WO2003065058A1 - Schaltkreis-anordnung, redox-recycling-sensor, sensor-anordnung und verfahren zum verarbeiten eines über eine sensor-elektrode bereitgestellten stromsignals - Google Patents
Schaltkreis-anordnung, redox-recycling-sensor, sensor-anordnung und verfahren zum verarbeiten eines über eine sensor-elektrode bereitgestellten stromsignals Download PDFInfo
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- WO2003065058A1 WO2003065058A1 PCT/DE2003/000122 DE0300122W WO03065058A1 WO 2003065058 A1 WO2003065058 A1 WO 2003065058A1 DE 0300122 W DE0300122 W DE 0300122W WO 03065058 A1 WO03065058 A1 WO 03065058A1
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- 238000000034 method Methods 0.000 title claims abstract description 34
- 238000004064 recycling Methods 0.000 title claims abstract description 22
- 238000012545 processing Methods 0.000 title claims abstract description 17
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- 230000001105 regulatory effect Effects 0.000 claims description 3
- 238000005259 measurement Methods 0.000 description 63
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- 239000003298 DNA probe Substances 0.000 description 21
- 108020004414 DNA Proteins 0.000 description 20
- 108020003215 DNA Probes Proteins 0.000 description 19
- 230000008569 process Effects 0.000 description 12
- 102000004190 Enzymes Human genes 0.000 description 11
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- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 description 2
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Classifications
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
- G01N27/26—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating electrochemical variables; by using electrolysis or electrophoresis
- G01N27/28—Electrolytic cell components
- G01N27/30—Electrodes, e.g. test electrodes; Half-cells
- G01N27/327—Biochemical electrodes, e.g. electrical or mechanical details for in vitro measurements
- G01N27/3275—Sensing specific biomolecules, e.g. nucleic acid strands, based on an electrode surface reaction
- G01N27/3277—Sensing specific biomolecules, e.g. nucleic acid strands, based on an electrode surface reaction being a redox reaction, e.g. detection by cyclic voltammetry
Definitions
- the invention relates to a circuit arrangement, a redox recycling sensor, a sensor arrangement and a method for processing a current signal provided via a sensor electrode
- FIG. 2A shows a biosensor chip as described in [1].
- the sensor 200 has two electrodes 201, 202 made of gold, which are embedded in an insulator layer 203 made of electrically insulating material. Electrode connections 204, 205 are connected to the electrodes 201, 202, by means of which the electronic potential applied to the electrode 201, 202 can be supplied.
- the electrodes 201, 202 are designed as planar electrodes.
- DNA probe molecules 206 also referred to as capture molecules
- the immobilization takes place according to the gold-sulfur coupling.
- the analyte to be examined for example an electrolyte 207, is applied to the electrodes 201, 202.
- the electrolyte 207 contains DNA strands 208 with a base sequence that is complementary to the sequence of the DNA probe molecules 206, that is to say that the key molecules sterically fit the key-lock principle, these DNA strands 203 also hybridize the DNA probe molecules 206 (see FIG. 2B)
- Hybridization of a DIIA probe molecule 206 and a DMA strand 203 fmdec only takes place if the sequences of the respective DNA probe molecule and the corresponding DriA strand 203 are complementary to one another. If this is not the case If so, no hybridization takes place.
- a DNA probe molecule of a given sequence is only able to bind to a particular one, namely the DNA strand with a complementary sequence, ie to hybridize with it, resulting in the high degree of selectivity of sensor 200 results
- the value of the impedance between the electrodes 201 and 202 changes, as can be seen from FIG. 2B.
- This changed impedance is achieved by applying a suitable electrical voltage to the electrode connections 204, 205 and by detecting the resulting current detected
- the capacitive component of the impedance between the electrodes 201, 202 decreases. This is due to the fact that both the DNA probe molecules 206 and the DNA strand 208, which may hybridize with the DNA probe molecules 206, do not electrically are conductive and thus vividly partially shield the respective electrodes 201, 202 electrically.
- FIG. 3A The cross-sectional view along the section line II 'from FIG. 3A is shown in FIG. 3B.
- the dimension of the electrodes and the distances between the electrodes are in the order of magnitude of the length of the molecules to be detected, ie the DMA strand 208, or less, for example 200nm and below
- FIG. 4A shows a biosensor 400 with a first electrode 401 and a second electrode 402, which are applied on an insulator layer 403.
- a holding area 404 is applied on the first electrode 401 as gold.
- the holding area 404 serves for immobilizing DNA probes olekulen 405 on the first electrode 401 No such holding area is provided on the second electrode 402
- the biosensor 400 is to be used to detect DNA strand 407 with a sequence that is complementary to the sequence of the immobilized DNA probe molecules 405, the sensor 400 is brought into contact with a solution to be examined, for example an electrolyte 406, in such a way that DNA strand 407 possibly contained in the solution 406 to be examined can hybridize with the complementary sequence to the sequence of the DNA probe molecules 405.
- a solution to be examined for example an electrolyte 406
- Fig. B shows the case in which the DNA strand 407 to be detected is contained in the solution 406 to be examined and is hybridized with the DNA probes olekulen 405
- the DNA strands 407 in the solution to be examined are labeled with an enzyme 408, with which it is possible to split molecules described below into electrically charged partial molecules.
- an enzyme 408 with which it is possible to split molecules described below into electrically charged partial molecules.
- DNA probe molecules 405 is provided than DNA strand 407 to be determined contained in the solution 406 to be examined
- the biosensor 400 is rinsed, whereby the non-hybridized DNA strands are removed and the biosensor chip 400 is cleaned of the solution 406 to be examined.
- the rinsing solution used for rinsing or another solution supplied in a further phase becomes an electrically uncharged substance added, which contains molecules which can be cleaved by means of the enzyme 408 on the hybridized DNA strands 407, into a first sub-molecule 410 with a negative electrical charge and into a second molecule with a positive electrical charge
- the negatively charged first partial molecules 410 are drawn to the positively charged first electrode 401, which is indicated by the arrow 411 in FIG. 4C.
- the negatively charged first partial molecules 410 are attached to the electrode 401 has positive electrical potential, is oxidized and is drawn as oxidized sub-molecules 413 to the negatively charged second electrode 402, where they are reduced again.
- the reduced sub-molecules 414 in turn migrate to the positively charged first electrode 401. In this way an electrical circuit current is generated which is proportional to the number of charge carriers generated in each case by means of the enzymes 406
- FIG. 5 shows the function of the electrical current 501 m as a function of time 502.
- the resulting course 503 has an offset current I 0 £ f ⁇ -. 504, which is independent of the time profile.
- the offset current l o. Ss- 504 is generated on the basis of poor idealities of the biosensor 400.
