CN108900194A - A kind of power frequency conversion circuit that programmable multi-threshold compares - Google Patents
A kind of power frequency conversion circuit that programmable multi-threshold compares Download PDFInfo
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- CN108900194A CN108900194A CN201811123272.5A CN201811123272A CN108900194A CN 108900194 A CN108900194 A CN 108900194A CN 201811123272 A CN201811123272 A CN 201811123272A CN 108900194 A CN108900194 A CN 108900194A
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- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03M—CODING; DECODING; CODE CONVERSION IN GENERAL
- H03M1/00—Analogue/digital conversion; Digital/analogue conversion
- H03M1/06—Continuously compensating for, or preventing, undesired influence of physical parameters
- H03M1/0617—Continuously compensating for, or preventing, undesired influence of physical parameters characterised by the use of methods or means not specific to a particular type of detrimental influence
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Abstract
The invention discloses a kind of power frequency conversion circuits that programmable multi-threshold compares, including integrating circuit, programmable multi-threshold comparison circuit, constant-current source, switching circuit and interface circuit;The current signal of input is converted to voltage signal by integrating circuit in real time, it is input to programmable multi-threshold comparison circuit, voltage value and voltage change trend are compared, judged and compensated by programmable multi-threshold comparison circuit, and it exports to interface circuit, when integrating circuit charge reaches balance, constant-current source is controlled by switching circuit, reverse charging is carried out to integrating circuit, until integrating circuit output voltage signal meets the determination requirement of programmable multi-threshold comparison circuit.The current frequency converter circuit that programmable multi-threshold of the invention compares solves the disadvantage that existing power frequency conversion sample rate is low, the difficult raising of precision, can be used for the occasion more demanding to power frequency conversion accuracy.
Description
Technical field
The present invention relates to a kind of current frequency converter circuit, especially a kind of power frequency that programmable multi-threshold compares
Converter circuit.
Background technique
In some inertial navigation systems, posture is run for real-time detection, needs to acquire acceleration transducer output in real time
(Export electric current)Judging operating status, passing through steering engine and platform motor control and intervening the speed of service and path.
Currently, in inertial navigation system, the power frequency switch technology acquired comparative maturity is exported for acceleration, and
And it can achieve relatively high accuracy.Existing power frequency technology, realizes transformation function by discrete device, develops to CPLD/
FPGA accurately controls miniaturization, and constant-current source is modular integrated, the real-time compensation of digital analog converter and digital signal processor,
It has been made great progress that, while bringing certain difficulty to later innovation and development.
As the demand of weapon attack precision improves, higher want is proposed to the current frequency converter for attitude measurement
It asks.Current frequency converter has a degree of raising from discrete device to digital compensation, but is not able to satisfy still more high-precision
The use demand of degree.
Summary of the invention
Low, the difficult raising of precision that the object of the invention is to the sample rates in order to solve existing current frequency converter circuit
The disadvantages of, a kind of current frequency converter circuit that programmable multi-threshold compares is provided.
The technical solution for realizing the aim of the invention is as follows:
A kind of current frequency converter circuit that programmable multi-threshold compares, which is characterized in that including integrating circuit, programmable more
5 part such as thresholding comparison circuit, constant-current source circuit, switching circuit, interface circuit;
The current signal of input can be converted in real time voltage signal by integrating circuit, be input to programmable multi-threshold comparison circuit,
Previous threshold voltage and the voltage value handled are compared by programmable multi-threshold comparison circuit, interface electricity is given in compensated output
Road;When multi-threshold comparison circuit judges that integrating circuit charge reaches balance, by control switch circuit control constant-current source to integral
Circuit carries out reverse charging, until integrating circuit output voltage is lower than programmable multi-threshold comparison circuit minimum threshold.
