CN101140183B - Circuit for maintaining vibrating signal synchronous - Google Patents
Circuit for maintaining vibrating signal synchronous Download PDFInfo
- Publication number
- CN101140183B CN101140183B CN2007101758100A CN200710175810A CN101140183B CN 101140183 B CN101140183 B CN 101140183B CN 2007101758100 A CN2007101758100 A CN 2007101758100A CN 200710175810 A CN200710175810 A CN 200710175810A CN 101140183 B CN101140183 B CN 101140183B
- Authority
- CN
- China
- Prior art keywords
- circuit
- signal
- vibration signal
- output
- operational amplifier
- 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
Landscapes
- Measurement Of Mechanical Vibrations Or Ultrasonic Waves (AREA)
- Amplifiers (AREA)
Abstract
The invention relates to circuit for keeping a vibration signal synchronous, which comprises a signal terminal and a two-way circuit connected with the signal terminal, wherein one way is connected with an operational amplifier, the other way is connected with an optical coupling relay of port voltage controlled by a single chip machine, the output end of the optical coupling relay is connected with the input end of a signal selection circuit, the output end of the signal selection circuit is connected with the input end of a vibration signal conditioning circuit, the vibration signal conditioning circuit comprises a signal amplification circuit, a buffer circuit, a median operational circuit, a comparison circuit, a hysteresis circuit and a amplitude conditioning circuit which are orderly connected, and is connected with the single chip machine through the output signal of the amplitude conditioning circuit. The invention can be simultaneously connected with different types of eddy current sensors and magnetoresistive sensors without any hardware changes, and simultaneously can set the hysteresis circuit according to the condition software of field signal and improve the anti-interference performance of the circuit.
Description
Technical field
The present invention relates to the vibration analysis field tests, be specifically related to a kind of circuit that keeps vibration signal synchronous.
Background technology
At present, determine that sampled point generally has two kinds of methods when carrying out vibration-testing and analyzing, a kind of is fixed sampling frequency, and a kind of is the method for sampling with signal Synchronization, but circuit complexity, and keep at present in the circuit of vibration signal synchronous, a kind of circuit can only connect a kind of specific sensor, perhaps needs hardware jumper, increased the complicacy of circuit design, not only use inconvenience, and the cost height, make troubles for the test of daily vibration signal.
Summary of the invention
The purpose of this invention is to provide a kind of circuit that keeps vibration signal synchronous, this circuit need not be changed by any hardware, only signal conditioning circuit is selected in the control of several analog switches by software setting, can insert different sensor signals, and sampling resolution can be set, can adopt software setting signal zero return difference to improve the signal interference free performance simultaneously.
For achieving the above object, the present invention adopts following technical scheme:
A kind of circuit that keeps vibration signal synchronous, this circuit comprises signal terminal input end and the circuit that is connected with signal terminal, the described circuit that is connected with signal terminal is divided into two-way, one tunnel concatenation operation amplifier, one the tunnel connects the light coupling relay by its port voltage of Single-chip Controlling, the output terminal of described light coupling relay connects the signal selecting circuit input end, the output terminal of signal selecting circuit connects vibration signal modulate circuit input end, the vibration signal modulate circuit comprises the signal amplification circuit that connects successively, buffer circuit, the median computing circuit, comparator circuit, the hysteresis circuit, the amplitude modulate circuit is through the output signal access single-chip microcomputer of amplitude modulate circuit.
The method of the described light coupling relay port voltage of described Single-chip Controlling is: described single-chip microcomputer is put height according to the type of sensor that inserts described maintenance vibration signal synchronous circuit or is dragged down the control end level of described light coupling relay.
Two simulating signal roads that described signal selecting circuit is connected by several light coupling relay, with one of them light coupling relay select switch to form with the current-limiting resistance that is connected with each light coupling relay.
Described signal amplification circuit is made up of operational amplifier and build-out resistor.
