CN105024681A - Touch detection circuit capable of adjusting sensitivity and range - Google Patents
Touch detection circuit capable of adjusting sensitivity and range Download PDFInfo
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- CN105024681A CN105024681A CN201510355329.4A CN201510355329A CN105024681A CN 105024681 A CN105024681 A CN 105024681A CN 201510355329 A CN201510355329 A CN 201510355329A CN 105024681 A CN105024681 A CN 105024681A
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Abstract
The invention discloses a touch detection circuit capable of adjusting sensitivity and a range. The circuit comprises a summing circuit, an integrator and a detection circuit. A touch key capacitor is connected in the summing circuit, an adjustable capacitor is connected in the detection circuit, and the summing circuit and the detection circuit are both connected with the integrator. Through arrangement of the detection circuit, capacitance of the integral term is adjustable, partial charges of the touch key capacitor can be neutralized, the output voltage of an operational amplifier is limited to a proper magnitude, and sensitivity and the range for capacitance detection can be kept.
Description
Technical field
The invention belongs to the technical field of touch key-press, particularly the control circuit of touch key-press.
Background technology
Touch key-press technology is popular gradually is in recent years the consumer electronics field of representative for mobile phone and panel computer.As man-machine interface, touch key-press is more more durable and attractive in appearance than mechanical key, and volume is also less.
The principle that realizes of touch key-press technology is the generation being judged touch event by the capacitance variations detected on button.Because the parasitic capacitance on the circuit board of different manufacturers has larger difference, touch detection circuit has different detection sensitivities and capacitance detecting scope for different circuit boards.On the other hand, because touch detection circuit needs always in running order, the design of low-power consumption seems particularly important.
Patent application 201310687548.3 discloses a kind of touch key-press chip and sensitivity correction method thereof and electronic equipment, in this application, touch key-press chip carrys out standard of compensation button activation threshold value by contact control module according to the difference of the parasitic capacitance of each passage, particularly the difference between the parasitic capacitance of each passage and external calibration electric capacity is converted into the offset of benchmark button activation threshold value, make after starting to trigger each button, the discharge and recharge time of the electric capacity of button respective channel is as far as possible consistent, namely the sensitivity of touch key-press and conforming difference is reduced.
But, in this application, by contrast and the calculating of threshold values, on hardware is formed, still belong to more complicated, need multiple induction electrode, external calibration electric capacity, cost is higher, and, this application utilizes the discharge and recharge time of electric capacity as far as possible consistent, reaches the sensitivity that reduces touch key-press and consistency difference, can not adjust for sensitivity and scope.
Summary of the invention
For solving the problem, the object of the present invention is to provide the touch detection circuit of a kind of adjustable sensitivity and scope, this circuit can adjust detection sensitivity and scope according to the size of parasitic capacitance, and power consumption is little.
For achieving the above object, technical scheme of the present invention is as follows.
The touch detection circuit of a kind of adjustable sensitivity and scope, this circuit is made up of summing circuit sum-product intergrator, it is characterized in that this circuit also includes testing circuit, described touch key-press electric capacity is connected in described summing circuit, and tunable capacitor is connected in described testing circuit; Summing circuit and testing circuit are all connected to described integrator.
Further, described summing circuit is made up of non-overlapping clock Φ 1/ Φ 2 and touch key-press electric capacity, testing circuit is made up of non-overlapping clock Φ 1/ Φ 2 and tunable capacitor, summing circuit and testing circuit are all connected to the input of integrator, control sampling item and integration item respectively by non-overlapping clock Φ 1/ Φ 2.
Further, in testing circuit, be provided with switch, described switch is connected to different voltage sources, and what described non-overlapping clock Φ 1/ Φ 2 connected is respectively by the switch that Φ 1/ Φ 2 controls.
Described different voltage source is opposite polarity voltage source.
The present invention is by the setting to testing circuit, the electric capacity of integration item is made to become adjustable, thus the Partial charge of touch key-press electric capacity can be offset, make the output voltage Vo of operational amplifier be limited in a suitable size, thus the sensitivity that detects of holding capacitor and scope.
And the present invention is only made up of simple integrator and summing circuit, testing circuit, structure is simple, easily realizes, low in energy consumption.
Accompanying drawing explanation
Fig. 1 is the circuit diagram that the present invention implements.