- a major cause of the "offset current I : _s * - is that the covering of the first electrode 401 with the DNA probe molecules 405 is not ideal, ie it is not completely tight.
- the incomplete coverage leads to parasitic current paths between the first electrode 401 and the solution 406 to be examined, which also have ohmic components, among other things.
- the covering of the first electrode 401 with the DNA probe molecules 405 should not be complete so that the electrically charged partial molecules, i.e. the negatively charged first partial molecules 410 can reach the first electrode 401 due to an electrical force.
- the covering of the first electrode 401 with DNA probe molecules 405 should be sufficiently dense.
- both electrodes 401, 402 should always provide a sufficiently large amount of space for the O ⁇ dations- / Redkt ⁇ ons process in the context of the redox recycling process.
- Macromolecular biomolecules are, for example
- the first molecules and the second molecules are ligands, for example active substances with a possible one
- Binding activa which the proteins to be detected or Bind peptides to the respective electrode on which the corresponding ligands are arranged
- Suitable ligands are, for example, enzyme agonists, pharmaceuticals, sugar or antibodies or any other molecule which has the ability to specifically bind proteins or peptides.
- DNA strands of a given sequence are used as macromolecular biomolecules, which are to be detected by the biosensor, then DNA strands of a given sequence with DNA probe molecules with the sequence complementary to the sequence of the DNA strand can be used as molecules on the first electrode to be hybridized.
- a probe molecule (also called a catcher molecule) is to be understood as a ligand or a DNA probe molecule
- the value m dl / dt introduced above, which corresponds to the slope of the straight line 503 from FIG. 5, is proportional to the electrode area of the electrodes used to detect the measurement current.
- the value m is therefore proportional to the longitudinal extension of the electrodes used, for example in the case of the first electrode 201 and the second electrode 202 proportional to their length perpendicular to the plane of the drawing in FIGS. 2A and 2B. If several electrodes are connected in parallel, for example in the known one
- the value of the A. finite the measurement current may be referred to narnik Symposium on a wide range of values due to different influences, wherein the detectable by a sensor Stro -3ere ⁇ ch as D / • Frequently is more desirable dynamic range of a current intensity range of five decades called causes for the strong fluctuations can also be biochemical boundary conditions in addition to the sensor geometry. It is thus possible for the macromolecular biomolecules of different types to be detected to have very different value ranges for the resulting measurement signal, ie. in particular cause the measurement current and its change over time, which in turn leads to an expansion of the required entire dynamic range with corresponding requirements for a given electrode configuration with the following standardized measurement electronics
- the requirements for the large dynamic range of such a circuit mean that the measuring electronics are designed to be expensive and complicated in order to work with sufficient accuracy and reliability in the required dynamic range.
- the offset current IoF tso i is often much larger than the change over time of the measurement current m over the entire measurement period.
- a very small time-dependent change must be measured with high accuracy within a large signal. This places very high demands on the measuring instruments used, which makes the acquisition of the measuring current complex, complicated and expensive. This fact also counteracts the desired miniaturization of sensor arrangements.
- Small signal currents such as those that occur at a sensor, can be raised to a level with the aid of amplifier circuits, which allows the signal current to be forwarded, for example, to an external device or an internal quantification
- ADC analog-digital converter
- the ADC should have a correspondingly high resolution and a sufficiently high signal-to-noise ratio.
- the integration of such an analog-to-digital converter in the immediate vicinity of a sensor electrode also represents a high technological challenge, the corresponding process control is complex and expensive. Furthermore, it is extremely difficult to achieve a sufficiently high signal-to-noise ratio in the sensor
- the invention is based on the problem of creating a robust circuit arrangement with improved detection sensitivity for electrical currents which are very weakly variable over time
- a circuit arrangement is provided, the sensor electrode, a control circuit which is coupled to the sensor electrode via an input and a current source which is coupled via its control input to a control output of the control circuit such that the current source can be controlled by the control circuit and which is coupled via its output to the sensor electrode.
- the control circuit is set up such that when the current signal flowing into the control circuit via its input is outside a predetermined one
- the control circuit controls the current source in such a way that the current source adjusts the electrical current generated by it in such a way that the electrical current flowing into the input of the control circuit is brought to a predetermined current value. Furthermore, the control circuit is set up in such a way that when the current signal flowing into the control circuit via its input is within the predetermined current range, the control circuit controls the current source in such a way that the current source maintains the current generated by it at the current value. Furthermore, the circuit arrangement has a detection emitter with which the event can be detected that the current signal flowing into the control circuit via its input is outside the predetermined current range
- a sensor event takes place on the sensor electrode, for example the hybridization of a DM.A strand with an enzyme label on a catcher molecule immobilized on the sensor electrode, the enzyme producing free charge carriers when an appropriately suitable liquid is added this causes a flow of current at the sensor electrode causes a time-dependent change in the sensor current at the sensor electrode, as shown, for example, in FIG. 5.
- This sensor current I sensor has a characteristic influence on the current I C5S flowing through the input of the control circuit .
- the control circuit is set up in such a way that, if the current I OSS flowing through its input is outside the predetermined current range, the control circuit via its control output provides the control input of the current source with a signal such that the current source has such a current value I Rdnge at its output provides that the current I Mes flowing over the input of the control circuit is brought to the predetermined current value.
- a detection emhei which is preferably coupled to the control circuit, detects the event that the current signal I MC&S flowing into the control circuit via its input is outside the predetermined current range.
- the control circuit determines whether the current signal flowing into the control circuit via its input is within the predetermined range Current-strong range. If the current signal flowing into the control circuit via its input is within the predetermined range Current-strong range, the control circuit generates a corresponding signal at its control output, which is provided to the control input of the current source and causes it to keep the current i Ran g c generated by it at the current, constant value of the sensor current I cm so. generates a detection signal by a predetermined current interval, so that a sensor event of a sensor electrode is detected in this way
- the signal processing of the smallest currents in the pA-nA range is realized according to the invention, the analog current signal Is, e - s o r in the immediate vicinity of the sensor m being converted into a sequence of detection signals, for example pulses.
- a digitalization is carried out by changing / changing the analog current signal I> - i o m a chronological sequence of detection signals, preferably into a frequency as a result of the signal processing
- disruptive influences on the path of the sensor signal to a signal processing unit are avoided or kept low, which results in a high signal-to-noise ratio.
- the useful signal in the immediate vicinity of the sensor becomes the sensor signal Meetingflltert
- the sensitivity and dynamic range of the sensor or the signal processing unit can be flexibly adjusted to the needs of the individual case by means of the circuit arrangement according to the invention.