Described signal amplification circuit output is divided into two-way, one the tunnel enters the signal input part of described comparator circuit, described buffer circuit is inserted on another road, the output of described buffer circuit inserts described median operation circuit, and the output of described median computing circuit inserts another signal input part of described comparator circuit.
Described hysteresis circuit is made of operational amplifier and digital regulation resistance, and the resistance of being controlled by digital regulation resistance connects described operational amplifier, regulates hysteresis voltage by regulating described digital regulation resistance.
Described amplitude modulate circuit is made up of with the Schmidt trigger that is connected with described divider resistance divider resistance.
The number of described vibration signal modulate circuit is 2, and the circuit structure of described 2 vibration signal modulate circuits is identical, and the control of 2 analog switches that connect by software setting pair and described signal selecting circuit selects to insert different vibration signal modulate circuits.
Be connected with operational amplifier in the middle of described median computing circuit and the described comparator circuit, the output of described median computing circuit inserts the input anode of described operational amplifier, the output terminal of described operational amplifier connects window comparator circuit, and the output terminal of described operational amplifier feeds back to the input negative terminal.
Described window comparator circuit is judged the size of the output end signal of connected operational amplifier, when signal magnitude is in the intermediate value of described window comparator circuit, be output as low level, when being greater than or less than the intermediate value of described window comparator circuit, be output as high level.
Utilize the present invention can insert dissimilar current vortex sensors and magnetoresistive transducer simultaneously, and need not change by any hardware, simultaneously can be according to the situation software setting hysteresis voltage of on-site signal, promptly regulate hysteresis voltage, improved the anti-interference of circuit by the output resistance that digital regulation resistance is set.
Description of drawings
Fig. 1 is divided into the partial circuit figure of a road the two-way after signal terminal enters for vibration signal of the present invention;
Fig. 2 keeps window comparator reference source circuit figure in the vibration signal synchronous circuit for the present invention;
Fig. 3 keeps the circuit diagram of the vibration signal modulate circuit passage one in the vibration signal synchronous circuit for the present invention;
Fig. 4 keeps the circuit diagram of the vibration signal modulate circuit passage two in the vibration signal synchronous circuit for the present invention;
Fig. 5 keeps the circuit diagram of the window comparator of interface channel one in the vibration signal synchronous circuit for the present invention;
Fig. 6 keeps the circuit diagram of the window comparator of interface channel two in the vibration signal synchronous circuit for the present invention;
Fig. 7 keeps the circuit diagram that is connected with window comparator in the vibration signal synchronous circuit for the present invention;
Fig. 8 is the circuit diagram of the digital regulation resistance that is connected with hysteresis circuit in the passage one in the circuit of the present invention;
Fig. 9 is the circuit diagram of the digital regulation resistance that is connected with hysteresis circuit in the passage two in the circuit of the present invention.
Embodiment
Following examples are used to illustrate the present invention, but are not used for limiting the scope of the invention.
A kind of circuit that keeps vibration signal synchronous, this circuit comprises signal terminal input end and the circuit that is connected with signal terminal, the described circuit that is connected with signal terminal is divided into two-way, one tunnel concatenation operation amplifier, one the tunnel connects the light coupling relay by its port voltage of Single-chip Controlling, the output terminal of described light coupling relay connects the signal selecting circuit input end, the output terminal of signal selecting circuit connects vibration signal modulate circuit input end, the vibration signal modulate circuit comprises the signal amplification circuit that connects successively, buffer circuit, the median computing circuit, comparator circuit, the hysteresis circuit, the amplitude modulate circuit is through the output signal access single-chip microcomputer of amplitude modulate circuit.
The method of the described light coupling relay port voltage of described Single-chip Controlling is: described single-chip microcomputer is put height according to the type of sensor that inserts described maintenance vibration signal synchronous circuit or is dragged down the control end level of described light coupling relay.
Several current-limiting resistances that two simulating signal roads that described signal selecting circuit is connected by several light coupling relay, with one of them light coupling relay select switch, be connected with several light coupling relay are formed.
