CN113411095B - Induction coil signal receiving circuit based on numerical control resonant frequency - Google Patents
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Abstract
The invention belongs to the field of industrial measurement and control, relates to a circuit, in particular to an induction coil signal receiving circuit based on numerical control resonance frequency, and is suitable for various application occasions for receiving electromagnetic wave signals based on induction coils. The invention comprises a connecting piece CN1, an induction coil CS1, a high-resistance operational amplifier IC1, a resonance operational amplifier IC2, an output operational amplifier IC3, a digital potentiometer IC4, coil internal resistance R0, a coil inductance L0, a resonance resistor R1, a negative terminal resistor R2, a resonance capacitor C1, a positive power supply capacitor C2, a negative power supply capacitor C3 and the like. The circuit of the invention utilizes an equivalent numerical control resonance capacitor circuit which takes a digital potentiometer with resistance value set based on serial communication as a core to tune, detect and receive electromagnetic wave signals in a wide frequency band so as to greatly improve the sensitivity of the electromagnetic wave signals in the detected frequency band. The invention has the advantages of simple circuit, high reliability, low cost, good safety and easy production.
Description
Technical Field
The invention belongs to the field of industrial measurement and control, relates to a circuit, in particular to an induction coil signal receiving circuit based on numerical control resonance frequency, and is suitable for various application occasions for receiving electromagnetic wave signals based on induction coils.
Background
The detection technology based on electromagnetic induction coil receiving electromagnetic wave signal is increasingly widely used, and is spread to various industries such as civil use, military use and the like. At present, the detection technology is mainly used for detecting single-frequency point electromagnetic wave signals, a plurality of induction coils are needed for detecting multi-frequency point electromagnetic wave signals, the cost is high, and the miniaturization and the portability of the whole detection device are not easy. Therefore, the design of the flexible resonance setting of the electromagnetic wave signals of the received frequency points by using the digital potentiometer and the communication technology can realize the high-sensitivity reception of the electromagnetic wave signals of a wide frequency band, and has wide application prospect.
Disclosure of Invention
The invention aims to provide a scheme of an induction coil signal receiving circuit based on numerical control resonance frequency aiming at the defects in the prior art. The invention has the advantages of simple circuit, high reliability, low cost, good safety and easy production.
An induction coil signal receiving circuit based on numerical control resonant frequency comprises a connecting piece CN1, an induction coil CS1, a high-resistance operational amplifier IC1, a resonant operational amplifier IC2, an output operational amplifier IC3, a digital potentiometer IC4, coil internal resistance R0, a coil inductor L0, a resonant resistor R1 and a negative terminal electric circuitA resistor R2, a resonant capacitor C1, a positive power supply capacitor C2 and a negative power supply capacitor C3, wherein the induction coil CS1 is internally provided with a coil internal resistance R0, a coil inductance L0 and a voltage induction signal source usThe three are connected IN series, one end of an induction coil CS1 is grounded, the other end of the induction coil CS1 is connected with one end of a resonance capacitor C1 and the positive input end IN + end of a high-resistance operational amplifier IC1, the output end OUT end of the high-resistance operational amplifier IC1 is connected with the negative input end IN-end of the high-resistance operational amplifier IC1, one end of a resonance resistor R1 and one end of a negative end resistor R2, the positive power end + V end of the high-resistance operational amplifier IC1 is connected with the positive power end + VCC end of the circuit, the negative power end-V end of a high-resistance operational amplifier IC1 is connected with the negative power end-VSS end of the circuit, the other end of a resonance resistor R1 is connected with the negative input end IN-end of a resonance operational amplifier IC2, the positive input end RH2 end and central end RW2 end of the 2 nd potentiometer IC4, the output end OUT