of possible values for the time offset dt as
dt = {dtmin; dtmin + 1 * dt (quant); ...; dtmax = dtmin + (n-1) × dt (quant)} with integers m and n, where m must be chosen such that
dtmax << t (pulse length). For example, for m = 0 and n = 5, dt (quant) ~ tres / 5 increases; for dtmin = 0, dt = {0; 1 × tres / 5; 2 × tres / 5; 3 × tres / 5; 4 × tres / 5}. The method is robust as long as for a deviation δ of dt (quant): $$\left|\mathrm{\delta }\right|<<\text{dtres /}2{\text{n}}^2,$$

The read-out signal is detected after the excitation of all measuring channels, ie after dtmax.

Such an equal distribution of excitation signals, advantageously of pulses of the excitation signal, over a phase space advantageously causes a destructive superposition of the natural oscillations of the measurement channels in the response signal, resulting in a much smoother response signal with reduced intrinsic vibration noise.

According to a preferred embodiment of the method, the time delay takes place in the method step S4 by means of a delay device which is connected in the first electronic measuring channel or in the second electronic measuring channel.

By means of a pulsed signal (readout method), a sensor device, in particular a capacitive sensor device, can be improved in its energy-saving efficiency. By a rectangular pulsed excitation signal, the measuring circuit and its components (untargeted) can be excited to mechanical vibrations. In a capacitor, such as the measuring capacitor, caused by the pulsed voltage electrical potential differences between the two electrodes, resulting in a relative attractive force, whereby natural mechanical vibration modes are excited. In this way, a small dynamic noise component is superimposed on the actual static measurement signal. However, this effect can also occur with other time-variable excitation signal patterns. For example, a fundamental mode of the mechanical natural oscillations can lead to an electrically measurable oscillation behavior of the measuring capacitors, in particular of the measuring capacitors, resulting in a vibration behavior (noise) of a response signal at the output. A decay time of the measuring circuit arrangement, advantageously the capacitance bridge as a mechanically oscillating system, is determined by its damping behavior or by its quality. In the case of capacitive sensor devices, such mechanical oscillating components advantageously comprise a low mechanical vibration quality with respect to the excitation signal. However, pressure sensors are usually high-quality systems.

Further features and advantages of embodiments of the invention will become apparent from the following description with reference to the accompanying drawings.

list of figures

The present invention will be explained in more detail with reference to the exemplary embodiments indicated in the schematic figures of the drawing.

• 1 eine schematische Darstellung einer elektronischen Messvorrichtung mit einer elektronischen Messschaltungsanordnung gemäß eines Ausführungsbeispiels der vorliegenden Erfindung;
• 2 eine schematische Darstellung einer elektronischen Messvorrichtung mit einer elektronischen Messschaltungsanordnung gemäß eines weiteren Ausführungsbeispiels der vorliegenden Erfindung; und
• 3 eine schematische Darstellung einer Abfolge von Verfahrensschritten gemäß eines Ausführungsbeispiels der vorliegenden Erfindung.

Show it:

• 1 a schematic representation of an electronic measuring device with an electronic measuring circuit arrangement according to an embodiment of the present invention;
• 2 a schematic representation of an electronic measuring device with an electronic measuring circuit arrangement according to another embodiment of the present invention; and
• 3 a schematic representation of a sequence of method steps according to an embodiment of the present invention.

In the figures, like reference numerals designate the same or functionally identical elements.

1 shows a schematic representation of an electronic measuring device with an electronic measuring circuit arrangement according to an embodiment of the present invention.