Described signal amplification circuit is made up of operational amplifier and build-out resistor.
Described signal amplification circuit output is divided into two-way, one the tunnel enters the signal input part of described comparator circuit, described buffer circuit is inserted on another road, the output of described buffer circuit inserts described median operation circuit, and the output of described median operation circuit inserts another signal input part of described comparator circuit.
Described hysteresis circuit is made of operational amplifier and digital regulation resistance, and the resistance of being controlled by digital regulation resistance connects described operational amplifier, regulates hysteresis voltage by regulating described digital regulation resistance.
Described amplitude regulating circuit is made up of with the Schmidt trigger that is connected with described divider resistance divider resistance.
The number of described vibration modulate circuit is 2, and the circuit structures of described 2 vibration modulate circuits are identical, and the different vibration modulate circuit of access is selected in the control of 2 analog switches that connect by software setting pair and described signal selecting circuit.
Be connected with operational amplifier in the middle of described median circuit and the described comparator circuit, the output of described median circuit inserts the input anode of described operational amplifier, the output terminal of described operational amplifier connects window comparator circuit, and the output terminal of described operational amplifier feeds back to the input negative terminal.
Described window comparator circuit is judged the size of the output end signal of connected operational amplifier, when signal magnitude is in the intermediate value of described window comparator, be output as low level, when being greater than or less than the intermediate value of described window comparator, be output as high level.
The circuit diagram principle and the concrete course of work below in conjunction with the description of drawings present embodiment.
The present invention keeps the circuit of vibration signal synchronous, vibration signal is divided into two-way after signal terminal enters, one the tunnel cushions output through operational amplifier uses for other instrument measurements, one the road inserts the light coupling relay U13 by its port voltage of Single-chip Controlling, be illustrated in figure 1 as vibration signal of the present invention is divided into a road the two-way after signal terminal enters this circuit partial circuit figure, in circuit diagram shown in Figure 1, vibration signal output terminal IN_01 inserts the 6th pin and the 8th pin by the light coupling relay U13 of its port voltage of Single-chip Controlling, main control singlechip is that the current vortex sensor or the situation of magnetoresistive transducer are put height or dragged down the control end of light coupling relay according to the setting of sensor, the 5th pin of light coupling relay U13 inserts resistor voltage divider network, this resistor voltage divider network is by resistance R 28, resistance R 29 and capacitor C 8 are formed, and the 7th pin IN01_CC of the output IN01_WW of resistor voltage divider network and light coupling relay U13 inserts signal selecting circuit.
Be illustrated in figure 2 as the present invention and keep window comparator reference source circuit figure in the vibration signal synchronous circuit, comprise the corresponding pin that is connected with the 7th pin IN01_CC of the output IN01_WW of resistor voltage divider network and light coupling relay U13 among Fig. 1 in this circuit, and with the output IN01_WW of resistor voltage divider network and the 7th pin access signal selecting circuit of light coupling relay U13, this signal selecting circuit selects switch AD_TEST_1 by the simulation road, switch AD_TEST_2 and light coupling relay U17 are selected in the simulation road, light coupling relay U19, light coupling relay U27 among Fig. 3, current-limiting circuit R11, R13, R14, R15 forms, circuit among Fig. 2 also comprises and analog switch amount AD_TEST_1, switch AD_TEST_2 light coupling relay U26 that connects and the circuit part that can insert vibration modulate circuit passage two are selected in the simulation road, in the present embodiment can be by control to analog switch, select signal conditioning circuit, select admission passage one and the vibration signal that leads to 2.
