CN1167371A - CMOS capacitor type proximity switch - Google Patents
CMOS capacitor type proximity switch Download PDFInfo
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- CN1167371A CN1167371A CN 96112991 CN96112991A CN1167371A CN 1167371 A CN1167371 A CN 1167371A CN 96112991 CN96112991 CN 96112991 CN 96112991 A CN96112991 A CN 96112991A CN 1167371 A CN1167371 A CN 1167371A
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Abstract
The present invention provides a capacitor type proximity switch using original input capacitance of CMOS element input end as comparative reference, and called electronic switch, and is switching value and analogue type proximity switch. In particular it is applicable to range measurement, thickness measurement, selection of materials with various sizes and tapes, control of conveying belt, fluctuation measurement, aperture measurement, control of location, detection of nonuniformity, continuous detection of liquid level and counting of working pieces on production-line. Besides, said invented proximity switch can be used for changing gear type counter (for example watt-hour meter, water meter, flow meter and speedometer) into micropower consumption LCD counting meter.
Description
The present invention relates to a kind of capacitive proximity switch, claim electronic switch again, and be switching value and analog quantity type near switch, be specially adapted to find range, thickness measuring, the material of selecting different size and type, control conveyer belt, measure the counting of workpiece on fluctuation, the continuous detecting of measuring aperture, positioning control, detection unevenness, liquid level and the streamline etc.
Existing capacitor type proximity switch is a higher-order of oscillation type, draws detecting electrode (claiming to detect face again) at home and abroad by oscillating circuit, with the capacitance variations that constitutes near object (metal or nonmetal), makes vibration starting of oscillation or failure of oscillation, provides the switching signal that detects and control.This detection distance near switch, examined electrode size restricts, and switching frequency, lagging characteristics, repeatable accuracy and temperature drift etc. are all not satisfactory.
The objective of the invention is at above-mentioned shortcoming, a kind of handle is proposed near thing (metal or nonmetal) and the capacitance of drawing the detecting electrode formation outward, be superimposed upon on the intrinsic input capacitance of COMS element input (abbreviation input capacitance), form steady-state circuit by outer meeting resistance, or charge and discharge circuit with electronic switch and gate circuit and outer meeting resistance composition cycle, be converted to the electronic pulse width amount, through comparison and broadening, or compare with pulse duration and no steady oscillation cycle, detection as switching value, or be subdivided into the detection of analog quantity, detection and utilization scope have been enlarged, make it detect distance, switching frequency, lagging characteristics, repeatable accuracy and temperature drift index are compared with existing capacitor type proximity switch and all to be significantly increased and to improve.
Be described below according to COMS capacitor type proximity switch provided by the present invention, intrinsic input capacitance and outer meeting resistance with the COMS element input that can constitute monostable flipflop, the monostable circuit of forming two elements and the identical symmetry of parameter, or charge and discharge circuit with the electronic switch of COMS element and door input capacitance and outer meeting resistance composition cycle, one of them input has the outer detecting electrode (claim to detect face again---down with omitting) that draws, when outside no external object (metal or nonmetal---omission together down) is approaching, drawing detecting electrode, two monostable circuits under the trigger impulse effect of same frequency or the cycle charge and discharge circuit under same FREQUENCY CONTROL, resistance adjustment with potentiometer, it is identical to make two monostable circuits or cycle charge and discharge the output arteries and veins circuit of circuit, its residual quantity of comparing is output as zero, when outside external object is approaching, drawing detecting electrode, external object and the capacitance of drawing the detecting electrode formation outward, be superimposed upon on the intrinsic input capacitance of COMS element input (addition in parallel), Dui Ying this monostable trigger-action circuit or cycle charge and discharge the increasing of circuit output pulse width thus, charging and discharging circuit with monostable circuit of drawing detecting electrode outside the nothing or cycle compares, the pulse of two difference in pulse width is arranged, trigger the monostable circuit of output stage one pulse stretching again with this pulse, export the pulse that width is big, promote diode displaying, as the signal of promising near switch output, or with in addition frequency multiplication segmentation of the pulse of above-mentioned two difference in pulse width, or also amplified the output that provides digital quantity or analog quantity by pulse duration and voltage transitions.