- FIG. 5 for example in the case of the detection of DNA Using the redox recycling principle, a transformation of the hybridization events stretches a signal current that rises constantly over time. through
- the sensitivity and dynamic range can be adjusted by dividing the measuring time and by setting the predetermined current range, the respective exceeding of which triggers a detection pulse.
- a desired dynamic range of five decades (for example for detecting electrical currents between lpA and lOOnA) can therefore be implemented very easily according to the invention.
- the circuit arrangement furthermore has a
- Detection unit has an electrically coupled counter element which is set up in such a way that it pays the number and / or the chronological sequence of the events detected by the detection unit
- the counter element is set up in such a way that if the electrical current flowing into the input of the control circuit exceeds an upper limit of the predetermined current range, the counter reading is increased by a predetermined value, if the counter current flowing into the input tu ⁇ g ele triscne Stro ⁇ n a lower limit of the given current range falls below, the counter reading is preferably decreased by a predetermined value.
- the described functionality of the payer element corresponds to the scenario that the sensor current has such a sign that the sensor current Is ens or is successively increased as a result of a sensor event.
- the counter reading is clearly increased by a predetermined value (preferably by “1”), whereas each
- the counter reading is decreased by a predetermined value (preferably by "1").
- the counter element is set up such that if the electrical current flowing into the input of the control circuit exceeds an upper limit of the predetermined current range, the counter reading is decreased by a predetermined value and that when the electrical current flowing into the input of the control circuit falls below a lower limit of the predetermined current range, the counter reading is increased by a predetermined value.
- the drop in the current value in a scenario in which a detection event increases the current value of a sensor electrode can be attributed, for example, to disturbing and parasitic events, v / ie noise events etc.
- the detector selectively detects the exceeding or falling short of the predetermined current range and consequently sets the counter reading of the counter element either up or down. In other words, it is automatic Averaging of the signal and errors due to noise effects etc. are thereby compensated. This leads to an increase in detection sensitivity
- the current source is preferably a voltage-controlled current source
- control circuit preferably has a current-voltage converter at its input, which is set up in such a way that that at the input of the
- Control circuit current is converted into an electrical voltage signal by means of the current-voltage converter.
- circuit arrangement according to the invention, it is designed as an integrated circuit.
- the integration of the circuit arrangement results in high detection accuracy as a result of the on-chip current signal processing.
- the current is processed directly on the chip and in the immediate vicinity of the sensor electrode , whereby disturbing signals, such as additional noise due to an increased transmission path, are avoided.
- the dimension of the circuit arrangement can be reduced as a result of the integration of the circuit arrangement according to the invention, for example into a semiconductor substrate. This miniaturization leads at a cost advantage, since macroscopic measuring equipment is saved
- a redox recycling sensor according to the invention is provided with a circuit arrangement with the features described above
- the sensitivity of the circuit arrangement according to the invention is sufficiently high to be able to detect very small electrical currents, which are usually produced when biomolecules of low concentration are detected. Therefore, the circuit arrangement of the invention is preferably designed as a redox recycling sensor with the features described above with reference to F ⁇ g.4A, F ⁇ g.4B, F ⁇ g.4C.
- each of the circuit arrangements of the sensor arrangements can be designed as a redox recycling sensor.
- the arrangement of a plurality of circuit arrangements for forming a sensor arrangement enables, for example, a parallel analysis of a liquid to be examined. If this liquid contains, for example, different biomolecules, such as different DNA half-strands, and are on the different ones If different types of capture molecules are immobilized in the sensor electrodes of the sensor arrangement, the different DNA half strands can be detected at the same time.
- the parallel analysis is a desirable measure of nationalization in many technical fields, by means of working time and thus cost savings Therefore, a time-saving analysis of a liquid to be examined is implemented according to the invention Furthermore, the method according to the invention is used
- the method for processing a current signal provided via a sensor electrode is carried out using a circuit arrangement with the features described above
- the current source is controlled by the control circuit in such a way that the current source adjusts the electrical current generated by it in such a way that it flows into the input of the control circuit flowing electrical current is brought to the predetermined current value If, on the other hand, the current signal flowing into the input of the control circuit is within the predetermined current range, the control circuit controls the current source in such a way that the current source fixes the electrical current it generates to the current value It is also detected by means of the detection unit that the current signal flowing through the control circuit via its input is outside the predetermined current range
- the number and / or the temporal sequence of the events is paid by means of a payer element which is electrically coupled to the control circuit
- a payer element which is electrically coupled to the control circuit
- the counter value is increased by a predetermined value.
- the payer level is lowered by a predetermined value
- the counter reading is reduced by a predetermined value and it becomes, if the electrical current flowing into the input of the control circuit becomes a lower limit of the predetermined current strength - falls below the range, the payer level increased by a predetermined value.
- FIG. 1 shows a schematic view of a circuit arrangement according to a first exemplary embodiment of the invention
- FIG. 2A shows a cross-sectional view of a sensor according to the prior art in a first operating state
- FIG. 2B shows a cross-sectional view of the sensor according to the prior art in a second operating state
- FIG. 3A shows a top view of interdigital electrodes according to the prior art
- FIG. 3B shows a cross-sectional view along the section line II 'of the interdigital electrodes shown in FIG. 3A according to the prior art
- FIG. 4A shows a biosensor based on the principle of redox recycling in a first operating state according to the prior art
- FIG. 4B shows a biosensor based on the principle of redox recycling in a second operating state according to the prior art
- FIG. 4C shows a biosensor based on the principle of redox recycling in a third operating state according to the prior art
- FIG. 5 shows a functional curve of a sensor current in the context of a redox recycling process
- FIG. 6 shows a detailed view of the functional curve of a sensor current in the context of a redox recycling process
- FIG. 7 shows a schematic view of a circuit arrangement according to a second exemplary embodiment of the invention.
- Figure 8A is a diagram that schematically shows the dependence of the sensor current of the time t for the sensor electrode shown in FIG. 7,
- FIG. SB shows a diagram which schematically shows the dependence of the measurement current I fS on the time t for the diagram shown in FIG. SA,
- FIG. 9A shows a schematic view of a circuit arrangement according to a third exemplary embodiment of the invention
- FIG. 9B is a diagram schematically showing the dependence of the measurement current I t es on the time t for the diagram shown in FIG. 8A and for the third exemplary embodiment of the circuit arrangement of the invention shown in FIG. 9A
- I t es the measurement current
- FIG. 10A shows a schematic view of a circuit arrangement according to a fourth exemplary embodiment of the invention.
- FIG. 10B is a schematic diagram of the detection unit of the fourth exemplary embodiment of the circuit arrangement of the invention shown in FIG. 10A
- the invention clearly illustrates, inter alia, an on-chip integrated circuit concept for the direct conversion of a sensor signal of an electronic biosensor, which is based on the principle of redox recycling, m frequencies.
