CN100410862C - Resistance touch screen measuring system - Google Patents
Resistance touch screen measuring system Download PDFInfo
- Publication number
- CN100410862C CN100410862C CNB2005101184130A CN200510118413A CN100410862C CN 100410862 C CN100410862 C CN 100410862C CN B2005101184130 A CNB2005101184130 A CN B2005101184130A CN 200510118413 A CN200510118413 A CN 200510118413A CN 100410862 C CN100410862 C CN 100410862C
- Authority
- CN
- China
- Prior art keywords
- switch
- coupled
- resistance
- voltage
- touch screen
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Images
Abstract
A measurement system of contact controlled screen in resistance type comprises the first switch coupled with the first power supply, the second switch coupled with the second power supply, the first resistance coupled between two said switches in series way, comparator coupled with the first switch, successive-approximation register coupled with said comparator and artificial circuit. It is featured as converting voltage generated from contact controlled screen to be a digital signal by regulating output voltage of artificial circuit continuously with said comparator and artificial circuit.
Description
Technical field
The present invention relates to a kind of screen measuring system, particularly a kind of resistance touch screen measuring system.
Background technology
The resistance touch screen measuring system that existing screen was equipped with mainly is to be main flow in development with two kinds of patterns, and wherein these two kinds of patterns are to be single-ended mode (Single-ended Mode) and differential mode (Differential Mode).
See also Fig. 1, it is the schematic equivalent circuit of the resistance touch screen measuring system of use differential mode.And please consult Fig. 2 simultaneously, it is started to write and a little corresponds to the coordinate time of a Touch Screen, the on off state synoptic diagram of each assembly to obtain one measuring one first coordinate element and one second coordinate element for the resistance touch screen measuring system 100 of differential mode shown in Figure 1.Wherein, this coordinate is the two-dimensional coordinate that is used to represent the planimetric position for, therefore the first coordinate element that this coordinate comprised is meant the X coordinate (Xposition) that this coordinate comprises, and the second coordinate element that this coordinate comprised is meant the coordinate (Y position) that this coordinate comprises.Resistance touch screen measuring system 100 is to comprise a sense of touch system 101, one analog/digital converter 103, and a Touch Screen 120, be arranged on the sense of touch system 101 being used for receiving the artificial signal that touching was produced, and this signal is passed to sense of touch system 101.(among Fig. 1, Touch Screen 120 is not contained in sense of touch system 101, just overlaps to some extent with sense of touch system 101.) resistance touch screen measuring system 100 and comprise one first power supply 151 and a second source 153 in addition, be used to provide the required bias voltage of sense of touch system 101.Sense of touch system 101 comprises one first switching transistor 105, one second switch transistor 107, one the 3rd switching transistor 109, one the 4th switching transistor 111, one first resistance 113, be coupled in one first voltage output end 121 with first switching transistor 105, one second resistance 115, be coupled in one second voltage output end 123 with second switch transistor 107, one the 3rd resistance 117, be coupled in a tertiary voltage output terminal 125 with the 3rd switching transistor 109, one the 4th resistance 119, be coupled in one the 4th voltage output end 127 with the 4th switching transistor 111, and one start to write a little 129, with first resistance 113, second resistance 115, the 3rd resistance 117,119 couplings of the 4th resistance.Analog/digital converter 103 is to comprise an input end of analog signal 131, be coupled in first voltage output end 121 via a switch 171, and be coupled in tertiary voltage output terminal 125 via a switch 173, one reference voltage upper bound input end 133, be coupled in first voltage output end 121 via a switch 175, and be coupled in tertiary voltage output terminal 125 via a switch 177, one reference voltage lower bound input end 135, be coupled in second voltage output end 123 via a switch 179, and be coupled in the 4th voltage output end 127, an and digital signal output end 137 via a switch 181.Wherein first resistance 113 and second resistance 115 were to be same resistance originally, and the 3rd resistance 117 and the 4th resistance 119 were to be same resistance originally, but because the artificial touching that on Touch Screen 120, is produced, therefore in sense of touch system 101, correspond to starting to write a little of this touch position and produced a corresponding signal on 129, and be equivalent to and separate with second resistance 115 for first resistance 113 of same resistance originally, and be equivalent to and separate with the 4th resistance 119 for the 3rd resistance 117 of same resistance originally.
When measurement starts to write a little 129 during with respect to the first coordinate element of the coordinate of Touch Screen 120, open the 3rd switching transistor 109 and the 4th switching transistor 111, and close first switching transistor 105 and second switch transistor 107, therefore a little 129 will produce one first output voltage starting to write, and this first output voltage will be by the path of first resistance 113 in first voltage output end, 121 generations, one second output voltage.The switch 171 that be coupled between the input end of analog signal 131 and first voltage output end 121 this moment is unlocked, and the switch 173 that is coupled between input end of analog signal 131 and the tertiary voltage output terminal 125 is closed, so this second output voltage can input in the analog/digital converter 103 by input end of analog signal 131.Moreover, the switch 177 that be coupled between reference voltage upper bound input end 133 and the tertiary voltage output terminal 125 this moment is unlocked, and the switch 175 that is coupled between the reference voltage upper bound input end 133 and first voltage output end 121 is closed, therefore the voltage of tertiary voltage output terminal 125 can input in the analog/digital converter 103 via reference voltage upper bound input end 133, and be regarded as the upper bound of a reference voltage.And the switch 181 that be coupled between reference voltage lower bound input end 135 and the 4th voltage output end 127 this moment is unlocked, and the switch 179 that is coupled between the reference voltage lower bound input end 135 and second voltage output end 123 is closed, and therefore the voltage of the 4th voltage output end 127 can input in the analog/digital converter 103 via reference voltage lower bound input end 135.By the function of analog-digital converter 135 itself, this second output voltage that is transfused to can be converted to corresponding digital signal representing the first coordinate element of this coordinate, and via digital signal output end 137 outputs.