The electronic measuring device 10 for detecting a capacitive measuring signal S includes electronic measurement circuitry 1 wherein a signal amplifier means 7 with the exit A the measuring circuit arrangement 1 is interconnected and that consists of several sub-signals 3a and 3b superimposed response signal 3 from the measurement circuitry 1 can receive. From the exit A away, the signal amplifier device 7 below an analog-to-digital converter device 8th be downstream, which in turn a filter device 9 can be connected downstream, which from the response signal 3 a capacitive measuring signal S as a digital output signal of the measuring device 10 can generate. The capacitive measuring signal S may itself also consist of at least two partial signals, each of which is based on the superimposed signals of the first bridge sections KB11 and KB21 come from a superimposed total signal. In the electrical measuring circuit arrangement 1 generates a clock device 4 a temporal clocking t , which a first temporal clocking t1 and a second timing delayed by a constant time difference dt t2 may include. With the clock device 4 may be a first excitation device 5a and a second excitation means 5b be connected, wherein a clock signal with the first clock t1 to the first excitation device 5a is forwarded and a clock signal with the second clocking t2 to the second excitation device 5b is forwarded. The first excitation device 5a generated based on the first timing t1 , a first excitation signal 2a and the second excitation means 5b generated based on the second timing t2 , a second excitation signal 2 B , The first excitation device 5a generates an excitation signal 2a , For example, a rectangular readout voltage pulse, with which a first electronic measuring channel MK1 is controlled. The first electronic measuring channel MK1 may have a common first input node X1 in which a first bridge section KB11 and a second bridge section KB12 of the first measuring channel MK1 are interconnected. In this case, the first measuring channel comprises MK1 a capacity bridge KB1 with the first and second bridge sections KB11 and KB12 , The capacity bridge KB1 can still have a second common input node Y1 include, in which the two bridge sections KB11 and KB12 interconnected with each other. Like the first entrance node X1 is also the second entrance node Y1 with the first excitation device 5a connects and receives the excitation signal 2a , The first bridge section KB11 includes a first measuring capacitor C1Ma and a first reference capacitor C1Ra , which in the first bridge section KB11 connected in series with each other. The second bridge section KB11 includes a second measuring capacitor C2Ma and a second reference capacitor C2Ra , which in the second bridge section KB12 are connected in series with each other, but with respect to the two input nodes X1 and Y1 in reverse order than the capacitors in the first bridge section KB11 , In each of the bridge sections, the signal between the measuring capacitor and the reference capacitor becomes the output A led out. This results in the first measuring channel MK1 a signal path for a sub-signal 3a from the first and the second bridge section.

The two partial signals 3a Advantageous are the bridge voltage taps of the Wheatstone bridge of the first measuring channel. A measuring channel advantageously corresponds to a Wheatstone bridge. Advantageously, the sub-signals of the two measuring channels / Wheatstone bridges are superimposed 3a and 3b , Due to the time-delayed excitation, the oscillation components of the signal are advantageously destructively superimposed, while the static signal components advantageously add constructively, which can result in a better signal-to-noise ratio.

The delayed excitation signal 2 B is from the second exciter 5b to the second measuring channel MK2 forwarded. The temporal pattern and amplitude values can be the excitation signal 2a match, but around dt be delayed. The second measuring channel MK2 receives the delayed excitation signal 2 B at a first entrance node X2 and at a second input node Y2 , in each of which a first bridge section KB21 and a second bridge section KB22 the capacity bridge of the second measuring channel MK2 can be interconnected. The first bridge section KB21 and the second bridge section KB22 in the second measuring channel MK2 are advantageously analogous to the bridge sections of the first measuring channel MK1 built up, but could also be different. The second measuring channel accordingly comprises a first measuring capacitor C1Mb and a first reference capacitor C1Rb and a second measuring capacitor C2MB and a second reference capacitor c2RB , It would also be possible for the measurement circuitry 1 (n-2) comprises further measuring channels, which are constructed analogously to the first and the second measuring channel and receive an excitation signal to corresponding input nodes, which by a constant time difference (n-1) x dt (n as an integer and ordinal number of the measuring channel) is delayed. Between the measuring capacitors and the reference capacitors can from the bridge sections of the second, and if any other measuring channel, a partial signal 3b the response signal 3 be led out, which then with the sub-signals of the other measurement channels ( MK1 . MK2 , ..., MKn ) to a response signal 3 at the exit A can be superimposed. In the process, these sub-signals can have properties such that, in the case of an overlay, the intrinsic vibration noise of the components in the measurement channels is destructively superimposed and significantly reduced. The superimposed response signal 3 Therefore, there is less noise and a more accurate signal component of the pressure applied to the measuring capacitors pressure effect, which triggers a change in capacitance of the measuring capacitors.

2 shows a schematic representation of an electronic measuring device with an electronic measuring circuit arrangement according to another embodiment of the present invention.