- the signal that carries this frequency is in the form of binary signals with digital levels.
- FIG. 6 A basic idea for the frequency conversion of a sensor current signal according to the invention, which is implemented by means of the circuit arrangement according to the invention, is shown schematically in FIG. 6 using a diagram 600
- the diagram 600 shown in FIG. 6 has an abscissa 602, along which the time t is plotted.
- the sensor current Ic, C "sor is plotted along the ordinate 601 of the diagram 600.
- a current-time curve 603 is also shown.
- An offset current l o. ,,, . 604 the diagram 600 from FIG. 6 is also entered
- the current axis 601 is mentally divided into aquidistant sections of the large L l Ir aem time _nter / a 11 z ⁇ _sc ⁇ e ⁇ ⁇ e r 'first point in time t and the second point in time t . / 'earth how shown, the current-time curve 603 n swept over current intervals ⁇ I. According to the invention, it is appropriately detected how many complete sections n and therefore which current interval n ⁇ I from the sensor current I Senso ⁇ m the time interval between the first time t 0 and the second Time ⁇ be crossed over.
- the measurement-relevant size is the current increase m 605, i.e. the sensor current I] at the second time t
- circuit arrangement 100 based on the described principle is described below in accordance with a first preferred exemplary embodiment of the invention.
- the circuit arrangement 100 has a sensor electrode 101, a control circuit 102 which is coupled to the sensor electrode 101 via an input 103 and a current source 104 which is coupled via its control input 105 to a control output 106 of the control circuit 102 that the power source 104 from the
- Control circuit 102 is controllable, and which is coupled via its output 107 to the sensor electrode 101.
- the control circuit 102 is set up such that when the first current signal 108 flowing into the control circuit 102 via its input 103 is outside a predetermined current range, the control circuit 102 controls the current source 104 in such a way that the current source 104 controls the second one generated by it Current signal 109 sets such that the first current signal 108 flowing into the input 103 of the control circuit 102 is brought to a predetermined current value.
- control circuit 102 is set up such that when the first current signal 108 flowing into the control circuit 102 via its input 103 is within the predefined current strength range, the leveling circuit 102 controls the current source 104 in such a way that the current source 104 maintains the current current signal 109 generated by it at the current value.
- FIG. 1 Also shown in FIG. 1 are capture molecules 111 that are immobilized on the sensor electrode 101. Molecules 112 to be detected that are hybridized with these capture molecules 111 are also shown with an enzyme label 113.
- the system of the sensor which is based on the principle of redox recycling - Electrode 101, the catcher molecules 111, the molecules 112 to be detected with their enzyme labels 113, etc., causes electrically charged particles 114 to be generated, which generate a third current signal 115 from the sensor electrode 101.
- This third current signal 115 which is shown in FIG. 6 corresponds to the current-time curve 603 shown, contains the information as to which number of particles 113 to be detected are hybridized with the capture molecules 111 on the surface of the sensor electrode 101.
- the circuit arrangement 100 makes it possible to use the third current signal 115 to convert the sensors -Fill out information
- circuit arrangement 700 according to a second exemplary embodiment of the invention is shown
- the circuit arrangement 700 has a sensor electrode 701, a control circuit 702, v / elche is coupled to the sensor electrode 701 via an input 703 and a current source 704, v / elche via its control input 705 to the control output 706 of the control circuit 702 is controllable, and v / elche is coupled via its output 707 to the sensor electrode 701.
- the leveling circuit 702 is set up in such a way that the measuring current signal I s: jS flowing through the control circuit 702 via its input 703 703 is outside a predetermined current range, the leveling circuit 702 controls the current source 704 in such a way that the current source 704 the auxiliary it generates Current signal I- * at ge 7 09 is set such that the measurement current signal I ⁇ css 708 flowing into the input 703 of the control circuit 702 is brought to a predetermined current value I- Basc 7 i0.
- control circuit 702 is set up in such a way that If the measurement current signal 708 flowing into the control circuit 702 via its input 703 is within the predetermined current range, the control circuit 702 controls the current source 704 in such a way that the current source 704 maintains the auxiliary current signal 709 generated by it at the current value. Furthermore, the circuit arrangement 700 has a detection device 711 with which the event can be detected that the measurement current signal 708 flowing into the control circuit 702 via its input 703 is outside the predetermined current range.
- the predefined current range is monitored by means of a threshold value detector 712 of the control circuit 702.
- the predetermined one is
- FIG. 7 shows a counter element 714 which is electrically coupled to the detection unit 711 and which is set up in such a way that it pays the number and the chronological sequence of the events detected by the detection unit 711.
- Element 714 is set up such that, v / enn, the electrical current flowing into the input 703 of the leveling circuit 702
- the sensor current signal Is-r So: 715 which is generated as a result of sensor events at the sensor electrode 701, is shown in FIG.
- the time profiles of the measurement current signal 708 (diagram 716), the auxiliary current signal 709 (diagram 717) and the sensor current signal 715 (diagram 718) are shown in diagrams 716, 717, 718.
- diagrams 716 and 717 show an ideally desired time dependency of measurement current signal 708 and auxiliary current signal 709
- diagrams 719 and 728 show a real time dependence of measurement current signal 708 and auxiliary current signal 709 show.
- Measuring current signal 708 (diagram 716) or auxiliary current signal 709 (diagram 717) to approximate.
- the measurement current signal 708 or the auxiliary current signal 709 by means of an ideal curve, as in diagram 716 or diagram 717 shown, is writable.
- the current source 704 shown in FIG. 7 is a voltage controlled current source.
- the control circuit 702 has a current-voltage converter 720 at its input 703, which is set up in such a way that the measurement current signal 708 present at the input 703 of the control circuit 702 by means of the current-voltage converter 720 is converted into an electrical voltage signal.
- the components of the circuit arrangement 700 are integrated in a silicon substrate (not shown in FIG. 7), or a part of the components is formed on the silicon substrate.
- the circuit design shown in Fig .7 constitutes a realization of the erf dungsge responsiblyen principle.
- the TIC idea is based on the use of three over an electrical node 721 interconnected current signals I MCSS 708, I Ra length 709 and I SC nsor 715th
- the sensor current Is e ⁇ so ' - 715 denotes the electrical current that flows from the sensor electrode 701 as a result of sensor events that have taken place on the sensor electrode 701 (cf. FIG. 1).
- a typical time dependency of the sensor current Is cnsor 715 is shown in diagram 718.
- the time dependency shown there essentially corresponds to the current-time curve 603 described above with reference to FIG. 6. Such a curve is obtained, for example, during detection according to the Reclox recycling method.
