856 results about "Equivalent capacitance" patented technology

In order to overcome problems when using an adaptive filter for cancellation of common-mode noise in digital subscriber loops, caused by a portion of the differential signal being converted to common mode, which degrades the performance of the filter, a noise cancellation technique is proposed which compensates for this cross-coupled signal energy. In particular, a digital noise detector is used to detect one or more noisy frequency bands of the common mode signal and pass only the digitized common mode signal in those detected frequency bands through the adaptive filter to produce a digital common mode noise estimate signal. A control unit adjusts coefficients of the adaptive filter to reduce correlation between the differential signal and common mode signal. It is also proposed to compensate for the effects of stray capacitive coupling across the usual hybrid device by including an equivalent capacitive component in a common mode noise estimation circuit.

The invention is a determining method for a touch control induction device comprising a touch control pad at least connected to m X n equivalent capacitors, where m is number of equivalent capacitors in the X-axis direction and n is that in the Y-axis direction, and the determining method comprises the steps of: charging m equivalent capacitors of a column to obtain m digital signals; comparing them with one another and using the smallest as a potential reference value; repeating the above two steps to obtain n potential reference values; touching the touch control pad; scanning the touch control pad to obtain at least a potential variation value relative to m equivalent capacitors of at least a column; and comparing the potential reference value with the potential variation value to determine which point in this column on the touch control pad is touched.

An object position detecting device includes a touch film, a first electrode set, a second electrode set, and a sensing and computing circuit. An object position detecting method includes the following steps. Firstly, an object is provided on the touch film. Then, first equivalent capacitance values of multiple first electrode groups of a first electrode set under the touch film are sensed, wherein each first electrode group includes n adjacent first electrodes that are parallel with and connected with each other. Then, second equivalent capacitance values of multiple second electrode groups of a second electrode set under the touch film are sensed, wherein each second electrode group includes m adjacent second electrodes that are parallel with and connected with each other. According to the first equivalent capacitance values and the second equivalent capacitance values, first position information of the object is calculated.

A stud or joist sensor device and associated sensing method using a ratio of capacitance measurements from a plurality of capacitive sensing elements. The device locates a feature of an object or discontinuity behind a surface or wall, such as an edge and/or a center of a stud behind the surface, a joist under a floorboard, a gap behind sheetrock, a metal conductor behind a surface or the like. The device may be moved over a surface, thereby detecting changes in capacitance. The change in capacitance is due to the effective dielectric constant caused by the passage over an object such as a stud. When two capacitive sensing elements provide equivalent capacitance measures, the device is over a centerline of the stud. When a ratio of the capacitance measurements equals a transition ratio, the device is over an edge of the stud.

An identification method for a touch control device having a memory and a pad electrically connected to an equivalent capacitance is provided. The provided identification method for a touch control device includes steps of: (a) charging the equivalent capacitance for obtaining a first voltage value; (b) storing the first voltage value in the memory; (c) touching the pad; (d) scanning the pad for obtaining a second voltage value of the equivalent capacitance; and (e) comparing the first voltage value with the second voltage of the equivalent capacitance for identifying a touched position on the pad.

The invention relates to a capacitive touch screen for improving the edge touch sensitive accuracy and a method for eliminating edge effect by compensating coordinate data of a touch position. The touch screen comprises plate electrode groups in the same plane or belonging to different planes, and under normal working conditions, the plate electrode groups form equivalent capacitance arrays by mutual orthogonal of rectangular strip-shaped equivalent plate electrodes in the plane of the touch screen. The width of the equivalent plate electrodes positioned at the edge of the touch screen in theequivalent capacitance arrays is smaller than the width of the equivalent plate electrodes which are positioned in the middle of the touch screen and arranged along the same direction of the equivalent plate electrodes. The invention reduces the width of the equivalent plate electrodes at the edge, increases the information quantity retrievable by the touch action on the edge of the touch screen,improves the sensitivity of the edge of the touch screen, reduces the error of center coordinate data, and solves the problem of edge effect of the touch screen; and in addition, by applying the method for compensating the coordinate data of the touch position provided by the invention, the touch accuracy at the edge of the touch screen is further improved.