The arrangement of 2 includes, similar to the arrangement of the measuring circuit arrangement 1 from the 1 , a first electronic measuring channel MK1 and a second electronic measuring channel MK2 , with the difference that not only the bridge sections of a measurement channel in a first common input node X1 and in a common second input node Y1 are interconnected, but also both measuring channels MK1 and MK2 , Because the measurement circuitry 1 from the 2 via only one excitation device 5 which may be the excitation signal 2a generated, received at the entrance node X1 and Y1 both measuring channels the same excitation signal 2a , The clock device 4 generates advantageous only a temporal clocking t. The excitation signal 2a can by a delay device 12 in a delayed excitation signal 2 B converted, in particular, only be postponed. The delay device 12 can be immediately after one of the input nodes X1 or Y1 , for example after the first common input node X1 , and before the splitting of the second measuring channel into the two bridge sections, be arranged so that both bridge sections of the second measuring channel MK2 a delayed excitation signal 2 B receive. From the two measuring channels, the partial signals 3a and 3b in the same way to the exit A be guided, as in the arrangement of the 1 the case is. Similarly, other measurement channels could be connected to the first measurement channel MK1 in the entrance node X1 and Y1 be connected in parallel, and own delay devices 12 and further sub-signals for superposition at the output A produce.

3 shows a schematic representation of a sequence of method steps according to an embodiment of the present invention.

In the method for detecting a capacitive measuring signal on an electronic measuring device, the method steps are advantageously carried out in the order given S1 to S6 , In the process step S1 there is provided an electronic measuring device according to the invention. In a further process step S2 there is a predetermining of a timing of a clock device and generating an excitation signal with an excitation device based on the timing and in the method step S3 a driving of at least a first and a second electronic measuring channel with the excitation signal, each comprising a capacitance bridge, wherein the capacitance bridge comprises a first measuring capacitor, a second measuring capacitor, a first reference capacitor and a second reference capacitor, wherein the first measuring capacitor and the second measuring capacitor in whose capacitance is variable by an external influence and the first reference capacitor and the second reference capacitor have a constant capacitance, and wherein the first measuring channel generates a first partial signal and the second measuring channel generates a second partial signal from the excitation signal. In one process step S4 there is a time delay of the excitation signal at one of the measuring channels with respect to a remaining one of the measuring channels; and in one process step S5 a superposition of the sub-signals to a response signal at an output. In one process step S6 there is a driving of a signal amplifier device, an analog-digital converter device, and a filter device, with the response signal and generating a digital output signal as a capacitive measurement signal from the response signal.

Although the present invention has been fully described above with reference to the preferred embodiment, it is not limited thereto but may be modified in a variety of manners.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102016107299 A1 [0003]

Claims (14)