The Vcp exemplary waveforms figure that the institute of the present invention implementing circuit that Fig. 2 is produces.
Embodiment
In order to make object of the present invention, technical scheme and advantage clearly understand, below in conjunction with drawings and Examples, the present invention is further elaborated.Should be appreciated that specific embodiment described herein only in order to explain the present invention, be not intended to limit the present invention.
Please refer to shown in Fig. 1, the adjustable sensitivity implemented for the present invention and the touch detection circuit of scope, wherein, this circuit is made up of summing circuit sum-product intergrator, touch key-press electric capacity C1 (being generally parasitic capacitance) is connected in summing circuit, and tunable capacitor C2 is connected in testing circuit.
Summing circuit is made up of non-overlapping clock Φ 1/ Φ 2 and touch key-press electric capacity, testing circuit is made up of non-overlapping clock Φ 1/ Φ 2 and tunable capacitor, summing circuit and testing circuit are all connected to the input of integrator, control sampling item and integration item respectively by non-overlapping clock Φ 1/ Φ 2.
In testing circuit, be provided with switch, described switch is connected to different voltage sources, and what described non-overlapping clock Φ 1/ Φ 2 connected is respectively by the switch that Φ 1/ Φ 2 controls.
In FIG, non-overlapping clock Φ 1/ Φ 2 controls sampling item and integration item respectively.
(1) during Φ 2=1 at integration item, C1 and C2 all by respective charge transfer to CA, and output voltage Vo.Comparator cp compares the size of Vo and Vref, if Vo is less than Vref, then and the output Vcp=0 of comparator, otherwise Vcp=1.
(2) during Φ 1=1 sampling item, C1 is charged to it by V1.C2 is charged to it by voltage V2 or V3, and concrete condition depends on the value of Vcp, if Vcp=1, is then charged to C2 by V2, if Vcp=0, is then charged to C2 by V3.Wherein, V2 and V3 is opposite polarity voltage.The exemplary waveforms of the output Vcp of this circuit as shown in Figure 2.
The timing circuit clock number Ctk calculated between two falling pulse occurs as long as just can determine whether touch event.In general, clock number Ctk equals the ratio of voltage Vref and Vo plateau voltage.
When there being touch event to occur, the capacitance being equivalent to C1 increases, and the plateau voltage of Vo also will increase thereupon, and Ctk will reduce.If Ctk is less than the threshold value of setting, can think that touch event occurs.
C2 in Fig. 2 is tunable capacitor.User can according to the size adjustment C2 of parasitic capacitance C1 on circuit board to obtain required sensitivity and capacitance detecting scope.Specifically, when parasitic capacitance C1 is larger, can select the C2 that larger, so the electric charge of C2 can offset the Partial charge on C1, thus the plateau voltage of Vo is limited a suitable size, also just maintains sensitivity and the scope of capacitance detecting.
The present invention is by the setting to testing circuit, the electric capacity of integration item is made to become adjustable, thus the Partial charge of touch key-press electric capacity can be offset, make the output voltage Vo of operational amplifier be limited in a suitable size, thus the sensitivity that detects of holding capacitor and scope.
The present invention is only made up of simple integrator and summing circuit, testing circuit, and structure is simple, easily realizes, and low in energy consumption.
The foregoing is only preferred embodiment of the present invention, not in order to limit the present invention, all any amendments done within the spirit and principles in the present invention, equivalent replacement and improvement etc., all should be included within protection scope of the present invention.
Claims (4)
1. the touch detection circuit of an adjustable sensitivity and scope, this circuit is made up of summing circuit sum-product intergrator, it is characterized in that this circuit also includes testing circuit, described touch key-press electric capacity is connected in described summing circuit, and tunable capacitor is connected in described testing circuit; Summing circuit and testing circuit are all connected to described integrator.
2. the touch detection circuit of adjustable sensitivity as claimed in claim 1 and scope, it is characterized in that described summing circuit is made up of non-overlapping clock Φ 1/ Φ 2 and touch key-press electric capacity, testing circuit is made up of non-overlapping clock Φ 1/ Φ 2 and tunable capacitor, summing circuit and testing circuit are all connected to the input of integrator, control sampling item and integration item respectively by non-overlapping clock Φ 1/ Φ 2.