end of the resonance operational amplifier IC2 is connected with the RL2 end of the 2 nd potentiometer IC4, the other end of the resonance capacitor C1, the resonance operational amplifier IC2 is grounded, the positive power supply terminal + V terminal of the resonant operational amplifier IC2 is connected to the positive power supply terminal + VCC terminal of the circuit, the negative power supply terminal-V terminal of the resonant operational amplifier IC2 is connected to the negative power supply terminal-VSS terminal of the circuit, the other end of the negative terminal resistor R2 is connected to the negative input terminal IN-terminal of the output operational amplifier IC3, the lower terminal RL1 terminal of the 1 st potentiometer of the digital potentiometer IC4, the output terminal OUT terminal of the output operational amplifier IC3 is connected to the upper terminal RH1 terminal of the 1 st potentiometer of the digital potentiometer IC4, the center terminal RW1 terminal, and the output signal terminal Uout terminal of the connecting piece CN1, the positive input terminal IN + terminal of the output operational amplifier IC3 is grounded, the positive power supply terminal + V terminal of the output operational amplifier IC3 is connected to the positive power supply terminal + VCC terminal of the circuit, the negative power supply terminal-V terminal of the output operational amplifier IC3 is connected to the negative power supply terminal-VSS terminal of the circuit, the positive power supply terminal of the digital potentiometer IC4 is connected to the positive power supply terminal GND terminal + VCC terminal of the circuit, and the ground terminal VCC 4 is grounded, the single bit address end A0 end of the digital potentiometer IC4, the ten bit address end A1 end of the digital potentiometer IC4, the hundred bit address end A2 end of the digital potentiometer IC4 and the thousand bit address end A3 end of the digital potentiometer IC4 are all grounded, the serial clock end SCL end of the digital potentiometer IC4 is connected with the clock end SCL end of the connecting piece CN1, the serial data end SDA end of the digital potentiometer IC4 is connected with the data end SDA end of the connecting piece CN1, the positive power end VCC end of the connecting piece CN1 is connected with the positive power end + VCC end of the circuit and the positive power capacitor end + VCC end of the circuitOne end of the C2 is connected, the negative power supply end VSS of the connecting piece CN1 is connected with the negative power supply end + VSS of the circuit and one end of the negative power supply capacitor C3, and the ground end GND of the connecting piece CN1, the other end of the positive power supply capacitor C2 and the other end of the negative power supply capacitor C3 are grounded.
Preferably, the circuit parameters are matched as follows:
us、Usmaxis the open-loop voltage signal of the induction coil and the maximum amplitude (unit: V), uiFor the induction coil, a voltage signal (unit: V), i is outputiFor the induction coil to output a current signal (unit: A), uout、UoutmaxIs the circuit output signal and its maximum amplitude (unit: V), omega is the angular frequency (unit: rad/s) of the induction signal, omega belongs to [ omega ]min，ωmax]，R0Is the internal resistance (unit: omega) of the induction coil, L0The inductance (unit: H) of the induction coil is shown, RP1 and RP2 are respectively the rated resistance (unit: omega) of the corresponding potentiometer in the digital potentiometer IC4,
resonance frequency:
equivalent capacitance:
output signal at resonance:
in the formula, RV1 and RV1 are respectively the output resistance values of RP1 and RP2 in a digital potentiometer IC4, namely W1-V1 end resistor and W2-V2 end resistor,
taking:
the invention has the following beneficial effects:
the invention adopts a simple circuit scheme, utilizes an equivalent numerical control resonance capacitor circuit which takes a digital potentiometer based on serial communication to set resistance as a core, and carries out tuning detection and reception on electromagnetic wave signals in a wide frequency band so as to greatly improve the sensitivity of the electromagnetic wave signals in the detected frequency band. The invention has the advantages of simple circuit, high reliability, low cost, good safety, easy productization and wide application range.
Drawings
Fig. 1 is a circuit diagram of the present invention.
Detailed Description
The invention will be further explained with reference to the drawings.
As shown in FIG. 1, an induction coil signal receiving circuit based on numerical control resonant frequency.