The invention discloses a digital-to-analog converter with a sectional capacitor array structure. The digital-to-analog converter comprises at least two capacitor subarrays and at least one bridging capacitor CB, wherein each bridging capacitor CB is connected with two qualification-bit capacitor subarrays with adjacent weights; the low-level capacitor subarray of each bridging capacitor CB is connected with a compensating capacitor CC with an adjustable capacitance value in parallel; the compensating capacitor CC enables the capacitance value of an equivalent capacitor in the compensated low-level capacitor subarray to be equal to that of the lowest-level capacitor in the high-level capacitor subarray connected with the bridging capacitor CB. The digital-to-analog converter disclosed by the invention has the advantages that by adoption of the embodiment, the compensating capacitor CC with the adjustable capacitance value is introduced, and the capacitance value of the compensating capacitor CC is set according to the bridging capacitor CB and parasitic capacitors at common nodes of the capacitor subarrays at the two ends, so that the capacitor mismatching among the capacitor subarrays is eliminated, the linearity is further improved while gain error is eliminated, and DNL (Differential Non Linearity) and INL (Integral Non Linearity) of a successive approximation ADC (Analog to Digital Converter) are finally improved.

A controlling device for the cursor and the method for operating the same are provided. The controlling device includes a capacitor array having a plurality of equivalent capacitors, a microprocessor electrically connected to the capacitor array for sending a pulse train to the capacitor array in the x-direction and receiving a potential of each equivalent capacitor in the y-direction so as to determine a movement of a cursor, and a charge-absorbing device disposed above the capacitor array, wherein when the charge-absorbing device is moved correspondingly to a position of a specific equivalent capacitor in the capacitor array, a storage charge of the specific equivalent capacitor is absorbed so that the potential thereof is lowered, and thereby the movement of the cursor is determined by the microprocessor.

The invention relates to a fingerprint sensing device and a related fingerprint sensing touch device, which are provided with specially designed sensing units capable of improving the accuracy of fingerprint sensing. The fingerprint sensing device comprises a plurality of sensing units, a driving circuit and a reading circuit, wherein each sensing unit comprises a fingerprint electrode and a storage capacitor, the storage capacitor is coupled with the fingerprint electrode, and induction capacitance formed between the fingerprint electrode and a finger is connected with the storage capacitor in parallel; the driving circuit is coupled with the sensing units and can provide charging signals for charging the equivalent capacitance of each sensing unit, wherein, the equivalent capacitance value of any sensing unit is determined according to whether the sensing unit forms the induction capacitance or not; and the reading circuit is coupled with the sensing units and can read the voltage value of the storage capacitor of the sensing units after the equivalent capacitance of any sensing unit is charged, thereby judging whether the fingerprint is sensed and whether the sensed fingerprint is a ridge or a valley.

Disclosed herein are a capacitive type touch detection means and a detection method using a new scheme, which detects a touch signal using a difference between voltage magnitudes detected by a touch detector according to whether a touch is generated, when an alternating voltage is applied to a line equivalent capacitor formed between a sensing pad which is detecting a touch signal and a non-sensing pad adjacent to the sensing pad. The touch detection means includes: a sensing pad configured to generate the touch capacitance Ct between a sensing pad and the touch input means; an alternating voltage configured to be applied to a line equivalent capacitor Ceq formed between the sensing pad and a non-sensing pad adjacent to the sensing pad; and a touch detector connected to the sensing pad to detect a difference in voltage generated according to whether the touch is generated by the touch input means.

A method for increasing a signal to noise ratio of a capacitive touch device and a capacitive touch device and a touch panel using the same are provided. The capacitive touch device includes a first sensing electrode, a second sensing electrode, a touch detector, a resonant inductor and a detection signal output circuit.