Be illustrated in figure 3 as the circuit diagram that the present invention keeps vibration signal modulate circuit passage one in the vibration signal synchronous circuit, Fig. 4 keeps the circuit diagram of vibration signal modulate circuit passage two in the vibration signal synchronous for the present invention, passage one among Fig. 3 is identical with passage two circuit diagram structures among Fig. 4, the function of the realization of two passages is identical, the corresponding connection of the CH1_SEL of light coupling relay U17 end among CH1_SEL among Fig. 3 and Fig. 2, the corresponding connection of the CH2_SEL of light coupling relay U29 end among CH2_SEL among Fig. 4 and Fig. 2, two passages of design in circuit, can be implemented in the same circuit and can insert two sensors of various types simultaneously, also can design three or more passages as required.After the corresponding connection of CH1_SEL among the CH1_SEL of light coupling relay U17 in the signal selecting circuit among Fig. 2 end and Fig. 3 in the signal selecting circuit, insert the vibration signal modulate circuit behind the light coupling relay U27 of signal in signal selecting circuit, the vibration signal modulate circuit comprises signal amplification circuit, buffer circuit, median computing circuit, comparator circuit, hysteresis circuit, the amplitude modulate circuit that connects successively, through the output signal access single-chip microcomputer of amplitude modulate circuit.
The flow process of signal in the vibration signal modulate circuit is as described in Figure 2: signal is the entering signal amplifying circuit at first, and signal amplification circuit is made of operational amplifier U18A and build-out resistor, and operational amplifier amplifies vibration signal; The output terminal 1 of signal amplification circuit is divided into two-way, and one the tunnel enters the signal input part of comparator circuit, and buffer circuit is inserted on another road, and this buffer circuit is made of operational amplifier U18B; Buffering output inserts the median computing circuit, and this median computing circuit is made up of schottky diode D10, D11,1uF capacitor C 12, C13,1nF capacitor C 14; The median of median computing circuit output signal is through operational amplifier U18C entering signal comparator circuit, this signal comparator circuit is made of operational amplifier U18D and build-out resistor thereof, the input anode of operational amplifier U18C is connected with the output terminal of median computing circuit, output terminal JX1 feedback is linked into the input negative terminal, be illustrated in figure 5 as the circuit diagram that the present invention keeps the window comparator that is connected with JX1 in the vibration signal synchronous circuit, Figure 6 shows that the present invention keeps the circuit diagram of the window comparator that is connected with JX2 in the vibration signal synchronous circuit, Fig. 7 keeps the circuit diagram that is connected with window comparator in the vibration signal synchronous circuit for the present invention, Vref0 among Fig. 7, the corresponding Vref0 of Vref01 and window comparator circuit shown in Figure 5, Vref01 connects, Vref0 among Fig. 7, the corresponding Vref0 of Vref02 and window comparator circuit shown in Figure 6, Vref02 connects, window comparator circuit is judged the size of the output end signal of connected operational amplifier, when signal magnitude is in the intermediate value of described window comparator, be output as lowly, when being greater than or less than the intermediate value of described window comparator, be output as height; Original signal is compared output pulse signal to the hysteresis circuit with the median signal, the hysteresis voltage of hysteresis circuit is adjustable, the hysteresis circuit totally keeps the digital regulation resistance XC9313 of vibration signal synchronous circuit to constitute by amplifier U16A and the present invention as shown in Figure 8, corresponding RH1 end among Fig. 8 among digital regulation resistance XC9313RH1 and Fig. 3 connects, and regulates hysteresis voltage by the resistance of regulating digital regulation resistance; The amplitude modulate circuit is inserted in hysteresis circuit output back, the amplitude modulate circuit is adjusted to 5V with the amplitude of pulse signal, this amplitude modulate circuit is made up of divider resistance R49, R50 and Schmidt trigger U20A, signal output DF1IN is input to the pin of single-chip microcomputer, and single-chip microcomputer is controlled the output acquisition pulse according to the cycle of signal and set frequency dividing ratio by the software of central control unit MCU.
Fig. 9 is the circuit diagram of the digital regulation resistance that is connected with hysteresis circuit in the passage two in the circuit of the present invention, and the corresponding RH2 end connection among Fig. 9 among digital regulation resistance XC9313RH2 and Fig. 4 is regulated hysteresis voltage by the resistance of adjusting digital regulation resistance.