An induction coil signal receiving circuit based on numerical control resonant frequency comprises a connecting piece CN1, an induction coil CS1, a high-resistance operational amplifier IC1, a resonant operational amplifier IC2, an output operational amplifier IC3, a digital potentiometer IC4, coil internal resistance R0, a coil inductor L0, a resonant resistor R1, a negative end resistor R2, a resonant capacitor C1, a positive power supply capacitor C2 and a negative power supply capacitor C3, wherein a coil internal resistance R0, a coil inductor L0 and a voltage induction signal source u are arranged inside the induction coil CS1sThe three are connected IN series, one end of an induction coil CS1 is grounded, the other end of the induction coil CS1 is connected with one end of a resonance capacitor C1 and the positive input end IN + end of a high-resistance operational amplifier IC1, the output end OUT end of the high-resistance operational amplifier IC1 is connected with the negative input end IN-end of the high-resistance operational amplifier IC1, one end of a resonance resistor R1 and one end of a negative end resistor R2, the positive power end + V end of the high-resistance operational amplifier IC1 is connected with the positive power end + VCC end of the circuit, the negative power end-V end of a high-resistance operational amplifier IC1 is connected with the negative power end-VSS end of the circuit, the other end of a resonance resistor R1 is connected with the negative input end IN-end of a resonance operational amplifier IC2, the positive input end RH2 end and central end RW2 end of the 2 nd potentiometer IC4, the output end OUT end of the resonance operational amplifier IC2 is connected with the RL2 end of the 2 nd potentiometer IC4, the other end of the resonance capacitor C1, the resonance operational amplifier IC2 is grounded, resonant operational amplifierThe positive power end + V end of the IC2 is connected with the positive power end + VCC end of the circuit, the negative power end-V end of the resonant operational amplifier IC2 is connected with the negative power end-VSS end of the circuit, the other end of the negative end resistor R2 is connected with the negative input end IN-end of the output operational amplifier IC3 and the lower end RL1 end of the No. 1 potentiometer of the digital potentiometer IC4, the output end OUT end of the output operational amplifier IC3 is connected with the upper end RH1 end of the No. 1 potentiometer of the digital potentiometer IC4, the center end RW1 end and the output signal end Uout end of the connecting piece CN1, the positive power end IN + end of the output operational amplifier IC3 is grounded, the positive power end + V end of the output operational amplifier IC3 is connected with the positive power end + VCC end of the circuit, the negative power end V end of the output operational amplifier IC3 is connected with the negative power end GND-VSS end of the circuit, the positive power end of the digital potentiometer IC4 is connected with the positive power end VCC end of the circuit, the ground end of the digital potentiometer IC4 is grounded, the unit address end a0 end of the digital potentiometer IC4, the ten address end a1 end of the digital potentiometer IC4, the hundred address end a2 end of the digital potentiometer IC4 and the thousand address end A3 end of the digital potentiometer IC4 are all grounded, the serial clock end SCL end of the digital potentiometer IC4 is connected with the clock end SCL of the connecting piece CN1, the serial data end SDA end of the digital potentiometer IC4 is connected with the data end SDA end of the connecting piece CN1, the positive power end VCC end of the connecting piece CN1 is connected with the positive power end + VCC end of the circuit and one end of the positive power capacitor C2, the negative power end VSS end of the connecting piece CN1 is connected with the negative power end + VSS end of the circuit and one end of the negative power capacitor C3, and the ground end GND end of the connecting piece CN1 is connected with the other end of the positive power capacitor C2 and the other end of the negative power capacitor C3.
All devices used by the invention, including the high-resistance operational amplifier IC1, the resonant operational amplifier IC2, the output operational amplifier IC3, the digital potentiometer IC4 and the like, adopt the existing mature device products and can be obtained through the market. For example: TLC2264 was used for each operational amplifier, X9221 was used for the digital potentiometer, etc.
The main circuit parameters in the invention are matched as follows:
setting: u. ofs、UsmaxIs the open-loop voltage signal of the induction coil and the maximum amplitude (unit: V), uiFor the induction coil, a voltage signal (unit: V), i is outputiFor the induction coil to output a current signal (unit: A), uout、UoutmaxAs a circuitThe output signal and its maximum amplitude (unit: V), ω is the angular frequency (also resonance frequency) of the induction signal (unit: rad/s), ω ∈ [ ω [ ω ] [ [ ω ]min，ωmax]，R0Is the internal resistance (unit: omega) of the induction coil, L0The inductance (unit: H) of the induction coil is RP1 and RP2 which are respectively the rated resistance values (unit: omega) of two numerical control potentiometers in the digital potentiometer IC 4.
Resonance frequency:
equivalent capacitance:
output signal at resonance:
in the formula, RV1 and RV1 are respectively output resistance values of RP1 and RP2 in a digital potentiometer IC4, namely W1-V1 end resistance and W2-V2 end resistance.
Taking:
the working process of the invention is as follows:
as shown in fig. 1.