Advantage of the present invention:
1, need not to form the height oscillating circuit that shakes with inductance element, circuit is simple, and is with low cost, and power consumption is low, but whole circuit COMSization is convenient to assembled package or special use is integrated, realizes that circuit of the present invention can variedization.
2, external object with draw the capacitance variations that detecting electrode causes outward, charge and discharge the detection that circuit is converted to pulse duration by monostable circuit or cycle, it is highly sensitive, circuit is stable, it is little to drift about, the same distance of promising, it is outer to draw the face of detecting electrode less than the existing face that draws detecting electrode near switch outward.
3, above-mentioned changes in capacitance amount, charging and discharging the pulse width variation amount that circuit is converted to RC by monostable circuit or cycle is a clear and definite linear relationship, help range finding, thickness measuring, select detections such as different size and types of material, and the output of analog quantity etc.
4, do not have inductance element in the circuit, need not to use NULL near the shell of switch, available magnetic conductive metal---iron etc., simplified manufacturing technique reduces cost, and has overcome existing higher-order of oscillation type near the difficult shortcoming that can be integrated of switch.
5, utilize switch of the present invention that the count table of gear type (as kilowatt-hour meter, water meter, flowmeter and mileage etc.) is changed into little power consumption liquid crystal digital and show that count table is very economical and easy.
6, circuit of the present invention is applicable to the detection of differential capacitor amount and is used in the detection of the capacitance change of capacitance sensor, as the inventor's patent (ZL86106551.4)---and the detection of grid shape capacitive position transducer capacitance change.
7, each circuit of the present invention is comprehensive, can be made into the wide chip integrated circuit of versatility, and switching signal is arranged, analog and digital signal is also arranged, resolution height, reliability height, change outward element, adapt to different function requirements, chip divides class by precision, on request distribution chip, satisfy the capacitor type proximity switch of switching value and analog quantity, the detection of the testing circuit of making capacitance type transducers and other specific (special) requirements is joined in the detection of various capacitances, has fully improved the percentage of chip yield.
The present invention is by relevant necessary be described with reference to the accompanying drawings for example following (graphic symbol with GB4728 " electric diagram schematic symbol " drafting):
Fig. 1 structural representation of the present invention;
Fig. 2 the present invention is by intrinsic input capacitance of COMS element input that can constitute monostable flipflop and monostable circuit that outer meeting resistance is formed;
Relevant waveform when Fig. 3 Fig. 2 of the present invention draws detecting electrode (1) outside external object is approaching;
Fig. 4 the present invention is by the intrinsic input capacitance of COMS gate element input, and outer meeting resistance and electronic switch are formed the cycle charge-discharge circuit;
The comparison circuit that Fig. 5 the present invention forms monostable and no stable state by the intrinsic input capacitance and the outer meeting resistance of COMS element input;
The fundamental mode circuit of Fig. 6 high accuracy number amount of the present invention or analog quantity.
Fig. 1 is a structural representation of the present invention, gives an example with cylindrical housing.1. draw detecting electrode outward; 2. shell is with plastics or metal (comprising magnetic conductive metal iron etc.); 3. hold-down nut; 4. circuit element; 5. adjustable potentiometer; 6. display element LED; Power supply and output outer lead.
Fig. 2 monostable circuit that to be the present invention be made up of the intrinsic input capacitance of the COMS element input that can constitute monostable flipflop and outer meeting resistance R1 and R2, the master makes oscillator by resistance R 3 among the figure, R4, the square-wave oscillator that capacitor C 1 and dual input NAND gate (CC4011) are formed, its square wave output produces trigger impulse through resistance R 5 and capacitor C 2, trigger monostable circuit A1 and B1 simultaneously, form two identical monostable circuits of parameter of A1 and B1 by two monostable flipflops (CC4538), wherein A1 monostable circuit RX/CX termination one draw detecting electrode 1 outward, two monostable circuits of A1 and B1 and pulse output width, depend on two equal resistors R1 and R2, the input capacitance size of potentiometer W1 and RX/CX end, for the A1 monostable circuit, to depend on that also external object is near the state that draws detecting electrode 1 outward, draw detecting electrode 1 no external object outside when near, regulator potentiometer W1, two monostable output pulse widths of A1 and B1 are equated, its difference of comparing heavily is output as zero, when external object near outside when drawing detecting electrode 1 with outside draw the capacitance that detecting electrode constitutes, be superimposed upon on the input capacitance of RX/CX end of A1 monostable circuit (addition in parallel), the pulse duration of output Q1 becomes big, and with B1 monostable circuit output Q2, (CC4011) compares through the dual input NAND gate, draw the negative pulse of two difference in pulse width, again by the monostable circuit of output stage with its paraphase and broadening, the monostable circuit of output stage is by CC7555 (or NE555), resistance R 6, capacitor C 3, C4 forms, output pulse width depends on R6 and C3 parameter, can directly promote light-emitting diode D1 and control relay with NE555, R7 is a current-limiting resistance, or controls the high-voltage thyristor element with optocoupler components.