- Diagram 718 shows schematically that the sensor current Ise n s or 715 is mentally divided into intervals ⁇ I.
- Fig. 7 shown embodiment of the circuit arrangement 700 st for the given Current value l 3 se 700 selected as value OA.
- the selection of a predetermined current value I B ⁇ SP 710 that deviates from the current value 0A can be favorable.
- circuit arrangement 700 has the effect that the information relevant to the analysis of the sensor events relating to the current rise m is contained in the measurement current signal I Mo & ⁇ 708, whereas the auxiliary current signal IRang e 709 e ne Auxiliary function fulfilled.
- t denotes a current point in time and t ' a specific point in time that is earlier than the current point in time t.
- a time interval that corresponds to the first operating state ⁇ 1 ⁇ is exemplified in the diagrams 716, 717, 718 (and also diagram 719) with the reference number 722.
- the auxiliary current signal IJ a - ⁇ ... 709 fixed to a constant time-independent current current value This current value is determined by the difference between the sensor current I ⁇ cn «; ⁇ r (t * ) 715 as it flowed at the previous point in time t " and is determined by the predetermined current value Ia asc 710 (cf. (6b)).
- the measurement current signal I MCS ⁇ 708 at the point in time t is the sensor by the difference Current signals 715 at times t and t * plus the specified current value Iea se 710 (see (6b)).
- the measurement current signal 708 is within the specified current Area 713
- the operating state ⁇ 2 ⁇ is characterized in that the sensor current signal 715 generated at the sensor electrode 701 at the time t, reduced by the predetermined one
- the measurement current signal I MLS . is consequently at the time t independent of the sensor current signal I cnsor 715 at the predetermined current value Iba ⁇ e 710 (cf. (7a)).
- the predetermined current value I b a o 710 which, as mentioned above, is selected as 0A according to the exemplary embodiment described, is therefore used to set a working range of the measuring current signal I Moa ⁇ 708.
- the entire sensor current signal I n so r 715 is the auxiliary current signal Ip aPgo 709 in the operating state ⁇ 2 ⁇ , so that the measurement current signal I n n. S 708 disappears.
- the operating state ⁇ 2 ⁇ is shown in FIG. 7, for example, by the point in time designated by the reference number 723, which is shown in the diagrams 716, 717, 713.
- the finite duration of the second operating state ⁇ 2 ⁇ 723a is, however, irrelevant, so that in the further description it is assumed that the second operating state (2 ⁇ 723 can essentially be described by means of a point in time.
- the meaning of the time interval ⁇ t is given below described generation of a detection pulse (the temporal length ⁇ t) again Iffen.
- the two operating states ⁇ 1 ⁇ and ⁇ 2 ⁇ 722, 723 are controlled in the circuit arrangement 700 by the control circuit 702 and the voltage-controlled current source 704.
- Current source 704 is controlled by the control circuit 702 by means of a parameter y, which in the case of the circuit arrangement 700 is an electrical voltage.
- the current source 704 is a voltage-controlled current source.
- the measurement current signal I i 703 is by means of the current voltage -Converters 720 transformed into a variable ⁇ , which is an electrical voltage according to the circuit arrangement 700 described in FIG. 7. This voltage is the output variable of the current-voltage converter 720 and the input variable of a leveling device is called 724
- the control unit 724 is provided with the information as to whether the circuit arrangement is to be operated in the operating state ⁇ 1 ⁇ or in the 5 operating state ⁇ 2 ⁇ .
- control unit 724 is set up in such a way that one
- Another area of the circuit arrangement 700 namely the threshold value detector 712 of the control circuit 702, the detection unit 711 and the counter element 714 define when of the circuit arrangement 700 the operating state
- the output of the threshold value detector 712 such a signal is generated 5 and provided to the input of the detection unit 711 that the detection unit 711 generates a pulse 727.
- the pulse 727 generated by the detection unit 711 is made available to the further input 725 of the control unit 724.
- Control unit 724 provided pulse 0 informs control unit 724 that the predetermined threshold value 726 at threshold value detector 712 has been exceeded, which is the case when the measurement current signal IM, SS 703 exceeds the value I_ sb ⁇ + LI Exceeding the threshold 726 is equivalent to the event that the measurement current signal I. " , -s & 708 exceeds the predetermined current range 713 has, that is, has exceeded the current value I 3e ._.-Ll.
- the temporal length of the pulse 727 of the detection emitivity 711 corresponds to that length which is designated in diagram 719 as the real length of the second operating state 723a with ⁇ t. It may be advantageous for the pulse 727 generated by the detection unit 711 to have a time length ⁇ t-0 that is as short as possible.
- the pulse 727 provided at the further input of the control unit 724 causes the control unit 724 to regulate the circuit arrangement 700 during the time period ⁇ t of the pulse 727 in such a way that the second operating state ⁇ 2 ⁇ is maintained during this time interval ⁇ t.
- the circuit arrangement 700 is in the operating state ⁇ 1 ⁇ .
- the result of the interaction of all circuit components of the circuit arrangement 700 is shown in the diagrams 716, 717, 718; if the measurement current signal I H , JiS , 708 exceeds the value iBase ⁇ ⁇ I, the measurement current signal IMe is reset, to the specified current value Iea so 710 using the operating state ⁇ 2 ⁇ . After the reset, the measurement current signal I M «& s 708 again increases at a rate which is determined by the sensor current signal Is 0 n so r 715.
- the pulses 727 generated by the detection unit 711 in each reset operation are not only provided to the further input 725 of the control unit 724, but also, as shown in FIG. 7, to the payer element 714.
- the payer element 714 pays the number of pulses and their chronological order. In other words, the payer element 714 detects the number n of pulses in digital form, which means that the payer element 714 can be used to determine which current intensity / acns / acns n ⁇ I has occurred in the measured time period
- n is identical to the number of If the sensor current signal I ⁇ enso 715 is exceeded via ⁇ I sections within the time period t 0 -t ⁇ , the large ⁇ t should preferably be negligibly small compared to the time between two resetting processes. Under this condition, which is often easy to achieve in practice, the current increase m * can be determined via n. If n is sufficiently large or ⁇ I is sufficiently small or the measuring time is selected to be sufficiently long, then m can be assumed to be approximately equal to m ' .
- the described method for processing a sensor current signal 715 provided via a sensor electrode 701 can also be used if the time interval ⁇ t, i.e. the length of the pulse 727 is not negligibly small. In one
- the scenario is to determine the m * to be measured using the following expression:
- the frequency of the pulses 727 at the output of the detection unit 711 can also be detected directly.
- the information of the sensor current signal 1 s e n so r 715 is contained in this frequency.
