JPS5770404A - Capacitance detecting circuit - Google Patents

Capacitance detecting circuit

Info

Publication number
JPS5770404A
JPS5770404A JP14720180A JP14720180A JPS5770404A JP S5770404 A JPS5770404 A JP S5770404A JP 14720180 A JP14720180 A JP 14720180A JP 14720180 A JP14720180 A JP 14720180A JP S5770404 A JPS5770404 A JP S5770404A
Authority
JP
Japan
Prior art keywords
voltage
sensor
comparator
output
capacity
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.)
Granted
Application number
JP14720180A
Other languages
Japanese (ja)
Other versions
JPH0141240B2 (en
Inventor
Toshimine Ide
Takeshi Shimamoto
Yoshiaki Igarashi
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Panasonic Holdings Corp
Original Assignee
Matsushita Electric Industrial Co Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Matsushita Electric Industrial Co Ltd filed Critical Matsushita Electric Industrial Co Ltd
Priority to JP14720180A priority Critical patent/JPS5770404A/en
Priority to US06/312,846 priority patent/US4404481A/en
Publication of JPS5770404A publication Critical patent/JPS5770404A/en
Publication of JPH0141240B2 publication Critical patent/JPH0141240B2/ja
Granted legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
    • G01L9/00—Measuring steady of quasi-steady pressure of fluid or fluent solid material by electric or magnetic pressure-sensitive elements; Transmitting or indicating the displacement of mechanical pressure-sensitive elements, used to measure the steady or quasi-steady pressure of a fluid or fluent solid material, by electric or magnetic means
    • G01L9/0041—Transmitting or indicating the displacement of flexible diaphragms
    • G01L9/0072—Transmitting or indicating the displacement of flexible diaphragms using variations in capacitance
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01D—MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
    • G01D3/00—Indicating or recording apparatus with provision for the special purposes referred to in the subgroups
    • G01D3/02—Indicating or recording apparatus with provision for the special purposes referred to in the subgroups with provision for altering or correcting the law of variation
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01D—MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
    • G01D5/00—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable
    • G01D5/12—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means
    • G01D5/14—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means influencing the magnitude of a current or voltage
    • G01D5/24—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means influencing the magnitude of a current or voltage by varying capacitance
    • G01D5/241—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means influencing the magnitude of a current or voltage by varying capacitance by relative movement of capacitor electrodes
    • G01D5/2417—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means influencing the magnitude of a current or voltage by varying capacitance by relative movement of capacitor electrodes by varying separation
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
    • G01L9/00—Measuring steady of quasi-steady pressure of fluid or fluent solid material by electric or magnetic pressure-sensitive elements; Transmitting or indicating the displacement of mechanical pressure-sensitive elements, used to measure the steady or quasi-steady pressure of a fluid or fluent solid material, by electric or magnetic means
    • G01L9/12—Measuring steady of quasi-steady pressure of fluid or fluent solid material by electric or magnetic pressure-sensitive elements; Transmitting or indicating the displacement of mechanical pressure-sensitive elements, used to measure the steady or quasi-steady pressure of a fluid or fluent solid material, by electric or magnetic means by making use of variations in capacitance, i.e. electric circuits therefor
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03K—PULSE TECHNIQUE
    • H03K17/00—Electronic switching or gating, i.e. not by contact-making and –breaking
    • H03K17/94—Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the way in which the control signals are generated
    • H03K17/965—Switches controlled by moving an element forming part of the switch
    • H03K17/975—Switches controlled by moving an element forming part of the switch using a capacitive movable element