3. the touch detection circuit of adjustable sensitivity as claimed in claim 2 and scope, it is characterized in that being provided with switch in testing circuit, described switch is connected to different voltage sources, and what described non-overlapping clock Φ 1/ Φ 2 connected is respectively by the switch that Φ 1/ Φ 2 controls.
4. the touch detection circuit of adjustable sensitivity as claimed in claim 3 and scope, is characterized in that described different voltage source is opposite polarity voltage source.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510355329.4A CN105024681A (en) | 2015-06-25 | 2015-06-25 | Touch detection circuit capable of adjusting sensitivity and range |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510355329.4A CN105024681A (en) | 2015-06-25 | 2015-06-25 | Touch detection circuit capable of adjusting sensitivity and range |
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| CN105024681A true CN105024681A (en) | 2015-11-04 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN201510355329.4A Pending CN105024681A (en) | 2015-06-25 | 2015-06-25 | Touch detection circuit capable of adjusting sensitivity and range |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107508956A (en) * | 2017-08-23 | 2017-12-22 | 重庆哈迪斯科技有限公司 | A kind of mobile phone key sensibility testing arrangement |
| CN108886361A (en) * | 2018-06-21 | 2018-11-23 | 深圳市汇顶科技股份有限公司 | A kind of key substrate removing method, capacitance key detection circuit and intelligent terminal |
| CN109039321A (en) * | 2018-10-15 | 2018-12-18 | 湖南品腾电子科技有限公司 | A kind of touch button device and sensitivity automatic adjusting method |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102109938A (en) * | 2009-12-28 | 2011-06-29 | 奇景光电股份有限公司 | Touch panel |
| CN102200869A (en) * | 2010-03-24 | 2011-09-28 | 盛群半导体股份有限公司 | Capacitance type touch control device and sensing device thereof |
| US20110279407A1 (en) * | 2010-05-13 | 2011-11-17 | Silicon Works Co., Ltd. | Circuit for processing touch line signal of touch screen |
| US8446158B1 (en) * | 2007-11-09 | 2013-05-21 | Cypress Semiconductor Corporation | Compensation for parasitic capacitance of a capacitive sensor |
| CN103487662A (en) * | 2013-07-24 | 2014-01-01 | 泰凌微电子（上海）有限公司 | Capacitance detection circuit |
| CN103618553A (en) * | 2013-11-26 | 2014-03-05 | 苏州贝克微电子有限公司 | Improved complete-accurate triangle integral modulator |
-
2015
- 2015-06-25 CN CN201510355329.4A patent/CN105024681A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8446158B1 (en) * | 2007-11-09 | 2013-05-21 | Cypress Semiconductor Corporation | Compensation for parasitic capacitance of a capacitive sensor |
| CN102109938A (en) * | 2009-12-28 | 2011-06-29 | 奇景光电股份有限公司 | Touch panel |
| CN102200869A (en) * | 2010-03-24 | 2011-09-28 | 盛群半导体股份有限公司 | Capacitance type touch control device and sensing device thereof |
| US20110279407A1 (en) * | 2010-05-13 | 2011-11-17 | Silicon Works Co., Ltd. | Circuit for processing touch line signal of touch screen |
| CN103487662A (en) * | 2013-07-24 | 2014-01-01 | 泰凌微电子（上海）有限公司 | Capacitance detection circuit |
| CN103618553A (en) * | 2013-11-26 | 2014-03-05 | 苏州贝克微电子有限公司 | Improved complete-accurate triangle integral modulator |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107508956A (en) * | 2017-08-23 | 2017-12-22 | 重庆哈迪斯科技有限公司 | A kind of mobile phone key sensibility testing arrangement |
| CN108886361A (en) * | 2018-06-21 | 2018-11-23 | 深圳市汇顶科技股份有限公司 | A kind of key substrate removing method, capacitance key detection circuit and intelligent terminal |
| WO2019241968A1 (en) * | 2018-06-21 | 2019-12-26 | 深圳市汇顶科技股份有限公司 | Method for eliminating button base, capacitive button detection circuit and intelligent terminal |
| CN108886361B (en) * | 2018-06-21 | 2022-04-12 | 深圳市汇顶科技股份有限公司 | Key substrate eliminating method, capacitive key detection circuit and intelligent terminal |
| CN109039321A (en) * | 2018-10-15 | 2018-12-18 | 湖南品腾电子科技有限公司 | A kind of touch button device and sensitivity automatic adjusting method |
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Application publication date: 20151104 |
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