Fig. 3 be corresponding diagram 2 outer draw detecting electrode 1 have external object near the time, the triggering of CC4538 and CC7555 and output waveform figure.
Form the foregoing circuit master and make oscillator, monostable circuit is compared circuit with pulse duration element and approach are a lot, as CC4001, CC4011, CC4013, CC4043, CC4069, CC4071, CC4081, CC4093, CC4098, CC40106, CC4528, CC4538 etc.Fig. 2 is listed, only is illustrational a kind of, and following each circuit also as showing, is no longer reaffirmed.Exemplifying of Fig. 2 made full use of each interior functional block of integration member, and the circuit volume is little, is convenient to assembled package.
The intrinsic input capacitance of COMS element input is about 5PF, input resistance has two monostable flipflops (this routine CC4538 is two accurate monostable flipflops) greater than the existing integration member of 108 Ω, two electric parameters and manufacturing process thereof are identical, select the input capacitance of this two RX/CX end benchmark of making comparisons, its temperature effect is little, and reference capacitance is little, highly sensitive, this class component is wide in variety, and versatility is big, and is cheap, this circuit does not have amplification system, its good stability, the reliability height, operating frequency depends on master oscillator frequenc, no inductance element, no lagging characteristics, its switching frequency, characteristic such as repeatable accuracy and temperature drift is all good than existing capacitor type proximity switch.
Fig. 4 is that the present invention is by the intrinsic input capacitance of COMS element door input, outer meeting resistance and electronic switch composition cycle charge and discharge circuit, wherein A2 and the B2 cycle that the electronic switch KA1 of two COMS elements is identical with parameter with two elements of R11 composition with outer meeting resistance R10 with the input capacitance of KB1 (CC4066) and gate circuit DA and DB (CC4069) charges and discharge circuit, gate circuit DA input has one to draw detecting electrode 1 outward in the A2 circuit, resistance R 8, R9, capacitor C 5 and gate circuit (CC4069) are formed the main oscillator that makes, shaping and paraphase through gate circuit (CC4069), before connect electronic switch KC1 switch during the half period, disconnect electronic switch KA1 and KB1, power vd D is through electronic switch KC1, adjustable point in the middle of the potentiometer W2, respectively to two equal resistors R10 and R11, to DA and the intrinsic input capacitance charging of DB door (4069) input, disconnect electronic switch KC1 switch during later half cycle, connect electronic switch KA1 and KB1, DA and DB door input are by electronic switch KA1 and the direct ground connection discharge of KB1.Draw outside detecting electrode 1 no external object near the time, regulator potentiometer W2, the output pulse width that makes A2 and B2 cycle charge and discharge circuit equates.When outside draw detecting electrode 1 have external object near the time, with the capacitance of drawing detecting electrode 1 formation outward, the cycle of being superimposed upon charges and discharge on the input capacitance of DA gate circuit input of circuit A2 (addition in parallel), the output pulse width that charges and discharge circuit A2 becomes big Dui Ying cycle thus, compare with the output pulse width that the outer cycle of drawing detecting electrode of nothing charges and discharge circuit B2, the pulse of two difference in pulse width is arranged, Fig. 4 compares two pulse durations with dual input NOR gate (CC4001), in addition, form the output stage monostable circuit with two dual input NOR gate (CC4001) and resistance R 12 with capacitor C 6 in addition, use triode BG1, diode D2 and resistance R 13, R14 forms power amplification circuit, promotes light-emitting diode D3, or controls the high-voltage thyristor element with optocoupler components.
Use said elements, for making full use of existing integration member functional block, be convenient to assembled package equally, it is a kind of that this just gives an example, and it is a lot of to form this circuit element kind.