Abstract

PURPOSE:To eliminate the need for correction of linearity and to make circuit constitution simple by generating the DC voltage proportional to the change in the capacity of a capacity changing type sensor. CONSTITUTION:A capacity changing type sensor and a reference sensor 7 are charged respectively by charging circuits 8, 9, and when the voltage 21 of a connection point (b) rises higher than reference voltage Vref1, the output of a comparator 13 inverts to a high level. Further when the voltage 20 of a connection point (a) rises higher than the voltage Vref1 upon lapse of time, the output 24 f a comparator 12 inverts, and a monostable multivibrator 15 is triggered to operate charging circuits 10, 11, by which the electric charge acumulated in the sensor 6 and the capacitor 7 is discharged. When there are no more output pulses 23 of the vibrator 15, the circuits 10, 11 stop operation, ad again the charging is started. The pulse signal 22 of the average voltage changing in proportion to the physical quantity a applied to the sensor 6 is obtained from the comparator 13.
JP14720180A 1980-10-20 1980-10-20 Capacitance detecting circuit Granted JPS5770404A (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
JP14720180A JPS5770404A (en) 1980-10-20 1980-10-20 Capacitance detecting circuit
US06/312,846 US4404481A (en) 1980-10-20 1981-10-19 Capacitance to voltage conversion apparatus

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP14720180A JPS5770404A (en) 1980-10-20 1980-10-20 Capacitance detecting circuit

Publications (2)

Publication Number Publication Date
JPS5770404A true JPS5770404A (en) 1982-04-30
JPH0141240B2 JPH0141240B2 (en) 1989-09-04

Family

ID=15424837

Family Applications (1)

Application Number Title Priority Date Filing Date
JP14720180A Granted JPS5770404A (en) 1980-10-20 1980-10-20 Capacitance detecting circuit

Country Status (1)

Country Link
JP (1) JPS5770404A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5910014U (en) * 1982-07-12 1984-01-21 横河電機株式会社 capacitive converter
JPS59142418A (en) * 1983-02-02 1984-08-15 Matsushita Electric Ind Co Ltd Physical quantity detecting device
JP2009174978A (en) * 2008-01-24 2009-08-06 Fujikura Ltd Capacitive sensor

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5910014U (en) * 1982-07-12 1984-01-21 横河電機株式会社 capacitive converter
JPH0122085Y2 (en) * 1982-07-12 1989-06-29
JPS59142418A (en) * 1983-02-02 1984-08-15 Matsushita Electric Ind Co Ltd Physical quantity detecting device
JP2009174978A (en) * 2008-01-24 2009-08-06 Fujikura Ltd Capacitive sensor

Also Published As

Publication number Publication date
JPH0141240B2 (en) 1989-09-04

Similar Documents

Publication Publication Date Title
US4567465A (en) Method and apparatus for converting analog signal into digital signal
GB1375609A (en)
ES8106990A1 (en) Pulse generator for a horizontal deflection system
JPS5651674A (en) Level detecting circuit
GB1508151A (en) Signal rate to voltage converter
JPS5770404A (en) Capacitance detecting circuit
DE69027329T2 (en) ANALOG-DIGITAL VOLTAGE CONVERTER WITH FINE ADJUSTMENT
JPS57152218A (en) Frequency and voltage converting circuit
GB1513583A (en) Frequency modulator
ES8800538A1 (en) Analog-to-digital converter.
SU1190299A1 (en) Digital resistance meter
SU752364A1 (en) Multiplier-divider
SU828166A1 (en) Time interval measuring device
SU966892A1 (en) Voltage-to-frequency converter
JPS5552629A (en) Signal detection circuit
SU385289A1 (en) FREQUENCY-PULSE DIFFERENTIATING DEVICE
SU391723A1 (en) FREQUENCY CONVERTER TO DC VOLTAGE
FR2385089A1 (en) Average temp. measurement over time period - is achieved by integrating current from temp. probe thermistor
SU801244A1 (en) Analogue-digital converter
JPS57196620A (en) Integration type analog-to-digital converter
SU457178A1 (en) Voltage to Pulse Frequency Converter
JPS6459091A (en) Battery capacity detecting device
SU1415035A1 (en) Time interval-to-displacement converting device
JPS55112511A (en) Capacitive displacement gauge
JPS5776922A (en) Timer circuit