When measurement starts to write a little 129 when corresponding to the second coordinate element of coordinate of Touch Screen 120, open first switching transistor 105 and second switch transistor 107, and close the 3rd switching transistor 109 and the 4th switching transistor 111, therefore a little 129 will produce one the 3rd output voltage in starting to write, and the 3rd output voltage will produce one the 4th output voltage in tertiary voltage output terminal 125 by the path of the 3rd resistance 117.The switch 173 that be coupled between input end of analog signal 131 and the tertiary voltage output terminal 125 this moment is unlocked, and the switch 171 that is coupled between the input end of analog signal 131 and first voltage output end 121 is closed, so the 4th output voltage can input in the analog/digital converter 103 by input end of analog signal 131.Moreover, the switch 177 that be coupled between reference voltage upper bound input end 133 and the tertiary voltage output terminal 125 this moment is closed, and the switch 175 that is coupled between the reference voltage upper bound input end 133 and first voltage output end 121 is unlocked, therefore the voltage of first voltage output end 121 can input in the analog/digital converter 103 via reference voltage upper bound input end 133, and be regarded as the upper bound of a reference voltage.And the switch 181 that be coupled between reference voltage lower bound input end 135 and the 4th voltage output end 127 this moment is closed, and the switch 179 that is coupled between the reference voltage lower bound input end 135 and second voltage output end 123 is unlocked, therefore the voltage of second voltage output end 123 can input in the analog/digital converter 103 via reference voltage lower bound input end 135, and be regarded as the lower bound of a reference voltage.By the function of analog-digital converter 135 itself, the 4th output voltage that is transfused to can be converted to corresponding digital signal representing the second coordinate element of this coordinate, and via digital signal output end 137 outputs.
Yet, start to write a little 129 when corresponding to the first coordinate element of coordinate of Touch Screen 120 in measurement, because after this second output voltage is input to analog/digital converter 103, reference voltage upper bound input end 133 still need continue to import the voltage from tertiary voltage output terminal 125, and reference voltage lower bound input end 135 still need continue to import the voltage from the 4th voltage output end 127, therefore the 3rd switching transistor 109 and the 4th switching transistor 111 cannot be closed, otherwise analog/digital converter 103 will lose and be used for being used as the reference voltage of level and produce bigger error.This phenomenon will cause the prolongation of the 3rd switching transistor 109 and 111 running times of the 4th switching transistor, the equivalent resistance of adding resistance touch screen measuring system 100 is about 0.1 to 0.9Kohm, therefore uses the resistance touch screen measuring system 100 of differential mode will have bigger power consumption.Moreover starting to write a little when measurement 129 also has similar phenomenon and bigger equally power consumption when corresponding to the second coordinate element of coordinate of Touch Screen 120.
See also Fig. 3, it is the schematic equivalent circuit of the resistance touch screen measuring system of use single-ended mode.And please consult Fig. 4 simultaneously, it corresponds to one of a Touch Screen start to write a little coordinate time, the on off state synoptic diagram of each assembly to obtain one for the resistance touch screen measuring system 200 of single-ended mode shown in Figure 3 measuring one first coordinate element and one second coordinate element.Wherein, this coordinate is identical with the coordinate described in Fig. 1, it is the two-dimensional coordinate that is used to represent the planimetric position for, therefore the first coordinate element that this coordinate comprised is meant the X coordinate (X position) that this coordinate comprises, and the second coordinate element that this coordinate comprised is meant the Y coordinate (Y position) that this coordinate comprises.Resistance touch screen system 200 comprises a sense of touch system 201, one analog/digital converter 203, and a Touch Screen 220, be arranged on this sense of touch system 201 being used for receiving the artificial signal that touching was produced, and this signal is passed to sense of touch system 201.(among Fig. 3, Touch Screen 220 is not contained in sense of touch system 201, just overlaps to some extent with sense of touch system 201.) resistance touch screen measuring system 200 and comprise one first power supply 251 and a second source 253 in addition, be used to provide the required bias voltage of sense of touch system 201.Sense of touch system 201 comprises one first switching transistor 205, one second switch transistor 207, one the 3rd switching transistor 209, one the 4th switching transistor 211, one first resistance 213, be coupled in one first voltage output end 221 with first switching transistor 205, one second resistance 215, be coupled in one second voltage output end 223 with second switch transistor 207, one the 3rd resistance 217, be coupled in a tertiary voltage output terminal 225 with the 3rd switching transistor 209, one the 4th resistance 219, be coupled in one the 4th voltage output end 227 with the 4th switching transistor 211, and one start to write a little 229, with first resistance 213, second resistance 215, the 3rd resistance 217,219 couplings of the 4th resistance.Analog/digital converter 203 is to comprise an input end of analog signal 231, be coupled in first voltage output end 221 via a switch 271, and be coupled in tertiary voltage output terminal 225 via a switch 273, one reference voltage upper bound input end 233, be coupled in a direct current voltage source V DD, one reference voltage lower bound input end 235 is coupled in earth terminal GND, and a digital signal output end 237.Wherein first resistance 213 and second resistance 215 were to be same resistance originally, and the 3rd resistance 217 and the 4th resistance 219 were to be same resistance originally, but because the artificial touching that on Touch Screen 220, is produced, therefore in sense of touch system 201, correspond to starting to write a little of this touch position and produced a corresponding signal on 229, and be equivalent to and separate with second resistance 215 for first resistance 213 of same resistance originally, and be equivalent to and separate with the 4th resistance 219 for the 3rd resistance 217 of same resistance originally.