(1) Frequency-selecting resonance detection process: the 2 nd potentiometer RP2 in the digital potentiometer IC4 sheet outputs a resistance value RV1, a high-resistance operational amplifier IC1, a resonance operational amplifier IC2, a resonance capacitor C1, a resonance resistor R1 and the like to form an equivalent numerical control resonance capacitor (for short, the equivalent capacitor C is the equivalent capacitor C1)ie) The circuit is shown as formula (2). Equivalent capacitance CieForming a resonant circuit with the induction coil CS1 at the selected frequency, the corresponding resonant frequency is as shown in formula (1), and the output of the high-resistance operational amplifier IC1And the output end OUT is the output end of the numerical control resonant circuit. Wherein, the 2 nd potentiometer RP2 in the digital potentiometer IC4 outputs a resistance RV2 from the I end of the serial clock end SCL end and the serial data end SCA end of the superior controller through the connecting piece CN12And C, controlling by using a bus signal.
(2) And (3) output signal conditioning process: the resonance signal output by the output end OUT of the high-impedance operational amplifier IC1 passes through a negative end resistor R2, an output operational amplifier IC3, a1 st potentiometer RP1 in a digital potentiometer IC4 chip to output a resistance value RV1 and the like to form an output signal conditioning circuit, and the amplitude of the output signal can be adjusted by changing the resistance value RV1 as shown in a formula (3). Wherein, the 1 st potentiometer RP1 in the digital potentiometer IC4 outputs a resistance RV1 from the I end of the serial clock end SCL end and the serial data end SCA end of the superior controller through the connecting piece CN12And C, controlling by using a bus signal.
Claims (2)
1. The utility model provides an induction coil signal receiving circuit based on numerical control resonant frequency which characterized in that:
an induction coil signal receiving circuit based on numerical control resonant frequency comprises a connecting piece CN1, an induction coil CS1, a high-resistance operational amplifier IC1, a resonant operational amplifier IC2, an output operational amplifier IC3, a digital potentiometer IC4, coil internal resistance R0, a coil inductor L0, a resonant resistor R1, a negative end resistor R2, a resonant capacitor C1, a positive power supply capacitor C2 and a negative power supply capacitor C3, wherein a coil internal resistance R0, a coil inductor L0 and a voltage induction signal source u are arranged inside the induction coil CS1sThe three are connected IN series, one end of an induction coil CS1 is grounded, the other end of the induction coil CS1 is connected with one end of a resonant capacitor C1 and the positive input end IN + end of a high-resistance operational amplifier IC1, the output end OUT end of the high-resistance operational amplifier IC1 is connected with the negative input end IN-end of the high-resistance operational amplifier IC1, one end of a resonant resistor R1 and one end of a negative end resistor R2, the positive power end + V end of the high-resistance operational amplifier IC1 is connected with the positive power end + VCC end of the circuit, the negative power end-V end of the high-resistance operational amplifier IC1 is connected with the negative-VSS end of the circuit, the other end of the resonant resistor R1 is connected with the negative input end IN-end of the resonant operational amplifier IC2, the upper end RH2 end and the central end RW2 end of the 2 nd potentiometer IC4, the output end OUT end of the resonant operational amplifier IC2 is connected with the RL2 end of the 2 nd end of the digital potentiometer IC4, the resonant capacitor C1The positive input end IN + end of the resonant operational amplifier IC2 is grounded, the positive power end + V end of the resonant operational amplifier IC2 is connected with the positive power end + VCC end of the circuit, the negative power end-V end of the resonant operational amplifier IC2 is connected with the negative power end-VSS end of the circuit, the other end of the negative end resistor R2 is connected with the negative input end IN-end of the output operational amplifier IC3 and the lower end RL1 of the 1 st potentiometer of the digital potentiometer IC4, the output end OUT end of the output operational amplifier IC3 is connected with the upper end RH1 end of the 1 st potentiometer of the digital potentiometer IC4, the center end RW1 and the output signal end Uout end of the connecting piece CN1, the positive input end IN + end of the output operational amplifier IC3 is grounded, the positive power end + V end of the output operational amplifier IC3 is connected with the positive power end VCC end, the negative power end-V end of the output operational amplifier IC3 is connected with the negative power end-VSS end of the circuit, the positive power end VCC end of the digital potentiometer IC4 is connected with the positive power end VCC circuit, the ground terminal GND of the digital potentiometer IC4 is grounded, the unit address terminal a0 of the digital potentiometer IC4, the ten-bit address terminal a1 of the digital potentiometer IC4, the hundred-bit address terminal a2 of the digital potentiometer IC4, and the thousand-bit address terminal A3 of the digital potentiometer IC4 are all grounded, the serial clock terminal SCL of the digital potentiometer IC4 is connected to the clock terminal SCL of the connection CN1, the serial data terminal SDA of the digital potentiometer IC4 is connected to the data terminal SDA of the connection CN1, the positive power terminal VCC of the connection CN1 is connected to the positive power terminal + VCC of the circuit and one terminal of the positive power capacitor C2, the negative power terminal VSS of the connection CN1 is connected to the negative power terminal + VSS of the circuit and one terminal of the negative power capacitor C3, and the ground terminal of the connection CN1 is connected to the other terminal of the positive power capacitor C2 and the other terminal of the negative power capacitor C3.