An output terminal of the detection signal output circuit outputs a detection signal, such that the resonant inductor and an equivalent capacitor of the first sensing electrode are resonant, and the first sensing electrode receives a resonant sinusoidal wave. When an electric field signal detected by the detecting terminal of the touch detector is smaller than a preset value, it is determined that the capacitive touch device is touched.

A self-calibration circuit for capacitance mismatch is provided. The circuit comprises a sample-and-hold (S/H) circuit, a comparator, and a switch control circuit. The S/H circuit comprises a compensation capacitor array, a target capacitor, and a reference capacitor. The S/H circuit provides an output voltage, wherein the output voltage is an operation result based on the capacitance of the target capacitor and the reference capacitor, and the equivalent capacitance of the compensation capacitor array. The comparator provides a comparison signal according to whether the output voltage of the S/H circuit is positive or negative. The switch control circuit controls the equivalent capacitance of the array according to the comparison signal such that the result of the target capacitance added to the equivalent capacitance of the array gradually approximates the reference capacitance with each cycle of a clock signal.

The invention relates to a capacitance type touch control device and a sensing device thereof. The sensing device comprises a reference capacitance module, a switching module, an integrating circuit, and a control circuit, wherein the switching module is used for receiving control signals, a first reference voltage and a second reference voltage and enabling the reference capacitance module and acapacitance type touch pad to be respectively coupled with the first reference voltage and the second reference voltage according to the control signals, or enabling the reference capacitance module to be coupled to a sensing capacitor on the capacitance type touch pad. The integrating circuit is used for receiving a regulation voltage and carrying out integration on the charge difference of electric charge quantity stored by the reference capacitance module and the sensing capacitor so as to obtain integral results. When the capacitance type touch pad of the control circuit is not touched, the regulation voltage is regulated according to a voltage regulation signal generated by the integral result. According to the capacitance type touch control device and the sensing device thereof, equivalent capacitance errors generated by circuit components and wiring in the touch control device do not need to be taken into account, and therefore capacitance changes on the capacitance type touch pad can be accurately detected.

The invention relates to a multi-terminal MMC-HVDC (modular multi-level converter high voltage direct current) bipolar short-circuit fault current calculation method. The method includes the following steps that: 1) the equivalent capacitance, equivalent reactance and equivalent resistance of the fault equivalent circuit of a single-terminal MMC-HVDC system converter station are calculated; 2) the discharge current of the converter station which appears after the converter station is latched is calculated; 3) the initial solution of the discharge current of each converter station in a multi-terminal MMC-HVDC system under a condition that the discharge current of the converter station is not affected by other converter stations is calculated; 4) fault current actually passing through each direct-current line in the multi-terminal MMC-HVDC system is calculated; 5) the equivalent resistance and equivalent reactance of the actual fault equivalent circuit of the converter station at each terminal in the multi-terminal MMC-HVDC system are calculated; 6) the discharge current of the converter station at each terminal of the multi-terminal MMC-HVDC system is re-calculated; and 7) the step 4) to step 6) are repeated, and the discharge current value of the outlet of the converter station at each terminal of the multi-terminal MMC-HVDC system is calculated. The multi-terminal MMC-HVDC bipolar short-circuit fault current calculation method has high precision and speed and is of a certain guiding significance for direct current power grid planning and direct current circuit breaker selection.

The invention provides a method for detecting the electric quantity of a lithium ion battery for an electric vehicle. The method comprises obtaining a function expression of an OCV-SOC (Open Circuit Voltage and State Of Charge) curve by an interpolation method in the case of constant discharge current and setting the road conditions during usage to select a minimum error of curve reference table; measuring the OCV of the lithium ion battery under the fully-charged state and a current value under external loads, obtaining the internal resistance of the lithium ion battery through a loop current value, the load size, the load voltage and the OCV and meanwhile recording the total number of charging and discharging of the battery; collecting the working loop current of the lithium ion battery and the voltage of each end of the battery every T1 time when the lithium ion battery works, obtaining the voltage of the equivalent capacitance through the conversion according to the internal resistance, performing the difference operation on the voltage, performing the integral operation on the time through the current, calculating the ratio of the voltage and the current and obtaining the residual voltage through the comparison on a newly proposed reference curve.