When measurement starts to write a little 229 when corresponding to the first coordinate element of coordinate of Touch Screen 220, open the 3rd switching transistor 209 and the 4th switching transistor 211, and close first switching transistor 205 and second switch transistor 207, therefore a little 229 will produce one first output voltage starting to write, and this first output voltage will be by the path of first resistance 213 in first voltage output end, 221 generations, one second output voltage.The switch 271 that be coupled between the input end of analog signal 231 and first voltage output end 221 this moment is unlocked, and the switch 273 that is coupled between input end of analog signal 231 and the tertiary voltage output terminal 225 is closed, so this second output voltage can input in the analog/digital converter 203 by input end of analog signal 231.Moreover the direct voltage source VDD that be input into reference voltage upper bound input end 233 this moment is regarded as the upper bound of a reference voltage, and the earth terminal GND that is coupled in reference voltage lower bound input end 235 is regarded as the lower bound of a reference voltage.By the function of analog-digital converter 235 itself, this second output voltage that is transfused to can be converted to corresponding digital signal representing the first coordinate element of this coordinate, and via digital signal output end 237 outputs.
When measurement starts to write a little 229 when corresponding to the second coordinate element of coordinate of Touch Screen 220, open first switching transistor 205 and second switch transistor 207, and close the 3rd switching transistor 209 and the 4th switching transistor 211, therefore a little 229 will produce one the 3rd output voltage starting to write, and the 3rd output voltage will be by the path of the 3rd resistance 217 at tertiary voltage output terminal 225 generations one the 4th output voltage.The switch 273 that be coupled between input end of analog signal 231 and the tertiary voltage output terminal 225 this moment is unlocked, and the switch 271 that is coupled between the input end of analog signal 231 and first voltage output end 221 is closed, so the 4th output voltage can input in the analog/digital converter 203 by input end of analog signal 231.Moreover the direct voltage source VDD that is transfused to reference voltage upper bound input end 233 is regarded as the upper bound of a reference voltage, and the earth terminal GND that is coupled in reference voltage lower bound input end 235 is regarded as the lower bound of a reference voltage.By the function of analog-digital converter 235 itself, the 4th output voltage that is transfused to can be converted to corresponding digital signal representing the second coordinate element of this coordinate, and via digital signal output end 237 outputs.
When measurement starts to write a little 229 when corresponding to the first coordinate element of coordinate of Touch Screen 220, after this second output voltage input analog/digital converter 203, analog/digital converter 203 has needed to continue the voltage of input tertiary voltage output terminal 225 and the 4th voltage output end 227 unlike analog/digital converter 103, therefore aspect power consumption, it is less that the power that the resistance touch screen measuring system 200 of use single-ended mode uses the resistance touch screen measuring system 100 of differential mode to be consumed comes.Yet because the analog/digital converter 203 employed reference voltage upper bounds are direct voltage source VDD, and analog/digital converter 203 employed reference voltage lower bounds are earth terminal GND, the virtual voltage of adding the first voltage output point 221 is VDD-Vsd, and the virtual voltage of the second voltage output point 223 is GND+Vds, therefore the bias voltage of analog/digital converter 203 all can produce bigger error with gain, wherein Vsd is the source electrode of first switching transistor 205 voltage difference to drain electrode, Vds is draining to the voltage difference of source electrode for second switch transistor 207, and the size of Vsd and Vds all with the operating voltage of switching transistor, temperature, and breadth length ratio is relevant, so the change of Vsd and Vds is bigger.Moreover, compare with analog/digital converter 203, directly use tertiary voltage output terminal 125 and the 4th voltage output end 127 all accurate with gain, and start to write a little when measurement and 229 also to have identical phenomenon when corresponding to the second coordinate element of coordinate of Touch Screen 220 than analog/digital converter 203 as the bias voltage of the analog/digital converter 103 of reference voltage.
Summary of the invention
Therefore, the present invention provides a kind of resistance touch screen measuring system, with the shortcoming of the resistance touch screen measuring system that improves described use single-ended mode of prior art or differential mode.
The invention provides a kind of resistance touch screen measuring system, one first switch, its first end are to be coupled in one first power supply; One second switch, one end are to be coupled in a second source; One the 3rd switch, its first end are to be coupled in this first power supply; One the 4th switch, the one end be coupled in this second source; One first resistance is coupled between this first switch and this second switch in the mode of connecting; One the 3rd resistance is coupled between the 3rd switch and the 4th switch in the mode of connecting; One comparer, its first input end are second ends that is coupled in this first switch; One the 9th switch is coupled between second end of the first input end of this comparer and this first switch; The tenth switch is coupled between second end of the first input end of this comparer and the 3rd switch, a successive approximation register, and its input end is the output terminal that is coupled in this comparer; And an artificial circuit, it comprises: one the 5th resistance; One the 5th switch, its first end are to be coupled in this first power supply, and second end is second input end that is coupled in the 5th resistance and this comparer; One the 6th switch is coupled between the 5th resistance and this second source; One group of minion is closed, and is coupled between the 5th resistance and this first power supply in the mode that is parallel to the 5th switch, and this control end of organizing each switch of minion pass is an output terminal that is coupled in one group of output terminal of this successive approximation register; One group of octavo is closed, be coupled between the 5th resistance and this second source in the mode that is parallel to the 6th switch, this control end of organizing each switch of octavo pass is an output terminal that is coupled in this group output terminal of this successive approximation register, wherein, this artificial circuit comprises one group of phase inverter in addition, and each phase inverter is to be coupled between the output terminal of this group output terminal of this control end of organizing the switch that minion closes and this successive approximation register.
Description of drawings
Fig. 1 is the schematic equivalent circuit of the resistance touch screen measuring system of use differential mode.
Fig. 2 starts to write and a little corresponds to the coordinate time of a Touch Screen, the on off state synoptic diagram of each assembly to obtain one measuring one first coordinate element and one second coordinate element for the resistance touch screen measuring system of differential mode shown in Figure 1.
Fig. 3 is the schematic equivalent circuit of the resistance touch screen measuring system of use single-ended mode.
Fig. 4 corresponds to one of a Touch Screen start to write a little coordinate time, the on off state synoptic diagram of each assembly to obtain one for the resistance touch screen measuring system of single-ended mode shown in Figure 3 measuring one first coordinate element and one second coordinate element.