The RX/CX of A1 and two monostable circuits of B1 end in Fig. 2, increase by two and charge and discharge the electronic switch (KA1 and KB2) of identical connection and control mode in the circuit (Fig. 4) with the cycle, in the main preceding half period that makes oscillator is that monostable circuit (A1 and B1) is when locating the monostable phase of what (monostable phase output width is less than main 1/2 cycle of oscillation that makes oscillator), electronic switch disconnects, it is the non-monostable phase of monostable circuit place what that the master makes the later half cycle of oscillator, electronic switch is connected, the RX/CX end is by electronic switch ground connection, RX/CX end ground connection before promptly entering the monostable phase, the charging current initial value of guaranteeing input capacitance is zero, improves its sensitivity and reliability.
Fig. 5 is made of the comparison circuit of monostable and no stable state intrinsic input capacitance of COMS element input and outer meeting resistance, compare with the no steady oscillation cycle with monostable pulse output width, the A3 circuit is identical with the A1 circuit, by resistance R 15, R17, capacitor C 8, potentiometer W3 and CC4528 form monostable circuit, the B3 circuit is by resistance R 16, R18, capacitor C 9 and CC4528 form astable oscillator, after energized, Q2 is a high potential, by resistance R 18 after the capacitor C 9 of TR+ end charges to activation threshold value, enter the monostable phase, Q2 is a high potential, Q2 is an electronegative potential, the monostable phase finishes, Q2 becomes high potential again, repeat said process and form no steady oscillation, monostable circuit A3 is triggered by Q2 end trailing edge, draw outside detecting electrode 1 no external object near the time, selected resistance R 15 and regulator potentiometer W3 make A3 monostable output pulse (Q1) width, less than and approach astable circuit B3 cycle of oscillation (T), Q1 end is the output of monostable pulse duration, when outside draw detecting electrode 1 have external object near the time, the A3 monostable is exported the cycle of oscillation (T) of pulse (Q1) width greater than astable circuit B3, so monostable circuit A3 is not before resetting, trigger once more, this just makes Q1 remain high potential output, is different from no external object near the state that draws detecting electrode outward.The demonstration of output stage and control can be similar to Fig. 2 or Fig. 4 (as CC7555 or NE555).The trigger impulse of monostable circuit A3 is obtained through resistance R 17 and capacitor C 8 differential by the Q2 of astable circuit B3 output.
Foregoing circuit is a kind of, and the also available square wave oscillation cycle is benchmark as a comparison, forms the square wave oscillation cycle with crystal oscillator, or positive half cycle benchmark as a comparison, and this is just more reliable and stable.
Fig. 6 is the fundamental mode circuit of high-precision analog amount output, the A1 monostable circuit identical among A4 and B4 and Fig. 2 among the figure with B1, and at the RX/CX of two monostable circuit A4 and B4 end, add two ground connection electronic switch KA2 and KB2s in parallel with intrinsic input capacitance, G1 is that the main oscillator that makes is except that control A4 and the triggering of B4 monostable trigger-action circuit, also control electronic switch KA2, KB2 and KC2 switch on and off, the C end of KA2 and KB2 links to each other with monostable circuit RX/CX end, d holds ground connection, control end e is subjected to the master to make oscillator G1 control, in the main preceding half period that makes oscillator G1, when monostable circuit A4 and monostable phase of B4 place what (the little what master of monostable output width makes 1/2 cycle of oscillation of oscillator), electronic switch (KA2 and KB2) disconnects, the main later half cycle (being monostable circuit A4 and non-monostable phase of B4 place what) that makes oscillator G1, electronic switch (KA2 and KB2) is subjected to the master to make oscillator G1 that control is switched on, the RX/CX end is opened (KA2 and KB2) ground connection by electronics, promptly enter monostable before the phase RX/CX end ground connection guarantee that the charging current initial value of input capacitance is zero, improve its sensitivity and reliability, the charge power supply of RX/CX is supplied with by the oscillator G2 of EDM Generator of Adjustable Duty Ratio, and controlled by electronic switch KC2, and connect synchronously when being triggered with the monostable circuit of A4 and B4, through electronic switch KC2 and diode D4 middle adjustable point to potentiometer W4, carry out the power supply of intermittence to two monostable circuit A4 and B4 respectively, this not only broadening the monostable output pulse width, and the duty ratio of change oscillator G2, can the monostable output pulse width of corresponding change, pulse duration residual quantity after two monostable is compared increases, improved sensitivity, be convenient to frequency multiplication segmentation or FV convertor and carry out the output of numeral or analog quantity.