Integrating circuit core devices are operational amplifier, further include that the peripheral circuits such as capacitor are constituted.General amplifier is not
It is able to satisfy requirement, circuit itself have to can carry out self-correcting to zero-bit and drift.In order to improve the precision of converter,
Reduce zero drift, the noise generated due to amplifier drift when small signal being inhibited to input has selected copped wave Auto zeroing amplifier
ICL7650, it is the chopper-zero-stabilized high-operational amplifier integrated using CMOS technique, input resistance 1012Ω, bias current exist
It is 4pA at 25 °C, input offset voltage is 1 μ V, and common-mode rejection ratio 140dB, gain 150dB, property favorable rates is honest and clean, especially has
The no auto-zero advantage of other high resistant amplifiers is well suited for making the integrating circuit of I/F converter.
The major function of constant-current source is to provide reference current, since power frequency conversion circuit is according to electric quantity balancing original
Reason carries out precise quantification, and it is most important part in circuit design that the variation of constant-current source, which influences maximum to the performance of conversion circuit,
One of.Influencing crucial device to reference current is pressure stabilizing a reference source and precision resistance, and pressure stabilizing benchmark selects LM199AH, long
Time stability representative value is 2 × 10- 5/ 1000h.
Switching circuit core devices are analog switch, according to integrated demand, select ADG1421BRMZ.
Interface circuit includes RS422 level shifting circuit, RS422 level shifting circuit and isolation and level shifting circuit packet
RS422 level shifting circuit, RS422 level shifting circuit and isolation and level shifting circuit are included, main realization frequency signal
Pass through interactive correspondence of RS422 interface etc. by RS422 interface numeral output, the output of frequency signal, configuration information.
Programmable multi-threshold comparison circuit includes power converting system, digital analog converter and processor;It realizes to integral electricity
Multiple repairing weld, analysis, judgement and output in road output signal each period.
The multiple power supplies signal of input is converted to through power converting system to be suitable for being supplied to digital analog converter and processor
Electricity;The voltage signal of integrating circuit output input processor after digital analog converter is converted to analog signal;It is handled through processor
After export to interface circuit.
Processor is exported has configuration/output UART0 interface, configuration/output to be connect with UART1 to the signal of interface circuit
Mouth, original pulse output interface, extension pulse output interface, overcurrent warning output, transition status show output signal.
The beneficial effects obtained by the present invention are as follows:
The current frequency converter circuit that programmable multi-threshold of the invention compares solves existing power frequency conversion sampling
The shortcomings that rate is low, precision difficult raising, can be used for the occasion more demanding to power frequency conversion accuracy.
Detailed description of the invention
Fig. 1 is a kind of circuit block diagram for the current frequency converter circuit that programmable multi-threshold compares of the present invention.
Fig. 2 is that a kind of programmable multi-threshold for the current frequency converter circuit that programmable multi-threshold compares of the present invention compares
Schematic block circuit diagram.
Fig. 3 is a kind of interface circuit principle frame for the current frequency converter circuit that programmable multi-threshold compares of the present invention
Figure.
Fig. 4 is that a kind of programmable multi-threshold for the current frequency converter circuit that programmable multi-threshold compares of the present invention compares
Power converting system Some principles Fig. 1 in circuit.
Fig. 5 is that a kind of programmable multi-threshold for the current frequency converter circuit that programmable multi-threshold compares of the present invention compares
Power converting system Some principles Fig. 2 in circuit.
Fig. 6 is that a kind of programmable multi-threshold for the current frequency converter circuit that programmable multi-threshold compares of the present invention compares
Digital analog converter partial schematic diagram in circuit.
Fig. 7 is that a kind of programmable multi-threshold for the current frequency converter circuit that programmable multi-threshold compares of the present invention compares
Technical thought.
Fig. 8 is a kind of current frequency converter circuit programming rule that programmable multi-threshold compares of the present invention and truth table.
Specific embodiment
Below in conjunction with attached drawing, the embodiment of this programme is described in detail.
As shown in Figure 1, a kind of power frequency conversion circuit that programmable multi-threshold compares of the present invention, by integrating circuit 1, more
Thresholding comparison circuit 2, constant-current source circuit 3, switching circuit 4, interface circuit 5 form.