Fig. 5 is the schematic equivalent circuit of the sense of touch system that resistance touch screen measuring system of the present invention comprised.
Fig. 6 is the schematic equivalent circuit of the signal generation system that resistance touch screen measuring system of the present invention comprised.
Fig. 7 be the resistance touch screen measuring system of Fig. 5 and invention shown in Figure 6 when phase one of the present invention, the on off state synoptic diagram of each assembly.
Fig. 8 is the schematic equivalent circuit of the artificial circuit that resistance touch screen measuring system of the present invention comprised.
Fig. 9 is the synoptic diagram of the analog/digital converter that resistance touch screen measuring system of the present invention comprised.
Figure 10 for the resistance touch screen measuring system of Fig. 8 and invention shown in Figure 9 when carrying out subordinate phase of the present invention, the on off state synoptic diagram of each assembly.
The reference numeral explanation
Resistance touch screen measuring system 100,200
Sense of touch system 101,201,301
Analog/digital converter 103,203,403
Switching transistor 105,107,109,111,205,207,
209、211、305、307、309、311、
339、341、343、345、439、441、
443、445
Resistance 113,115,117,119,213,215,
217、219、313、315、317、319、
337、437
Voltage output end 121,123,125,127,221,223,
225、227、321、323、325、327、
347、447、449
Start to write a little 129,229,329
Input end of analog signal 131,231,455
Reference voltage upper bound input end 133,233,457
Reference voltage lower bound input end 135,235,459
Output terminal 137,237,361,461
Voltage source 151,153,251,253,351,353
Artificial circuit 331,431
Signal generation system 303
Comparer 333
Gradually approximate register 335
Touch Screen 120,220,320
Trigger 363,463
Switch 171,173,175,177,179,181,
271、273、371、373、471、473
Embodiment
The running of resistance touch screen measuring system of the present invention is mainly to be divided into a phase one and a subordinate phase, in this phase one, will produce the start to write digital signal of the second coordinate element of the coordinate that a little corresponds to Touch Screen of the digital signal of one group of first coordinate element that detects the coordinate that a little corresponds to Touch Screen of starting to write and one group of detection, and in this subordinate phase with these two groups of digital signals to control the on off state of two groups of switching transistors separately, and then when the different coordinate element of point coordinate is started to write in measurement, make these two groups of two output voltages that switching transistor produced form a reference voltage higher limit and a reference voltage lower limit, and import in the analog/digital converter, measure the first coordinate element and the second coordinate element of resistance touch screen measuring system of the present invention this point coordinate of starting to write when other of touching Touch Screen started to write with the function of using this analog/digital converter, in other words, not existing together of the operation maximum of the principle of this subordinate phase and single-ended mode is in advance the error that voltage difference caused of switching transistor itself being offseted, therefore error as shown in Figure 3 can be do not produced, but but the less power consumption the same can be reached with the described resistance touch screen measuring system of Fig. 3 200.Wherein, Fig. 5, Fig. 6, Fig. 7 is described is to be relevant to the above-described phase one, and Fig. 5, Fig. 8, Fig. 9 is described is to be relevant to above-described subordinate phase.
Please consult Fig. 5, Fig. 6 and Fig. 7 simultaneously.Fig. 5 is the schematic equivalent circuit of the sense of touch system 301 that resistance touch screen measuring system of the present invention comprised.Fig. 6 is the schematic equivalent circuit of the signal generation system 303 that resistance touch screen measuring system of the present invention comprised.Fig. 7 is Fig. 5 and resistance touch screen measuring system of the present invention shown in Figure 6 when phase one of the present invention, the on off state synoptic diagram of each assembly.Resistance touch screen measuring system of the present invention also comprises one first power supply 351 and a second source 353 in addition, and diagram is arranged all in Fig. 5 and Fig. 6, and comprise a Touch Screen 320 in addition, be arranged on the sense of touch system 301 being used for receiving the artificial signal that touching was produced, and this signal is passed to sense of touch system 301.(among Fig. 5, Touch Screen 320 is not contained in sense of touch system 301, just overlaps to some extent with sense of touch system 301.) sense of touch system 301 comprises one first switching transistor 305, its first end system is coupled in first power supply 351, one second switch transistor 307, its first end is to be coupled in second source 353, one the 3rd switching transistor 309, its first end is to be coupled in first power supply 353, one the 4th switching transistor 311, its first end is to be coupled in second source 353, one first resistance 313, be coupled in one first voltage output end 321 with first switching transistor 305, one second resistance 315, be coupled in one second voltage output end 323, the 3rd resistance 317 with second switch transistor 307, be coupled in a tertiary voltage output terminal 325 with the 3rd switching transistor 309, and one the 4th resistance 319, be coupled in one the 4th voltage output end 327 with the 4th switching transistor 311, and first resistance 313 and second resistance 315 is to be same resistance originally, the 3rd resistance 317 is to be same resistance with the 4th resistance 319 scripts.Start to write a little 329 when being triggered when corresponding to one of Touch Screen 320 in the sense of touch system 301, originally belong to first resistance 313 of same resistance and second resistance 315 by temporary transient separating, and originally belong to the 3rd resistance 317 of same resistance and the 4th resistance 319 also by temporary transient separating, and be equivalent to the schematic equivalent circuit of sense of touch circuit 301 shown in Figure 5.As shown in Figure 5, start to write a little 329 the time when triggering in order to measure a digital signal, starting to write a little 329 is coupled in first resistance 313, second resistance 315, the 3rd resistance 317, and the 4th resistance 319.Signal generation system 303 is to comprise an artificial circuit 331, one comparer 333, its first input end is coupled in first voltage output end 321 via a switch 371, and be coupled in second voltage output end 325 via a switch 373, and its second input end is coupled in artificial circuit 331, and successive approximation register (successive-approximation register, SAR) 335 that comprise an output terminal 361.Artificial circuit 331 is to comprise one the 5th resistance 337, one the 5th voltage output end 347, be coupled in second input end of the 5th resistance 337 and comparer 333, one the 5th switching transistor 339, its first end is coupled in first power supply 351, and its second end is coupled in the 5th voltage output end 347, one the 6th switching transistor 341, be coupled between the 5th resistance 337 and the second source 353, one group of minion is closed transistor 343, be coupled between the 5th voltage output end 347 and first power supply 351 in the mode that is parallel to the 5th switching transistor 339, one group of octavo is closed transistor 345, be coupled between the 5th resistance 337 and the second source 353 in the mode that is parallel to the 6th switching transistor 341, and be coupled in this and organize minion and close transistor 339 and organize one group of trigger 363 of octavo pass transistor 341 with this.This control end of organizing each switching transistor of minion pass transistor 343 is an output terminal that is coupled in one group of output terminal of successive approximation register 335, and the control end of each switching transistor of this group octavo pass transistor 345 is output terminals that are coupled in this group output terminal of successive approximation register 335.This organizes minion, and to close each switching transistor that transistor 343 comprised be to organize octavo with this to close each switching transistor that transistor 345 comprised corresponding one by one.This group trigger 363 is to be used for transmitting signal that this group output terminal of successive approximation register 335 sent closes transistor 343 to each minion control end.