The outer detecting electrode that draws of above-mentioned each circuit (except that Fig. 5) is removed, at the RX/CX of two monostable circuits end, or form the gate circuit input of cycle charge-discharge circuit by electronic switch and gate circuit, separately and connect the utmost point that pair of differential changes capacitance sensor, another utmost point ground connection, can be used as the detection of differential change capacitance sensor capacitance change, or the detection of other differential change capacitances.
Applicating example of the present invention:
Used element is CC4538 in Fig. 2, CC4011 and NE555, and wherein potentiometer W1 is 51K, R1=R2=200K, R3=470K, R4=47K, R5=20K, R6=1M, R7=100 Ω, C1=0.1 μ C2=510P, C3=0.01 μ, C4=0.1 μ
Claims (8)
1, the COMS capacitor type proximity switch has the outer detecting electrode (1 that draws, claim to detect face again---down with omitting), shell (2), hold-down nut (3), circuit element (4), adjustable potentiometer (5), display element (6) and power supply and output outer lead (7) are formed, it is characterized in that the intrinsic input capacitance of circuit by the COMS element input that can constitute monostable flipflop---be called for short input capacitance, monostable circuit (A1 and B1) with two identical symmetries of component parameters of outer meeting resistance (R1 and R2) composition, by main oscillator (the gate circuit CC4011 that makes, resistance R 3, R4 and capacitor C 1 formed square-wave oscillator) trigger two monostable circuits (A1 and B1) simultaneously or with the electronic switch (KA1 and KB1) of two COMS elements through capacitor C 2 and resistance R 5, the input capacitance of gate circuit (DA and BD) and outer meeting resistance (R10 and R11) two identical cycles of component parameters of composition charge and discharge circuit (A2 and B2), by main oscillator (the gate circuit CC4069 that makes, resistance R 8, R9 and capacitor C 5 are formed square-wave oscillator) preceding half period control electronic switch KC1 connection, KA1 and KB1 disconnect, the VDD power supply is through electronic switch KC1, adjustable point in the middle of the potentiometer W2, charge to the input capacitance of two equal resistors (R10 and R11) and gate circuit (DA and DB) respectively, later half periodic Control electronic switch KC1 disconnects, disconnect the charge power supply of gate circuit (DA and DB), electronic switch KA1 KB1 connects simultaneously, the input capacitance of gate circuit (DA and DB) is discharged over the ground by electronic switch (KA1 and KB1), draw the RX/CX input that detecting electrode (1) is connected on monostable circuit A1 outward, or the cycle of being connected on charges and discharge the input of the DA gate circuit of circuit A2, when outside no external object (metal and nonmetal---omission together down) is approaching, drawing detecting electrode (1), regulate the common potential device W1 of two monostable circuits (A1 and B1), or regulate the common potential device W2 that two cycles charge and discharge circuit (A2 and B2), make two monostable circuits (A1 and B1), or the output pulse width that two cycles charge and discharge circuit (A2 and B2) is identical, its residual quantity of comparing is output as zero, when outside external object is approaching, drawing detecting electrode (1), with the capacitance of drawing detecting electrode (1) formation outward, be superimposed upon the RX/CX end of monostable circuit A1.Or the cycle charges and discharge on the input capacitance of input of DA gate circuit of circuit A2 (addition in parallel), the output pulse width that charges and discharge circuit A2 becomes big Dui Ying monostable circuit A1 or cycle thus, compare with the output pulse width that monostable circuit B1 that draws detecting electrode (1) outside the nothing or cycle charge and discharge circuit B2, the pulse of two difference in pulse width is arranged, trigger the monostable circuit of output stage pulse stretching again (by resistance R 6 with this pulse, capacitor C 3, C4 and timer circuit 7555 are formed, or by resistance R 12, capacitor C 6 and gate circuit 4001 are formed), export the pulse that width is big, promoting the output demonstration (is made up of light-emitting diode D1 and current-limiting resistance R7, or by diode D2, resistance R 13, R14, capacitor C 7, triode BG1 and light-emitting diode D3 form), promise signal as output near switch, or with in addition frequency multiplication segmentation of the pulse of above-mentioned two difference in pulse width, or amplified the output that provides numeral or analog quantity by pulse duration and voltage transitions.