The invention discloses a mixed type multi-level current converter with direct-current fault ride-through capability and a working method. The current converter is based on a dislocation stacking theory and comprises a three-phase bridge rectifier circuit; each bridge arm of the three-phase bridge rectifier circuit comprises a dislocation stacking module, a cascading double-sub-module assembly, a half-bridge sub-module assembly and an electric reactor which are cascaded to one another; when a fault occurs, a discharging process before locking of the current converter is an oscillating discharging process under known initial conditions; and after the current converter is locked, equivalent capacitance values of the bridge arms are changed, if and only if backward voltages of cascading capacitors of the bridge arms are always greater than an alternating-current line voltage amplitude value in any loop states, a short-circuiting current is reduced to zero by the inverting blocking characteristic of diodes, and the direct-current fault is eliminated. The direct-current fault is eliminated in a self-limited manner by locking the current converter, and an extra high-voltage and direct-current circuit breaker is not required. The mixed type multi-level current converter with the direct-current fault ride-through capability is suitable for a common overhead circuit, and can be used for the fields of multi-terminal direct-current network establishment, new energy grid connection, passive network power supply and the like.

The Colpitts circuit is configured so that an equivalent capacitance of the voltage-dividing first and second capacitors connected in series through the output of the transistor amplifier is variable under the condition that the ratio of the capacitance of the first capacitor to that of the second capacitor is kept unchanged at a prescribed value. The first and second capacitors are, as a whole, configured as a matrix of elemental capacitors with 2 rows and a plural number n of columns, an array of the elemental capacitors in the first row being allotted to the first capacitor and an array of the elemental capacitors in the second row being allotted to the second capacitor. Two elemental capacitors in each column j (j=1, 2, . . . n) are connected in series and the ratio of the capacitance of the elemental capacitor corresponding to the 1j element of the matrix to the capacitance of the elemental capacitor corresponding to the 2j element has the prescribed value. The Colpitts circuit further has a first switch and a second switch allotted to each of the columns. Each of the elemental capacitors allocated to the first row is connected to the control electrode of the transistor amplifier through the first switch, and the junction of the two elemental capacitors allocated to each column is connected to the output of said transistor amplifier through the second switch. The first and second switches are operated synchronously for every column.

A novel semiconductor variable capacitor is presented. The semiconductor structure is simple and is based on a semiconductor variable MOS capacitor structure suitable for integrated circuits, which has at least three terminals, one of which is used to modulate the equivalent capacitor area of the MOS structure by increasing or decreasing its DC voltage with respect to another terminal of the device, in order to change the capacitance over a wide ranges of values. Furthermore, the present invention decouples the AC signal and the DC control voltage avoiding distortion and increasing the performance of the device, such as its control characteristic. The present invention is simple and only slightly dependent on the variations due to the fabrication process. It exhibits a high value of capacitance density and, if opportunely implemented, shows a linear dependence of the capacitance value with respect to the voltage of its control terminal.

The present invention provides a coordinate calibrating method of touch control screen, wherein the method comprises the following steps: providing a display panel which comprises a plurality of display coordinates and a display coordinate value of first axis in the direction of the first axis; providing a capacitive sensor which is configured with a plurality of induction electrodes that are respectively corresponding with a plurality of capacitive coordinate values in the direction of the first axis, and is provided with a maximal capacitive coordinate value; when the capacitive sensor is touched, a plurality of digital values corresponding with each capacitive electrode are detected; multiplexing the digital value with the capacitive coordinate value corresponding with each capacitive electrode for obtaining an addition value; dividing the addition value by the maximal capacitive coordinate value for obtaining an interpolate value; and multiplexing the interpolate value with the display coordinate value of first axis for obtaining a calibration coordinate. The coordinate of edge is determined with the digital value corresponding with the equivalent capacitance induced by the edge induction electrode. The problem that the configuration of coordinate of condenser type touch control board is unmatched with the configuration of coordinate of display is settled.