Detect and to start to write a little 329 when corresponding to the digital signal of the first coordinate element of coordinate of Touch Screen 320 to obtain one group when carrying out the phase one of the present invention, open the 3rd switching transistor 325 and the 4th switching transistor 327, and close first switching transistor 321 and second switch transistor 323, so tertiary voltage output point 325 will produce an output voltage.The switch 373 that be coupled between tertiary voltage output point 325 and the comparer 333 this moment is to be opening, and the switch 371 that is coupled between the first voltage output point 321 and the comparer 333 is to be closed condition, so this output voltage just can input in the first input end of comparer 333 by this.At this moment, because the 5th voltage output end 347 does not have any voltage to produce, therefore second output terminal of comparer 333 does not also have any voltage input yet, is voltage greater than second input end so comparer 333 will export a signal with the voltage of representing present its first input end.After one input end of successive approximation register 335 has received this signal of comparer 333 outputs, being coupled in this at it organizes minion and closes transistor 343 and organize octavo with this and close 345 transistorized each input end and import a control signal one by one, organize minion and close transistor 343 and organize the on off state that octavo is closed each switching transistor in the transistor 345 to control this, and should group minion pass transistor 343 be for identical with this on off state of organizing corresponding two switching transistors in the transistor 345 of octavo pass with this.Successive approximation register 335 also determines this to organize minion with each control signal of input one by one to close transistor 343 and organize octavo with this and close switching transistor number of unlatching in the transistor 345 and be controlled at the magnitude of voltage that the 5th voltage output end 347 is produced, make this magnitude of voltage approach the voltage of the first input end that is input into comparer 333 as far as possible, even also this magnitude of voltage approaches this output voltage that tertiary voltage output terminal 325 is produced as far as possible.Through one by one behind each oxide-semiconductor control transistors input control signal, the voltage that can make voltage that tertiary voltage output terminal 325 is produced and the 5th voltage output end 347 be produced is almost equal, successive approximation register 335 will write down corresponding to this and organize the set of number signal that minion is closed transistor 343 and octavo pass transistor 345 this moment, and will organize output terminal 361 output of digital signal in successive approximation register 335, be used for being used as the detection 329 one first group of digital signal of the first coordinate element that correspond to the coordinate of Touch Screen 320 of starting to write a little will organize digital signal.After this first group of digital signal of output, the switch that is coupled between the first input end of tertiary voltage output terminal 325 and comparer 333 cuts out, detect 329 steps of digital signal of the second coordinate element that correspond to the coordinate of Touch Screen 320 of starting to write a little to prepare to obtain one group.
Detect and to start to write a little 329 when corresponding to the digital signal of the second coordinate element of coordinate of Touch Screen 320 to obtain one group when carrying out the phase one of the present invention, close the 3rd switching transistor 325 and the 4th switching transistor 327, and open first switching transistor 321 and second switch transistor 323, therefore the first voltage output point 321 will produce an output voltage.The switch 373 that be coupled between tertiary voltage output point 325 and the comparer 333 this moment is to be closed condition, and the first voltage output point 321 and the switch 371 between the comparer 333 of coupling are to be opening, so this output voltage just can input in the first input end of comparer 333 by this.At this moment, because the 5th voltage output end 347 does not have any voltage to produce, therefore second input end of comparer 333 does not also have any voltage input yet, is voltage greater than its second input end so comparer 333 will export a signal with the voltage of representing present its first input end.After one input end of successive approximation register 335 has received this signal of comparer 333 outputs, being coupled in this in it organizes minion and closes transistor 343 and organize octavo with this and close 345 transistorized each input end and import a control signal one by one, organize minion and close transistor 343 and organize the on off state that octavo is closed each switching transistor in the transistor 345 to control this, and should group minion pass transistor 343 be for identical with this on off state of organizing corresponding two switching transistors in the transistor 345 of octavo pass with this.Successive approximation register 335 also determines this to organize minion with each control signal of input one by one to close transistor 343 and organize octavo with this and close switching transistor number of unlatching in the transistor 345 and be controlled in the magnitude of voltage that the 5th voltage output end 347 is produced, make this magnitude of voltage approach the voltage of the first input end that is input into comparer 333 as far as possible, even also this magnitude of voltage approaches this output voltage that first voltage output end 321 is produced as far as possible.The voltage that voltage that the voltage output end 321 of winning produced and the 5th voltage output end 347 are produced is almost equal, successive approximation register 335 will write down corresponding to this and organize the set of number signal that minion is closed transistor 343 and octavo pass transistor 345 this moment, and will organize output terminal 361 output of digital signal in successive approximation register 335, be used for being used as start to write a little one second group of digital signal of the second coordinate element of 329 coordinate of detection will organize digital signal.After this second group of digital signal of output, the switch that is coupled between the first input end of first voltage output end 321 and comparer 333 cuts out, carry out subordinate phase of the present invention with preparation.Because after this first group of digital signal of output or this second group of digital signal, just can close the 3rd switching transistor 309 and the 4th switching transistor 311 at once or close first switching transistor 305 and second switch 307, therefore can reduce the consumed power of switching transistor as using single-ended mode.