2. The digital control resonant frequency based induction coil signal receiving circuit of claim 1, wherein the circuit parameters are in the following relationship:
setting: u. ofs、UsmaxFor the open-loop voltage signal of the induction coil and its maximum amplitude, Us(j ω) is usA complex domain signal of (a); u. ofiFor outputting voltage signals to the induction coil, Ui(j ω) is uiA complex domain signal of (a); i.e. iiFor the current signal output of the induction coil uout、UoutmaxFor circuit transmissionOutput signal and its maximum amplitude, Uout(j ω) is uoutA complex domain signal of (a); omega is angular frequency of induction signal, omega belongs to [ omega ]min，ωmax]，R0Is the internal resistance of the induction coil, L0The inductance of the induction coil is RP1 and RP2 which are respectively the rated resistance values of two numerical control potentiometers in the digital potentiometer IC4,
resonance frequency:
equivalent capacitance:
output signal at resonance:
RV1 and RV2 in the formula are respectively the output resistance values of RP1 and RP2 in a digital potentiometer IC4, namely RV1 is the resistance between an RW1 end and an RL1 end in RP1, RV2 is the resistance between an RW2 end and an RL2 end in RP2
Taking:
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| CN109696939A (en) * | 2017-10-23 | 2019-04-30 | 四川农业大学 | A kind of digital-control constant-flow source control loop |
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| US6349116B1 (en) * | 1999-10-14 | 2002-02-19 | Wherenet Corp. | Data communication system harnessing frequency shift keyed magnetic field |
| US6339368B1 (en) * | 2000-03-31 | 2002-01-15 | Zilog, Inc. | Circuit for automatically driving mechanical device at its resonance frequency |
| JP4449383B2 (en) * | 2003-09-24 | 2010-04-14 | セイコーエプソン株式会社 | Oscillator circuit |
| CN104807524B (en) * | 2015-05-08 | 2017-04-26 | 重庆大学 | Adjustable-amplitude quartz crystal microbalance self-excited oscillation circuit |
| CN204559556U (en) * | 2015-05-12 | 2015-08-12 | 王韬 | A kind of shifting demodulation circuit |
| CN108931665B (en) * | 2018-05-21 | 2020-11-20 | 东南大学 | Digital phase-locked measurement and control circuit for silicon micro-resonant accelerometer |
| CN108627570B (en) * | 2018-05-24 | 2022-05-17 | 北京工业大学 | Digital harmonic excitation source and implementation method |
| CN112003579B (en) * | 2020-08-26 | 2021-04-27 | 广西电网有限责任公司电力科学研究院 | Thing networking signal transmission noise reduction system |
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|---|---|---|---|---|
| CA2635711A1 (en) * | 2005-12-29 | 2007-07-19 | Knorr-Bremse Systeme Fuer Nutzfahrzeuge Gmbh | Analysis and compensation circuit for an inductive displacement sensor |
| CN102013868A (en) * | 2010-11-30 | 2011-04-13 | 中山大学 | Numerical control variable inductance |
| CN109696939A (en) * | 2017-10-23 | 2019-04-30 | 四川农业大学 | A kind of digital-control constant-flow source control loop |
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