- the 700-based methods of the circuit arrangement on the Verv / extension for processing a provided on the sensor electrode 701 sensor current signal Is ".n" o r 715 In summary, the following steps: v / hen the in the control circuit 702 Via its input 703 flowing measurement current signal I.
- the control circuit 702 controls the current source 704 in such a way that the current source 704 generates the electrical auxiliary current signal I »£ .- C ⁇ generated on it 709 so that the input 703 of the
- the control circuit 702 flowing electrical measurement current signal Ij-i ess 708 is brought to the predetermined current value I Da «, 0 710 if the measurement current signal I ,,,, « 708 flowing into the control circuit 702 via its input 703 is within the predetermined Is current-strong area 713, the control circuit 702 controls the current source 704 in such a way that the current source 704 maintains the electrical auxiliary current signal ⁇ Ranq e 709 generated by it at the current value.
- the event is also detected by means of the detection unit 711 detects that in the
- Control circuit 702 via its input 703 flowing measurement current signal ⁇ M e s s 708 is outside the predetermined current range 713
- FIGS. 8A and 8B it is described how the principle according to the invention works when the sensor current signal I ⁇ n sor deviates from its ideal linear form (see FIG. 6) and signal fluctuations (for example as a result of noise effects) ) occur.
- a diagram 800 is shown in FIG. 8A, along which the time t 802 is plotted along the abscissa and the electrical sensor current 801 is plotted along the ordinate. As shown in FIG. 8A, the curve shape sensor current time 803 is not linear, but has fluctuations
- FIG. 8B A further diagram 810 is shown in FIG. 8B, along the abscissa of which the time 812 is plotted, which corresponds to the time 802 plotted in FIG. 8A.
- the electrical measurement current 311 is plotted along the ordinate of the other diagram 310
- FIG. 8B plots the curve current Stro time 813 as it results from the operation of the circuit arrangement 700 according to the invention in the event that the curve curve sensor current time 303 shown in FIG. 8A is present
- m Fig. 8A is a current intensity - I r ter al 1 ⁇ I 30- shown.
- the predetermined current strength range essential for the functionality of the circuit arrangement according to the invention that is to say the range between a predetermined current strength value ⁇ BaS 814 and I Bc - s0 + ⁇ I, is identified in FIG. 8B with the reference number 815
- the method based on the circuit arrangement according to the invention for processing a current signal provided via a sensor electrode is therefore robust against signal fluctuations
- FIG. 9A shows a circuit arrangement 900 according to a third exemplary embodiment of the invention, which is a further development of the circuit arrangement shown in FIG. 7
- circuit arrangement 700 represents Those elements of the circuit arrangement 900 from FIG. 9A that are identical to components of the circuit arrangement 700 are provided with the same reference numerals in FIG. 9A and are not explained in more detail below.
- the circuit arrangement 900 shown in FIG. 9A has the advantageous further development that the electrical measuring current is also limited downwards.
- the circuit arrangement 900 has the following components - a control circuit 901, the control unit 905 of which has a first further input 906a and a second further input 906b instead of the further input 725 from FIG
- the detection unit of the circuit arrangement 900 shown in FIG. 9A has a first region of the detection unit 902a and a second region of the detection unit 902b.
- the Schv / ellv / ert detector of the circuit arrangement 900 has a first Area of the threshold value detector 903a and a second area of the threshold value detector 903b on.
- the saving signal ⁇ provided by the current-voltage converter 720 at its output is sent to the control unit 905 and both the first area of the threshold value detector 903a also provided the second area of the threshold value detector 903b
- the first area of the threshold value detector 903a essentially fulfills the same functionality as the threshold value detector 712 shown in FIG. 7, if the voltage signal x provided by the current-voltage converter 720 to the input of the first area of the threshold value detector 903a exceeds a first predetermined threshold value 907a of the first area of the threshold value detector 903a, a corresponding signal is transmitted from the output of the first area of the threshold value detector 903a to the input of the first area of the detection unit 902a coupled to this output.
- the first area of the detection unit 902a has an output which is coupled to the first further input 906a of the control unit 905 and which is coupled to the first input 904a of the payer element 904.
- the first area of the detection unit 902a generates a first pulse 908a, which is provided to the first further input 906a of the control unit 905 and which is provided to the first input 904a of the payer element 904.
- the first pulse signal 908a causes the first further input 906a of the control unit 905 to reset the measurement current signal I Me t, s 708 from the value I Ba & o + ⁇ I to the value ⁇ base .
- the first pulse 908a at the first input 904a of the payer element 904 causes the payer status of the payer element 904 to be a predetermined one
- circuit arrangement 900 corresponds to that of the circuit arrangement 700
- the voltage signal x generated by the Stro.m voltage converter 720 which is characteristic of the current measurement current signal 703, is provided to the second area of the threshold value detector 903b at its input. If the voltage signal x falls below the second predetermined threshold value 907b second area of the threshold value detector 903b, so at the output of the second area of the threshold value detector 903b, which with the input of the second region of the detection unit 902b is coupled, a corresponding electrical signal is generated and this is transmitted to the input of the second region of the detection unit 902b, in this case a second pulse 908b is generated by the second region of the detection unit 902b , The output of the second area of the detection unit 902b is coupled both to the second further input 906b of the control unit 905 and to the second input 904b of the payer element 904.
- the second pulse 908b if it is generated at the second area of the detection unit 902b, is provided to these two inputs.
- the scenario described corresponds to the scenario designated in FIG. 9B at time 927, in which the measurement current signal 708 reaches the lower limit I Basc - ⁇ I of the predetermined current range 925. That the
- Control unit 905 at its second further input 906b provided second pulse signal 908b controls the current source 704 in such a way that the measurement signal ⁇ measurement 708 is reset to the predetermined current value ⁇ a a- , c 924.
- Raising the sensor current by a further current range 804 is the cause, but rather a reduction in the current signal, for example due to noise effects
- E " r £ I the circuit arrangement shown in FIG. 9A represents an advantageous further development of the circuit arrangement 700, since the decrease in the measurement current signal 703 can also be correctly detected by means of the circuit arrangement 900.
- the counter element 904 of the Circuit arrangement 900 is designed as a forward / reverse payer.
- circuit arrangement 900 from FIG. 9A is described below with reference to the diagram 920 from FIG. 9B.
- the diagram 920 has an abscissa along which the time 922 is plotted.
- the electrical measuring current 921 is plotted along the ordinate.
- the measurement current-time curve 923 is also shown, as is obtained using the circuit arrangement 900 shown in FIG. 9A in the case of a sensor current-time curve 803, as shown in FIG. 8A.
- the electrical measuring current 921 remains within the predefined current strength range 925 around the predefined current strength value ⁇ base 924 with a bandwidth ⁇ I extending upwards or downwards.