The breadth length ratio of the temperature the when Vds of the described switching transistor of Fig. 3 or Vsd very easily are subjected to operating, operating voltage and switching transistor itself is relevant.In Fig. 5, this organizes minion pass transistor 343 is in parallel in almost adjacent mode with this each switching transistor of organizing in the transistor 345 of octavo pass, therefore can suppose that each adjacent switching transistor is to operate under same temperature.This each switching transistor of organizing minion pass transistor 343 is all to be coupled in first power supply 351, therefore each switching transistor of this group minion pass transistor 343 is all operated under same operating voltage, and each switching transistor that this group octavo is closed transistor 345 is all to be coupled in second source 353, and therefore each switching transistor of this group octavo pass transistor 345 is also operated under same operating voltage.After the different factor of each switching transistor such as temperature and operating voltage removed, just can control the size of Vds or Vsd with the breadth length ratio of switching transistor, yet because this length of organizing each switching transistor in the transistor 343 of minion pass is all identical, and the length that should organize each switching transistor in the transistor 345 of octavo pass is also identical, so width sum of a switching transistor that the needs consideration is unlocked, can effectively control the size of Vds or Vsd, also the number of the switching transistor that can be unlocked by control reaches the purpose of the voltage swing that control the 5th voltage output end 347 exported, and and then at two input terminal voltages of comparer 333 when equating, in the mode that is digital signal with each transistorized switch state, obtain measuring the 329 needed two groups of digital signals of two coordinate elements that correspond to the coordinate of Touch Screen 320 of starting to write a little.
Please consult Fig. 5, Fig. 8, Fig. 9 and Figure 10 simultaneously.Fig. 8 is the schematic equivalent circuit of the artificial circuit 431 that resistance touch screen measuring system of the present invention comprised.Fig. 9 is the synoptic diagram of the analog/digital converter 403 that resistance touch screen measuring system of the present invention comprised.Figure 10 for the resistance touch screen measuring system of Fig. 8 and invention shown in Figure 9 when carrying out subordinate phase of the present invention, the on off state synoptic diagram of each assembly.Artificial circuit 431 is to comprise one the 5th resistance 437, one the 5th voltage output end 447, be coupled in first end of the 5th resistance 437, one the 6th voltage output end 449, be coupled in second end of the 5th resistance 437, one the 5th switching transistor 439, be coupled between first power supply 351 and the 5th voltage output end 447, one the 6th switching transistor 441, be coupled between second source 353 and the 6th voltage output end 449, one group of minion is closed transistor 443, be coupled between first power supply 351 and the 5th voltage output end 447 in the mode that is parallel to the 5th switching transistor 439, one group of octavo is closed transistor 445, be coupled between second source 353 and the 6th voltage output end 449 in the mode that is parallel to the 6th switching transistor 441, and be coupled in this and organize minion and close transistor 439 and organize one group of trigger 463 of octavo pass transistor 441 with this.This control end of organizing each switching transistor of minion pass transistor 443 is an output terminal that is coupled in one group of control signal, and the control end of each switching transistor of this group octavo pass transistor 445 is output terminals that are coupled in this group control signal.This group control signal be for successive approximation register among Fig. 6 435 exported be used for measuring start to write a little 329 correspond to Touch Screen 320 coordinate the first coordinate element this first group of digital signal or be used for measuring 329 these the second group of digital signal of the second coordinate element that correspond to the coordinate of Touch Screen 320 of starting to write a little.This organizes minion, and to close each switching transistor that transistor 443 comprised be to organize octavo with this to close each switching transistor that transistor 445 comprised corresponding one by one.This group trigger 463 is to be used for transmitting successive approximation register shown in Figure 6 335 is closed transistor 443 to each minion in this group digital signal of one group output terminal output control end.Analog/digital converter 403 is to comprise an input end of analog signal 455, be coupled in a switch 471 with first voltage output end 321, and be coupled in a switch 473 with tertiary voltage output terminal 325, one reference voltage upper bound input end 457, be coupled in the 5th voltage output end 447, one reference voltage lower bound input end 459 is coupled in the 6th voltage output end 449, and a digital signal output end 461.
Start to write a little 329 when corresponding to the first coordinate element that coordinate was comprised of Touch Screen 320 when carrying out subordinate phase of the present invention with measurement, open the 3rd switching transistor 309 and the 4th switching transistor 311, and close first switching transistor 305 and second switch transistor 307, therefore produce an output voltage at first voltage output end 321.The switch 471 that be coupled between the input end of analog signal 455 of first voltage output end 321 and analog/digital converter 403 this moment is to be opening, and the switch 473 that is coupled between the input end of analog signal 455 of tertiary voltage output terminal 325 and analog/digital converter 403 is to be closed condition, so this output voltage can be directly inputted into input end of analog signal 455.At this moment, organize minion and close the on off state that transistor 439 and this one group of control signal organizing the control end of octavo pass transistor 441 are controlled each switching transistor by being coupled in this, so that the 5th voltage output end 447 produce one near but greater than the upper voltage limit of this output voltage, and make the 6th voltage output end 449 produce one near but less than the lower voltage limit of this output voltage, wherein this group control signal is to be used for measuring 329 these the first group of digital signal of the first coordinate element that correspond to the coordinate of Touch Screen 320 of starting to write a little for what successive approximation register 335 in the phase one of the present invention produced.This upper voltage limit will be input into the reference voltage upper bound input end of analog/digital converter 403, and this lower voltage limit will be input into the reference voltage lower bound input end of analog/digital converter 403, with the upper bound and the lower bound of the reference voltage that is used for being used as analog/digital converter 403.Function by analog-digital converter 403 itself, this output voltage that is transfused to can be converted to corresponding digital signal with the expression 329 first coordinate elements that correspond to the coordinate of Touch Screen 320 of starting to write a little, and via digital signal output end 461 outputs.After obtaining this first coordinate element, the switch that is coupled between first voltage output end 321 and the analog/digital converter 403 cuts out, to measure 329 programs of the second coordinate element that correspond to the coordinate of Touch Screen 320 of starting to write a little.