2, press the COMS capacitor type proximity switch of claim 1 defined, it is characterized in that two monostable circuits (A1 and B1) or two cycles charge and discharge circuit (A2 and B2) output pulse width relatively, use the two-input gate circuit, existing with, with non-, or, or non-and XNOR etc., relatively an one direct impulse (Q1) and another negative-going pulse (Q2) or two direct impulses (Q1 and Q2) all can.
3, COMS capacitor type proximity switch by claim 1 defined, the RX/CX end that it is characterized in that two monostable circuits (A1 and B1), increase by two and charge and discharge the electronic switch of identical connection of circuit and control mode with the cycle, when the master makes the preceding half period of oscillator be the monostable phase of monostable circuit place what (monostable output width is less than main 1/2 cycle of oscillation that makes oscillator), electronic switch disconnects, it is the non-monostable phase of monostable circuit place what that the master makes the later half cycle of oscillator, electronic switch is connected, the RX/CX end is by electronic switch ground connection, RX/CX end ground connection before promptly entering the monostable phase, the charging current initial value of guaranteeing input capacitance is zero, improves its sensitivity and reliability.
4, COMS capacitor type proximity switch by the claim defined, it is characterized in that two monostable circuits (A1 and B1) output pulse width relatively, with monostable circuit A3 (by resistance R 15, R17, capacitor C 8, potentiometer W3 and monostable trigger CC4528/2 form), with astable circuit B3 (by resistance R 16, R18, capacitor C 9 and monostable are sent out device CC4528/2 and are formed) output pulse width relatively, draw the RX/CX end that detecting electrode (1) is connected on monostable circuit A3 outward, draw outside the no external object of detecting electrode (1) near the time, regulator potentiometer W3 makes monostable circuit A3 output pulse (Q1) width, the cycle of oscillation (T) of little what and approaching no stable state, when outside draw detecting electrode (1) have external object near the time, the big what of monostable output pulse (Q1) width does not have the cycle of oscillation (T) of stable state, so before monostable circuit A3 does not reset, trigger once more, make the output (Q1) of monostable circuit A3 keep high potential, the difference what does not have external object near the state that draws detecting electrode (1) outward.The trigger impulse of monostable circuit A3 is obtained through resistance R 17 and capacitor C 8 differential by the Q2 of astable circuit B3 output.
5, by the COMS capacitor type proximity switch of claim 4 defined, it is characterized in that not having the steady oscillation cycle (T), form square wave oscillation cycle or the positive half cycle benchmark of making comparisons with crystal oscillator, more reliable and stable.
6, COMS capacitor type proximity switch by claim 1 regulation, the RX/CX end that it is characterized in that two monostable circuits (A4 and B4), add two with intrinsic input capacitance earthed switch in parallel (KA2 and KB2), in the main preceding half period that makes oscillator G1, when monostable circuit (A4 and B4) is located the monostable phase of what (the little what master of monostable output width makes 1/2 cycle of oscillation of oscillator), electronic switch (KA2 and KB2) disconnects, the main later half cycle (being monostable circuit A4 and non-monostable phase of B4 place what) that makes oscillator G1, electronic switch (KA2 and KB2) is subjected to the master to make oscillator G1 that control is switched on, the RX/CX end is by electronic switch (KA2 and KB2) ground connection, RX/CX end ground connection before promptly entering the monostable phase, the charging current initial value of guaranteeing input capacitance is zero, improve its sensitivity and reliability, the master makes oscillator G1 also control electronic switch KC1, in two monostable circuits (A4 and B4) when being triggered, connect electronic switch KC2 synchronously, by the square wave of the EDM Generator of Adjustable Duty Ratio device G2 that shakes, through electronic switch KC2, diode D4, the middle adjustable point of potentiometer W4, carry out the power supply of intermittence to two monostable circuits (A4 and B4) respectively, broadening monostable output pulse width, and change the duty ratio of square-wave oscillator, changed monostable output pulse width accordingly, increase the residual quantity of two monostable output pulse widths, improve sensitivity, be convenient to frequency multiplication segmentation or FV convertor and carry out the output of numeral or analog quantity.