It as shown in Figure 2, is 2 functional block diagram of multi-threshold comparison circuit, by power converting system, digital analog converter, processor
Circuit composition.Input signal has the voltage signal after multiple power supplies and integral;Multiple power supplies are converted to suitable through power converting system
It is powered in digital analog converter and processor.Voltage signal after integral is defeated after digital analog converter is converted to analog signal
Enter processor.Previous threshold voltage and the voltage value handled are compared by processor, judged, and according to voltage change trend
It nourishes and repays, export to interface circuit.Export has configuration/output UART0 interface, configuration/output to use to the signal of interface circuit
UART1 interface, original pulse output interface, extension pulse output interface, overcurrent warning output, transition status display output.
It as shown in Figure 3, is a kind of interface circuit 5 for the current frequency converter circuit that programmable multi-threshold compares of the present invention
Functional block diagram;RS232 level shifting circuit exports after the TTL signal of received UART0 interface is isolated;RS422 level
The TTL signal of received UART1 interface is converted to RS422 interface by conversion circuit;Isolation and level shifting circuit will be received
Original pulse, extension pulse, overcurrent warning corresponding digital signal are isolated and are exported after being protected.
It is the power converting system schematic diagram in programmable multi-threshold comparison circuit of the invention as shown in Fig. 4 and Fig. 5,
Two kinds of integrated circuits of LM5008 and LM1117 and several resistance, capacitor and inductance are mainly used.It is main to realize to supply voltage
Transformation is powered for late-class circuit.
As shown in Figure 6, it is digital analog converter schematic diagram in programmable multi-threshold comparison circuit of the invention, uses beauty
The digital analog converter AD7367-5 of ADI company of state, device ADC range ± 10V, sampling rate 500KHz, sampling precision 16,
Meet requirement, control mode is serial communication and synchronized sampling, can reduce circuit size.
It as shown in Figure 7, is the programmable multi-threshold comparison techniques thinking of the present invention.It works in prior art in integrator
Only progress thresholding is more primary in a cycle, and present invention employs multi-thresholds, and programmable, and sampling thresholding may be up to
1024, be 1024 times of existing scheme.
As shown in Figure 8, be a kind of current frequency converter circuit programming rule that programmable multi-threshold compares of the present invention and
Truth table, configuration-direct setting include frame head, mode, thresholding starting point, thresholding terminal, stepping, inspection and postamble.The present invention is only situated between
The shape of 00 * * * * * * * * * * * * XXXX 55 " of the relevant configuration-direct of the multi-threshold that continues programming, as configuration-direct is set as " AA
Formula is then to configure automatic mode for this current frequency converter thresholding, because converter inside integrator hardware determines that charge is flat
Weighing apparatus point is fixed, and software will be according to electric current input current size, power frequency, current step characteristic optimizing thresholding, thresholding width
Understand Automatic Optimal according to the actual situation.When electric current is constant, apart from voltage be 0V or charge balance point voltage when, in order to increase sampling
Precision, thresholding width can become smaller.When electric current is sinusoidal or step, software can be than increasing thresholding when stable state.
The above is only a preferred embodiment of the present invention, it is noted that for the ordinary skill people of the art
For member, without departing from the technical principles of the invention, several improvement and deformations can also be made, these improvement and deformations
Also it should be regarded as protection scope of the present invention.
Claims (7)
1. a kind of power frequency conversion circuit that programmable multi-threshold compares, characterized in that including integrating circuit, may be programmed more
Limit comparison circuit, constant-current source, switching circuit and interface circuit;
The current signal of input is converted to voltage signal by integrating circuit in real time, is input to programmable multi-threshold comparison circuit, by
Programmable multi-threshold comparison circuit is compared previous threshold voltage and the voltage value handled, and compensated output is to interface
Circuit;When integrating circuit charge reaches balance, constant-current source is controlled by switching circuit, reverse charging is carried out to integrating circuit, directly
It is lower than programmable multi-threshold comparison circuit minimum threshold to integrating circuit output voltage.