When carrying out subordinate phase of the present invention when obtaining starting to write a little 329 the second coordinate element that coordinate was comprised, close the 3rd switching transistor 309 and the 4th switching transistor 311, and open first switching transistor 305 and second switch transistor 307, therefore will produce an output voltage at tertiary voltage output terminal 325 this moment.The switch 471 that be coupled between the input end of analog signal 455 of first voltage output end 321 and analog/digital converter 403 this moment is to be closed condition, and the switch 473 that is coupled between the input end of analog signal 455 of tertiary voltage output terminal 325 and analog/digital converter 403 is to be opening, so this output voltage can be directly inputted into input end of analog signal 455.At this moment, organize minion and close the on off state that transistor 439 and this control signal of organizing the control end of octavo pass transistor 441 are controlled each switching transistor by being coupled in this, so that the 5th voltage output end 447 produce one near but greater than the upper voltage limit of this second output voltage, and make the 6th voltage output end 449 produce one near but less than the lower voltage limit of this second output voltage, wherein this group control signal is to be used for measuring 329 these the second group of digital signal of the second coordinate element that correspond to the coordinate of Touch Screen 320 of starting to write a little for what successive approximation register 335 in the phase one of the present invention exported.This upper voltage limit will be input into the reference voltage upper bound input end of analog/digital converter 403, and this lower voltage limit will be input into the reference voltage lower bound input end of analog/digital converter 403, with the upper bound and the lower bound of the reference voltage that is used for being used as analog/digital converter 403.Function by analog/digital converter 403 itself, this output voltage that is transfused to can be converted to corresponding digital signal with the expression 329 second coordinate elements that correspond to the coordinate of Touch Screen 320 of starting to write a little, and via digital signal output end 461 outputs.After obtaining this second coordinate element, the switch that is coupled between the input end of the 3rd output voltage terminal 325 and analog/digital converter 403 cuts out, to carry out the first coordinate element and the second coordinate element of start to write a little 329 the coordinate of subordinate phase of the present invention after continuing to measure once more.
The employed measurement of subordinate phase of the present invention the start to write first coordinate element of the coordinate that a little corresponds to Touch Screen and the principle of the second coordinate element, be for find out one group of referential digital signal of the switch combination representative of each switching transistor among Fig. 8 earlier by the phase one of the present invention, in subordinate phase of the present invention, to utilize the output voltage that switch combination was produced of this kind switching transistor, the i.e. voltage that produced of the 5th voltage output end 447 and the 6th voltage output end 449, offset the error that voltage difference produced of switching transistor in the single-ended mode itself in advance, it is identical with differential mode adding the present invention, the voltage that has used the sense of touch system to be produced is used as reference voltage, so the present invention can have the degree of accuracy as the differential mode.This is organized referential digital signal and will continue to be stored in this artificial circuit, so that resistance touch screen measuring system of the present invention can continue to measure a little the coordinate of starting to write of diverse location next.
The start to write mode of the coordinate position of corresponding Touch Screen a little of resistance touch screen measuring system measurement of the present invention is comparatively similar to the employed measuring method of the resistance touch screen measuring system of single-ended mode, significant difference place is that the reference voltage upper limit that analog/digital converter is imported and reference voltage lower limit change the reference voltage upper limit and the reference voltage lower limit that the digital signal that voltage produced of holding according to starting to write determines into by direct supply VDD originally and earth terminal GND, therefore analog/digital converter is after the reference voltage upper limit and reference voltage lower limit of the digital signal that voltage produced decision of end started to write in input, just first switching transistor and second switch ground crystal (or the 3rd switching transistor and the 4th switching transistor) can be closed, therefore the power that consumes can be reduced to the degree of the resistance touch screen measuring system that uses single-ended mode.
The above only is preferred embodiment of the present invention, and all equalizations of being done according to the present patent application claim change and modify, and all should belong to covering scope of the present invention.
Claims (5)
1. resistance touch screen measuring system comprises:
One first switch, its first end are to be coupled in one first power supply;
One second switch, one end are to be coupled in a second source;
One the 3rd switch, its first end are to be coupled in this first power supply;
One the 4th switch, the one end be coupled in this second source;
One first resistance is coupled between this first switch and this second switch in the mode of connecting;
One the 3rd resistance is coupled between the 3rd switch and the 4th switch in the mode of connecting;
One comparer, its first input end are second ends that is coupled in this first switch;
One the 9th switch is coupled between second end of the first input end of this comparer and this first switch;
The tenth switch is coupled between second end of the first input end of this comparer and the 3rd switch,
One successive approximation register, its input end are the output terminals that is coupled in this comparer; And
One artificial circuit, it comprises:
One the 5th resistance;
One the 5th switch, its first end are to be coupled in this first power supply, and second end is second input end that is coupled in the 5th resistance and this comparer;
One the 6th switch is coupled between the 5th resistance and this second source;
One group of minion is closed, and is coupled between the 5th resistance and this first power supply in the mode that is parallel to the 5th switch, and this control end of organizing each switch of minion pass is an output terminal that is coupled in one group of output terminal of this successive approximation register;
One group of octavo is closed, and is coupled between the 5th resistance and this second source in the mode that is parallel to the 6th switch, and this control end of organizing each switch of octavo pass is an output terminal that is coupled in this group output terminal of this successive approximation register,
Wherein, this artificial circuit comprises one group of phase inverter in addition, and each phase inverter is to be coupled between the output terminal of this group output terminal of this control end of organizing the switch that minion closes and this successive approximation register.