Electronic measuring circuit arrangement (1) for generating a response signal (3) to an excitation signal (2; 2a; 2b) at an output (A) of the electronic measuring circuit arrangement (1) - A clock means (4) by means of which a temporal clocking (t) for the excitation signal (2) can be predetermined; - An excitation means (5; 5a; 5b) which is connected to the clock means (4), and by means of which the excitation signal (2; 2a; 2b) according to the temporal clocking (t) can be generated; - At least a first and a second electronic measuring channel (MK1; MK2), which are connected to the excitation means (5; 5a; 5b) and which each comprise a capacitance bridge (KB), wherein the capacitance bridge (KB) a first measuring capacitor (C1Ma; C1Mb), a second measuring capacitor (C2Ma; C2Mb), a first reference capacitor (C1Ra; C1Rb) and a second reference capacitor (C2Ra; C2Rb), the first measuring capacitor (C1Ma; C1Mb) and the second measuring capacitor (C2Ma; C2Mb) in whose capacitance is variable by an external influence and the first reference capacitor (C1Ra; C1Rb) and the second reference capacitor (C2Ra; C2Rb) have a constant capacitance, and wherein the first and second measuring channels (MK1; MK2) comprise a first and a second partial signal (3a; 3b) from the excitation signal (2) generate, wherein all the sub-signals for forming the response signal (3) at the output (A) are superimposed. Electronic measuring circuit arrangement (1) according to Claim 1 in which each capacity bridge (KB1; KB2; ...; KBn) comprises a first bridge section (KB11; KB21; ...; KBn1) in which the first measurement capacitor (C1Ma; C1Mb) and the first reference capacitor (C1Ra; C1Rb) are arranged; and - a second bridge section (KB12; KB22; ...; KBn2) in which the second measuring capacitor (C2Ma; C2Mb) and the second reference capacitor (C2Ra; C2Rb) are arranged. Electronic measuring circuit arrangement (1) according to Claim 2 wherein the first bridge section (KB11; KB21; ...; KBn1) and the second bridge section (KB12; KB22; ...; KBn2) have a common first input node (X1; X2; ...; Xn) and a common second one Include input nodes (Y1; Y2; ...; Yn) in which they are connected. Electronic measuring circuit arrangement (1) according to one of Claims 1 to 3 in which the first and second measuring capacitors (C1Ma; C1Mb; C2Ma; C2Mb) are pressure-sensitive, wherein a capacitance of the first and second measuring capacitors (C1Ma; C1Mb; C2Ma; C2Mb) varies more than a capacitance to a change of an external influence the first and second reference capacitors (C1Ra; C1Rb; C2Ra; C2Rb). Electronic measuring circuit arrangement (1) according to one of Claims 1 to 4 in which the capacity bridge (KB) comprises a Wheatstone bridge. Electronic measuring circuit arrangement (1) according to one of Claims 1 to 5 , in which the measuring channels all have an equal capacitance and the measuring capacitors have a same mechanical natural frequency. Electronic measuring circuit arrangement (1) according to one of Claims 1 to 6 in which the excitation device (5) comprises a first excitation device (5a) and a second excitation device (5b), wherein the first excitation device (5a) with the first electronic measurement channel (MK1) and the second excitation device (5b) with the second electronic measurement channel (MK2) is connected and of these with the excitation signal (2a) and a delayed excitation signal (2b) are controllable. Electronic measuring circuit arrangement (1) according to one of Claims 1 to 6 , which comprises a time delay device (12) for the excitation signal (2a, 2b), by means of which a time-delayed excitation signal (2b) can be generated, wherein the first electronic measuring channel (MK1) or the second electronic measuring channel (MK2) with the delay device ( 12) is connected. Electronic measuring device (10) for detecting a capacitive measuring signal (S), comprising - an electronic measuring circuit arrangement (1) according to one of Claims 1 to 8th ; - A signal amplifier means (7) which is connected to the output (A) of the measuring circuit (1) and which is adapted to receive the response signal (3) from the output (A); - An analog-to-digital converter means (8), which is the signal amplifier means (7) connected downstream; and - a filter device (9), which is adapted to receive a signal of the analog-to-digital converter device (8), and which is adapted to generate a digital output signal as a capacitive measurement signal (S). Electronic measuring device (10) after Claim 9 , which is designed as a pressure sensor, microphone, acceleration sensor or rotation rate sensor. Method for detecting a capacitive measuring signal (S) at an electronic measuring device (10), comprising the steps: S1) providing an electronic measuring device (10) according to one of the Claims 9 or 10 ; S2) predetermining a timing (t) at a timing device (4) and generating an excitation signal (2a; 2b) with an excitation device (5; 5a; 5b) based on the timing (t); S3) driving at least one first and one second electronic measuring channel (MK1, MK2) with the excitation signal (2a, 2b), each comprising a capacitance bridge (KB), wherein the capacitance bridge (KB) comprises a first measuring capacitor (C1Ma, C1Mb), a second measuring capacitor (C2Ma; C2Mb), a first reference capacitor (C1Ra; C1Rb) and a second reference capacitor (C2Ra; C2Rb), wherein the first measuring capacitor (C1Ma; C1Mb) and the second measuring capacitor (C2Ma; C2Mb) in their capacitance an external influence is variable and the first reference capacitor (C1Ra; C1Rb) and the second reference capacitor (C2Ra; C2Rb) have a constant capacitance, and wherein the first measuring channel (MK1) includes a first sub-signal (3a) and the second measuring channel (MK2) second partial signal (3b) is generated from the excitation signal (2a; 2b); S4) temporally delaying the excitation signal (2a) at one of the measuring channels (MK1, MK2) with respect to a remaining one of the measuring channels (MK1, MK2); S5) superimposing the partial signals to a response signal (3) at an output (A); and S6) driving a signal amplifier device (7), an analog-to-digital converter device (8), and a filter device (9) with the response signal (3) and generating a digital output signal as a capacitive measurement signal (S) from the response signal (3). , Method according to Claim 11 in which, in method step S2, the clock device (4) generates a first time clock (t1) and a time-offset second time clock (t2), wherein the first time clock (t1) to a first excitation device (5a) and the second time clock (t2) is forwarded to a second excitation device (5b), wherein the first excitation device (5a) is connected to the first electronic measurement channel (MK1) and the second excitation device (5b) is connected to the second electronic measurement channel (MK2) and in process step S4 the first electronic measuring channel (MK1) the excitation signal (2a) and to the second electronic measuring channel (MK2) a delayed excitation signal (2b) is passed. Method according to Claim 12 in which the first time clock (t1) and the second time clock (t2) are time-shifted by a constant time difference (dt). Method according to Claim 11 in which the time delay in method step S4 takes place by means of a delay device (12) which is connected in the first electronic measuring channel (MK1) or in the second electronic measuring channel (MK2).

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