2. the power frequency conversion circuit that a kind of programmable multi-threshold according to claim 1 compares, characterized in that integral
Circuit includes copped wave Auto zeroing operational amplifier ICL7650.
3. the power frequency conversion circuit that a kind of programmable multi-threshold according to claim 1 compares, characterized in that constant current
Source is used to provide reference current to integrating circuit.
4. the power frequency conversion circuit that a kind of programmable multi-threshold according to claim 1 compares, characterized in that switch
Circuit uses analog switch ADG1421BRMZ.
5. the power frequency conversion circuit that a kind of programmable multi-threshold according to claim 1 compares, characterized in that can compile
Journey multi-threshold comparison circuit includes power converting system, digital analog converter and processor;
The multiple power supplies signal of input is converted to through power converting system to be suitable for being powered to digital analog converter and processor;Product
The voltage signal of parallel circuit output input processor after digital analog converter is converted to analog signal;It is exported after processor is handled
To interface circuit.
6. the power frequency conversion circuit that a kind of programmable multi-threshold according to claim 5 compares, characterized in that processing
Device is exported has configuration/output UART0 interface, configuration/output UART1 interface, original pulse defeated to the signal of interface circuit
Outgoing interface, extension pulse output interface, overcurrent warning output, transition status show output signal.
7. the power frequency conversion circuit that a kind of programmable multi-threshold according to claim 6 compares, characterized in that interface
Circuit includes RS422 level shifting circuit, RS422 level shifting circuit and isolation and level shifting circuit.
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Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN110058078A (en) * | 2019-05-23 | 2019-07-26 | 上海仁机仪器仪表有限公司 | A kind of current measurement circuit and measurement method based on I-F transformation |
CN110572157A (en) * | 2019-08-30 | 2019-12-13 | 中勍科技有限公司 | temperature compensation method for I/F conversion circuit board |
CN110868215A (en) * | 2019-12-10 | 2020-03-06 | 中国电子科技集团公司第四十三研究所 | Self-adaptive control high-precision current/frequency conversion circuit |
CN112398473A (en) * | 2020-11-05 | 2021-02-23 | 中国兵器工业集团第二一四研究所苏州研发中心 | Current frequency conversion circuit with self-adaptive multi-threshold comparison function |
CN114076847A (en) * | 2020-08-18 | 2022-02-22 | 航天科工惯性技术有限公司 | High-resolution current frequency conversion device and method |
CN115133934A (en) * | 2022-06-14 | 2022-09-30 | 中船航海科技有限责任公司 | High-precision low-power current frequency conversion circuit and conversion method |
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Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN110058078A (en) * | 2019-05-23 | 2019-07-26 | 上海仁机仪器仪表有限公司 | A kind of current measurement circuit and measurement method based on I-F transformation |
CN110572157A (en) * | 2019-08-30 | 2019-12-13 | 中勍科技有限公司 | temperature compensation method for I/F conversion circuit board |
CN110868215A (en) * | 2019-12-10 | 2020-03-06 | 中国电子科技集团公司第四十三研究所 | Self-adaptive control high-precision current/frequency conversion circuit |
CN110868215B (en) * | 2019-12-10 | 2024-02-09 | 中国电子科技集团公司第四十三研究所 | Self-adaptive control high-precision current/frequency conversion circuit |
CN114076847A (en) * | 2020-08-18 | 2022-02-22 | 航天科工惯性技术有限公司 | High-resolution current frequency conversion device and method |
CN112398473A (en) * | 2020-11-05 | 2021-02-23 | 中国兵器工业集团第二一四研究所苏州研发中心 | Current frequency conversion circuit with self-adaptive multi-threshold comparison function |
CN115133934A (en) * | 2022-06-14 | 2022-09-30 | 中船航海科技有限责任公司 | High-precision low-power current frequency conversion circuit and conversion method |
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