7, by claim 1, the COMS capacitor type proximity switch of 3 and 6 regulations, it is characterized in that the outer detecting electrode (1) that draws that two monostable circuits (A1 and B1 or A4 and B4) or electronic switch and gate circuit and outer meeting resistance composition cycle charge and discharge in the circuit (A2 and B2) is removed, RX/CX at two monostable circuits (A1 and B1 or A4 and B4), or form the input that the cycle discharges and recharges two gate circuits (DA and DB) of (A2 and B2) by electronic switch and gate circuit and outer meeting resistance, separately and connect the utmost point that pair of differential changes electric capacity, another polar region, can be used as the detection of the electric capacity amount of differential change transducer, or the detection of other differential change electric capacity.
8, by claim, 1,2,3,4, the COMS capacitive proximity switch of 5 and 6 defineds, it is characterized in that foregoing circuit is comprehensively made the wide chip integrated circuit of versatility, switching signal is arranged, analog and digital signal is also arranged, the resolution height, the reliability height changes outward element, adapts to different function requirements, chip is by precision stepping parity, distribution chip on request satisfies the capacitor type proximity switch of switching value and analog quantity, the detection of various capacitances, the detection of joining the testing circuit of making capacitance type transducers and other specific (special) requirements has fully improved the percentage of chip yield.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN96112991A CN1100387C (en) | 1995-03-12 | 1996-02-06 | CMOS capacitor type proximity switch |
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN95205578 | 1995-03-12 | ||
| CN95205578.3 | 1995-03-12 | ||
| CN96112991A CN1100387C (en) | 1995-03-12 | 1996-02-06 | CMOS capacitor type proximity switch |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1167371A true CN1167371A (en) | 1997-12-10 |
| CN1100387C CN1100387C (en) | 2003-01-29 |
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ID=25743838
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN96112991A Expired - Fee Related CN1100387C (en) | 1995-03-12 | 1996-02-06 | CMOS capacitor type proximity switch |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN1100387C (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102439539A (en) * | 2009-05-22 | 2012-05-02 | 飞思卡尔半导体公司 | Device with proximity detection capability |
| CN103868442A (en) * | 2012-12-12 | 2014-06-18 | 王祖斌 | Differential capacitance displacement conversion and subdivision method and capacitive linear displacement measuring system |
| CN104268967A (en) * | 2014-09-29 | 2015-01-07 | 深圳市爱普特微电子有限公司 | Safety entrance guard method and device based on capacitance-type sensor |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0469634A1 (en) * | 1986-08-27 | 1992-02-05 | Ohmatoi Naoyuki | Pulse phase adjusting circuit for use with an electrostatic capacitor type sensor |
| CN87211201U (en) * | 1987-09-17 | 1988-06-08 | 夏士华 | Proximity switch adopting mos appliance |
| CN2051804U (en) * | 1988-09-30 | 1990-01-24 | 刘利民 | Proximity switch adopting cmos integrated circuit |
| CN2153909Y (en) * | 1993-03-10 | 1994-01-19 | 中外合资大连国耀电子企业有限公司 | Cmos time-delay touch switch |
-
1996
- 1996-02-06 CN CN96112991A patent/CN1100387C/en not_active Expired - Fee Related
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102439539A (en) * | 2009-05-22 | 2012-05-02 | 飞思卡尔半导体公司 | Device with proximity detection capability |
| CN103868442A (en) * | 2012-12-12 | 2014-06-18 | 王祖斌 | Differential capacitance displacement conversion and subdivision method and capacitive linear displacement measuring system |
| WO2014089892A1 (en) * | 2012-12-12 | 2014-06-19 | Wang Zubin | Differential capacitance displacement conversion and subdivision method and capacitive linear displacement measuring system |
| CN103868442B (en) * | 2012-12-12 | 2019-03-29 | 王祖斌 | The conversion of differential capacitance displacement and divided method and capacitive linear displacement measuring system |
| CN104268967A (en) * | 2014-09-29 | 2015-01-07 | 深圳市爱普特微电子有限公司 | Safety entrance guard method and device based on capacitance-type sensor |
Also Published As
| Publication number | Publication date |
|---|---|
| CN1100387C (en) | 2003-01-29 |
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