2. touch screen measuring system as claimed in claim 1, wherein, this first switch, the 5th switch, the 6th switch, this each switch and this each switch of organizing the minion pass of organizing the octavo pass are to be the P-type mos transistor.
3. touch screen measuring system as claimed in claim 1, wherein, this second switch is a N type metal oxide semiconductor transistor.
4. touch screen measuring system as claimed in claim 1, wherein, the 3rd switch is to be the P-type mos transistor.
5. touch screen measuring system as claimed in claim 1, wherein, the 4th switch is a N type metal oxide semiconductor transistor.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2005101184130A CN100410862C (en) | 2005-10-28 | 2005-10-28 | Resistance touch screen measuring system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2005101184130A CN100410862C (en) | 2005-10-28 | 2005-10-28 | Resistance touch screen measuring system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1955905A CN1955905A (en) | 2007-05-02 |
| CN100410862C true CN100410862C (en) | 2008-08-13 |
Family
ID=38063264
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNB2005101184130A Expired - Fee Related CN100410862C (en) | 2005-10-28 | 2005-10-28 | Resistance touch screen measuring system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN100410862C (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7868877B2 (en) * | 2007-10-18 | 2011-01-11 | Freescale Semiconductor, Inc. | Touch panel detection circuitry and method of operation |
| CN101424994B (en) * | 2007-10-30 | 2010-11-03 | 华硕电脑股份有限公司 | Touch control display apparatus and method for judging touch control manner |
| JP5220201B2 (en) * | 2008-11-20 | 2013-06-26 | サーク・コーポレーション | Method and system for measuring position on a surface capacitive touch panel using a flying capacitor |
| TWI402730B (en) * | 2009-09-30 | 2013-07-21 | 晶宏半導體股份有限公司 | Control module of touch module |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5717321A (en) * | 1995-01-17 | 1998-02-10 | Cirrus Logic, Inc. | Drive current calibration for an analog resistive touch screen |
| US5815141A (en) * | 1996-04-12 | 1998-09-29 | Elo Touch Systems, Inc. | Resistive touchscreen having multiple selectable regions for pressure discrimination |
| CN1367424A (en) * | 2001-01-22 | 2002-09-04 | 达方电子股份有限公司 | Detector of mouse touch control board and its method |
| CN1420474A (en) * | 2001-11-19 | 2003-05-28 | 宏达国际股份有限公司 | Method for testing touch point coordinate for resistance type touch controlled panel |
-
2005
- 2005-10-28 CN CNB2005101184130A patent/CN100410862C/en not_active Expired - Fee Related
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5717321A (en) * | 1995-01-17 | 1998-02-10 | Cirrus Logic, Inc. | Drive current calibration for an analog resistive touch screen |
| US5815141A (en) * | 1996-04-12 | 1998-09-29 | Elo Touch Systems, Inc. | Resistive touchscreen having multiple selectable regions for pressure discrimination |
| CN1367424A (en) * | 2001-01-22 | 2002-09-04 | 达方电子股份有限公司 | Detector of mouse touch control board and its method |
| CN1420474A (en) * | 2001-11-19 | 2003-05-28 | 宏达国际股份有限公司 | Method for testing touch point coordinate for resistance type touch controlled panel |
Also Published As
| Publication number | Publication date |
|---|---|
| CN1955905A (en) | 2007-05-02 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN104390715B (en) | Temperature conversion method and a low-power high-precision integrated temperature sensor | |
| CN101477152B (en) | Capacitance detection apparatus and method | |
| US7643014B2 (en) | Resistive touch screen measurement system | |
| CN104729724A (en) | Single-photon avalanche diode quenching circuit based on offset control differential amplification structure | |
| CN100410862C (en) | Resistance touch screen measuring system | |
| CN107465407A (en) | A kind of earth leakage protective type bootstrapping sampling switch circuit and equipment | |
| CN104571734A (en) | Self-mutual capacitance detection circuit and capacitive touch panel | |
| CN108322199B (en) | Dynamic comparison method | |
| CN107515050B (en) | A kind of infrared focal plane read-out circuit | |
| CN107764431B (en) | Chip core temperature detection circuit | |
| CN107247190B (en) | A kind of capacitive detection circuit using charge zoom technology | |
| CN109282856A (en) | It is a kind of while detecting temperature/voltage/current signal single-chip sensor | |
| CN104483033B (en) | A kind of CMOS temperature transmitter circuit of wide temperature range | |
| CN111366259B (en) | Reconfigurable all-digital temperature sensor and temperature measurement method | |
| CN201382977Y (en) | Capacitor measuring device | |
| CN103532559B (en) | Circulation timei digital quantizer | |
| CN208818364U (en) | Temperature measuring circuit | |
| CN105406875A (en) | Key detection circuit | |
| CN105119601A (en) | Multi-channel selection circuit suitable for high-speed and high-precision analog-to-digital converter | |
| CN105846812B (en) | A kind of electric current automatic switch-over circuit and its implementation | |
| CN108955930A (en) | temperature measuring circuit | |
| CN102109389A (en) | Temperature detection circuit | |
| CN113671258A (en) | Touch screen channel short-circuit resistance measuring circuit and method | |
| CN102541267B (en) | Matrix keyboard circuit, scanning method and device, processor and handheld terminal | |
| CN104135291A (en) | Successive approximation register type analog-digital converter implemented in pulse current charge form |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20080813 Termination date: 20171028 |
|
| CF01 | Termination of patent right due to non-payment of annual fee |