- FIG. 9B also shows first reset points 926a and a second reset point 926b. A comparison of the measurement current-time curve 923 with that
- Curve sensor current time 803 shows that the first reset points reflect a respective increase in sensor current 801 by a further current intensity interval 804, whereas reset point 926b shows the fall back of sensor current 801 to be recorded at time 927 around a
- a fourth preferred exemplary embodiment of a circuit arrangement 1000 according to the invention is described in detail below with reference to FIG. 10A, FIG. 10B.
- the circuit arrangement 1000 shown in FIG. 10A represents a circuit implementation of the circuit arrangement 700 shown in FIG. 7. Therefore, those are
- Circuit blocks of the circuit arrangement 1000 which are configured as an equivalent element in the circuit arrangement 700, are provided with the same reference numbers.
- the sensor electrode 701, from which the sensor-current signal 715 flows, is coupled to the one source-drain region of a first p-MOS transistor 1001, which forms the current-voltage converter 720. Furthermore, the electrical node 721 is coupled to the one source-drain region of a second p-MOS transistor 1002.
- the measurement current signal I Me s ⁇ , 708 flows between the electrical node 721 and the first p-MOS transistor 1001, and the auxiliary flows between the node 721 and the one source-drain region of the second p-MOS transistor 1002 Current signal Ip ar ⁇ g e .
- the gate region of the first p-MOS transistor 1001 is coupled to a second electrical node 1003.
- the second electrical node 1003 is coupled to a third electrical node 1004.
- the third electrical node 1004 is coupled to the output of a first operational amplifier 1005. Furthermore, the third electrical node 1004 is connected to the one source-drain region of a third p-MOS transistor 1006 coupled
- the non-inverted input of the first operational amplifier 1005 is coupled to the electrical node 721.
- the non-inverted input of the first operational amplifier 1005 is connected to a first
- Reference voltage source 1007 coupled The other source-dram region of the first o-MOS transistor 1001 is connected to the a source-drain region of a fourth p-MOS transistor 1008 coupled.
- the other source-drain region of the fourth p-MOS transistor 1008 is coupled to a supply voltage source 1009.
- the gate region of the fourth p-MOS transistor 100S is with a fourth electrical
- the fourth electrical node 1010 is coupled to the output of the detection unit 711 and to the input of the counter element 714.
- the second electrical node 1003 is further coupled to the inverted input of a second operational amplifier 1011. The non-inverted input of the second
- Operational amplifier 1011 is coupled to a second reference voltage source 1012.
- the output of the second operational amplifier 1011, to which a first output signal 1013 can be applied, is coupled to the input of the detection unit 711.
- Another output of the detection unit 711 is coupled to the gate region of the third p-MOS transistor 1006.
- the other source-drain region of the third p-MOS transistor 1006 is coupled to a fifth electrical node 1014.
- the fifth electrical node 1014 is coupled to the gate region of the second p-MOS transistor 1002 and to a storage capacitor 1015.
- the storage capacitor 1015 is also coupled to a sixth electrical node 1016.
- the sixth electrical node 1016 is also coupled to the other source-drain region of the second p-MOS transistor 1002.
- the sixth electrical node 1016 is also coupled to the supply voltage source 1009.
- the detection unit 711 is set up in such a way that the detection unit 711 corresponds to a scenario in which the input of the detection unit 711 from the threshold value detector 712 has a first output signal
- the detection unit 711 is designed such that in a scenario in which the detection unit 711 a first output signal 1013 is provided by the threshold value detector 712, the detection unit 711 provides a second pulse 1018 to the gate region of the third p-MOS transistor 1006.
- the exact configuration of the payer 714 is not shown in FIG. 10A.
- the counter 714 can be, for example, a synchronous dual counter constructed from JK flip-flops.
- the circuit arrangement 1000 shown in FIG. 10A in contrast to the circuit arrangement 700 shown in FIG. 7, has an electrical coupling means 1019 for coupling the electrical node 721 to the control unit 725, more precisely with the non- inverted input of the first operational amplifier 1005 of the control unit 725, in order to achieve the function of the electrical node 721 as a summation point according to equation (5), it should be ensured that the current in this additional line is formed by the electrical coupling means 1019 disappears If the transistors of the ⁇ mgangs differential stage of the first operational amplifier 1005 are designed as MOS transistors, this requirement is well met
- the output of the first operational amplifier 1005 is fed back to the non-inverted input by means of the second or first p-MOS transistor 1002, 1001. Furthermore, the open loop gain of the first operational amplifier 1005 is denoted by AI. Then, as long as the feedback takes place ensures that the first operational amplifier 1005 is not limited
- V 0ut 1 ⁇ t is the voltage applied to the output of the first operational amplifier 1005
- V is the voltage applied to the electrical one
- V ⁇ V ⁇ Lds + ouc / Al (10)
- the potential at the electrical node 721 thus becomes the value V_ predetermined by the first reference voltage source 1007 at the inverted input of the first operational amplifier 1005 .
- __ regulated This voltage value which simultaneously determines the electrical potential at the sensor electrode 701, is required in order to close the process of Pedo ⁇ rec / cling enable
- the first control state 1020 and the second control state 1021 are described in more detail below
- the first control circuit 1020 will be described, which corresponds to the operating state of the circuit arrangement according to the invention denoted above with operating state ⁇ 1 ⁇
- This case corresponds to the scenario that the detection unit 711 does not generate a first pulse 1017 and a second pulse 1018 at its output and at its further output.
- the gate region of the fourth p-MOS transistor 1008 is conductive.
- the detection unit 711 does not generate a second pulse 1018 which, as shown in FIG. 10A, starting from a logic value "0" for the duration of the pulse, would generate the logic value "1”
- the gate area is the third p-MOS transistor 1006 is not conductive.
- the gate region of the third p-MOS transistor 1006 is not conductive, whereas the gate region of the fourth p-MOS transistor 1008 is conductive
- the gate region of the third p-MOS transistor 1006 is not conductive, a constant electrical voltage is applied to the storage capacitor 1015 and thus to the gate region of the second p-MOS transistor 1002 at the electrical node 721 there is also a constant electrical voltage, there is a time-dependent auxiliary current 1 ⁇ - ⁇ . 709 through the gate region of the second p-MOS transistor 1002.
- the sensor current i s . ", 715 which changes over time, therefore flows through the gate region of the first p-MOS transistor.
- the electrical voltage at the output of the first ooeratio ⁇ s / starter 1005 is such that the electrical voltage at the gate region of the first p-MOS transistor 1001 enables the required current flow.
- the second control circuit 1021 is described below, which corresponds to the operating state of the circuit arrangement 1000 referred to above as the operating state ⁇ 2 ⁇ .
- the detection unit 711 generates a first pulse 1017 at its input as a result of a corresponding first output signal 1013 and a second pulse 1018 at its two outputs.
- the first pulse 1018 is set up in such a way that the Gate region of the third p-MOS transistor 1006 becomes conductive.
- the first pulse 1017 is set up in such a way that the gate region of the fourth p-MOS transistor 1008 does not become conductive during the pulse duration.
- the gate region of the third p-MOS transistor 1006, on the other hand, is in the conductive state, and according to this scenario, the output voltage of the first operational amplifier 1005 is the gate voltage of the second p-MOS transistor 1002, and therefore controls the auxiliary Current Ilange, which flows through the gate region of the second p-MOS transistor 1002.
- the gate voltage of the second p-MOS transistor 1002 is regulated by the circuit arrangement 1000 such that the auxiliary current 709 is equal to the sensor current I, b ⁇ r 715.
- the total sensor current of the sensor electrode 701 is therefore derived from the range channel
- the auxiliary current ⁇ range 709 is stored by means of the electrical voltage on the storage capacitor 1015 by means of the second p-MOS transistor 1002. Therefore, in the first operation state 1020, the sensor current I is HES5, 708 of the sensor current Is u n sor 715 less costs to the stored auxiliary current I Ra ng e 709th
- the third and fourth p-MOS transistors 1006, 1008 are driven by means of the second pulse 1018 and the first pulse 1017 of the detection unit 711.
- the sensor current ⁇ ens ⁇ increases r 715 to a larger measurement current ⁇ measurement 708.
- the gate voltage of the first p-MOS transistor 1001 decreases accordingly. If the gate voltage falls below the value of the voltage of the second reference voltage source 1012 of the second operational amplifier 1011, then generates a positive edge at the output of the second operational amplifier 1011 (which acts as a comparator). This edge stimulates the detection unit 711 to generate a pulse.
- the detection unit is set up in such a way that in the normal state the two outputs of the detection unit 711 switch the operating state ⁇ 1 ⁇ 1020.
- the gate 3ere ⁇ ch of the third p-MOS transistor 1006 is conductive, whereas the gate region of the fourth p-MOS transistor 1008 is not conductive
- the measuring current MCSS 708 is reduced to the value 0, and at the same time a new auxiliary current is ranked c 709.
- the number of reset processes is determined by registering the number of pulses using the payer Elements 714 realized, the number or the temporal sequence of the pulses are stored digitally in the counter element 714
- the exemplary embodiment of the detection unit 711 described in FIG. 10B shows how, starting from the first output signal 1013 of the threshold value detector 712, a pulse of the temporal length ⁇ t can be generated which for a period of time ⁇ t produces a signal with a logical value "1" to provides, whereas before the pulse and after the pulse the signal assumes a logical value "0". Such a pulse corresponds to pulse 1018 shown in FIG. 10A.
- Pulse 1017 from FIG. 10A can be generated, for example, by first generating a pulse of the type of the second pulse 1018 and subtracting this pulse from a constant signal.
- the detection unit 711 shown in FIG. 10B has a flip-flop 1050 with a first input 1051, a second input 1052 and an output 1053.
- the first input 1051 is the edge-sensitive input of the flip-flop 1050, and at this input the first output signal 1013 defined and shown in FIG. 10A is applied.
- the output 1053 of the flip-flop 1050 is brought from a logic value "0 'to a logic value" 1 ".
- the output 1053 of the flip-flop 1050 is coupled to an electrical node 1054 This electrical node is coupled to an ohmic resistor 1055.
- the ohmic resistor 1055 is coupled to a second electrical node 1056 second electrical node 1056 is coupled to a capacitor 1057.
- the second electrical node 1056 is coupled to a first amplifier stage 1058, and the first amplifier stage 1058 is coupled to a second amplifier stage 1059.
- the second amplifier stage 1059 is coupled to the second input 1052 of the flip-flop 1050.
- the functionality of the amplifier stages 1058, 1059 can be seen in the fact that defined logic levels are present at the second input 1052 of the flip-flop 1050.
- the output edge at the Output 1053 of flip-flop 1050 is delayed by means of the RC element formed from ohmic resistor 1056 and capacitor 1057 and used as a reset for flip-flop 1050.
- a pulse of length ⁇ t proportional to RC is generated, where R is the Resistance value of the ohmic resistor 1055 and C the capacitance of the capacitor 1057 is therefore the pulse duration is essentially determined by an RC element.
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Abstract
Description
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Priority Applications (3)
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US10/503,275 US20060292708A1 (en) | 2002-02-01 | 2003-01-17 | Circuit arrangement, redox recycling sensor, sensor assembly and a method for processing a current signal provided by a sensor electrode |
EP20030706229 EP1470430A1 (de) | 2002-02-01 | 2003-01-17 | Schaltkreis-anordnung, redox-recycling-sensor, sensor-anordnung und verfahren zum verarbeiten eines über eine sensor-elektrode bereitgestellten stromsignals |
JP2003564599A JP2005525540A (ja) | 2002-02-01 | 2003-01-17 | 回路構造、レドックス再生利用センサー、センサー構造、および、センサー電極によって供給された電流信号の処理方法 |
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DE10203996A DE10203996A1 (de) | 2002-02-01 | 2002-02-01 | Schaltkreis-Anordnung, Redox-Recycling-Sensor, Sensor-Anordnung und Verfahren zum Verarbeiten eines über eine Sensor-Elektrode bereitgestellten Stromsignals |
DE10203996.8 | 2002-02-01 |
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US (1) | US20060292708A1 (de) |
EP (1) | EP1470430A1 (de) |
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US8262875B2 (en) * | 2004-09-17 | 2012-09-11 | Siemens Aktiengesellschaft | Sensor arrangement and method for detecting a sensor event |
CN110632371A (zh) * | 2019-09-30 | 2019-12-31 | 深圳供电局有限公司 | 一种物体表面带电非接触式检测装置及方法 |
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KR20200064076A (ko) * | 2017-09-29 | 2020-06-05 | 베링거잉겔하임베트메디카게엠베하 | 회로 배열의 테스팅 및 교정 |
DE102018218122B4 (de) * | 2018-10-23 | 2023-02-16 | IMMS Institut für Mikroelektronik- und Mechatronik-Systeme gemeinnützige GmbH (IMMS GmbH) | Vorrichtung und Verfahren zur Analyse biologischer, chemischer und biochemischer Substanzen |
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Also Published As
Publication number | Publication date |
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US20060292708A1 (en) | 2006-12-28 |
JP2005525540A (ja) | 2005-08-25 |
DE10203996A1 (de) | 2003-08-21 |
EP1470430A1 (de) | 2004-10-27 |
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