Circuit of the present invention uses simple, need not any hardware change just can insert current vortex sensor and magnetoresistive transducer simultaneously, can improve the interference free performance of circuit according to the situation software setting hysteresis voltage of on-site signal simultaneously.
More than be preferred forms of the present invention, according to content disclosed by the invention, some identical, replacement schemes that those of ordinary skill in the art can expect apparently all should fall into the scope of protection of the invention.
Claims (9)
1. circuit that keeps vibration signal synchronous, this circuit comprises signal terminal input end and the circuit that is connected with signal terminal, it is characterized in that, the described circuit that is connected with signal terminal is divided into two-way, one tunnel concatenation operation amplifier, one the tunnel connects the light coupling relay by its port voltage of Single-chip Controlling, the output terminal of described light coupling relay connects the signal selecting circuit input end, the output terminal of signal selecting circuit connects vibration signal modulate circuit input end, the vibration signal modulate circuit comprises the signal amplification circuit that connects successively, buffer circuit, the median computing circuit, comparator circuit, the hysteresis circuit, the amplitude modulate circuit is through the output signal access single-chip microcomputer of amplitude modulate circuit; The number of described vibration signal modulate circuit is 2, and the circuit structure of described 2 vibration signal modulate circuits is identical, and the control of 2 analog switches that connect by software setting pair and described signal selecting circuit selects to insert different vibration signal modulate circuits.
2. the circuit of maintenance vibration signal synchronous as claimed in claim 1 is characterized in that the method for the described light coupling relay port voltage of described Single-chip Controlling is: described single-chip microcomputer is put height according to the type of sensor that inserts described maintenance vibration signal synchronous circuit or is dragged down the control end level of described light coupling relay.
3. the circuit of maintenance vibration signal synchronous as claimed in claim 2 is characterized in that two simulating signal roads that described signal selecting circuit is connected by several light coupling relay, with one of them light coupling relay select switch to form with the current-limiting resistance that is connected with each light coupling relay.
4. the circuit of maintenance vibration signal synchronous as claimed in claim 3 is characterized in that described signal amplification circuit is made up of operational amplifier and build-out resistor.
5. the circuit of maintenance vibration signal synchronous as claimed in claim 4, it is characterized in that described signal amplification circuit output is divided into two-way, one the tunnel enters the signal input part of described comparator circuit, described buffer circuit is inserted on another road, the output of described buffer circuit inserts described median computing circuit, and the output of described median computing circuit inserts another signal input part of described comparator circuit.
6. the circuit of maintenance vibration signal synchronous as claimed in claim 5, it is characterized in that described hysteresis circuit is made of operational amplifier and digital regulation resistance, resistance by digital regulation resistance control connects described operational amplifier, regulates hysteresis voltage by regulating described digital regulation resistance.
7. maintenance vibration signal synchronous circuit as claimed in claim 6 is characterized in that described amplitude modulate circuit is made up of with the Schmidt trigger that is connected with described divider resistance divider resistance.
8. maintenance vibration signal synchronous circuit as claimed in claim 1, it is characterized in that being connected with operational amplifier in the middle of described median computing circuit and the described comparator circuit, the output of described median computing circuit inserts the input anode of described operational amplifier, the output terminal of described operational amplifier connects comparator circuit, and the output terminal of described operational amplifier feeds back to the input negative terminal.
9. maintenance vibration signal synchronous circuit as claimed in claim 8, it is characterized in that described comparator circuit judges the size of the output end signal of connected operational amplifier, when signal magnitude is in the intermediate value of described comparator circuit, be output as low level, when being greater than or less than the intermediate value of described comparator circuit, be output as high level.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2007101758100A CN101140183B (en) | 2007-10-12 | 2007-10-12 | Circuit for maintaining vibrating signal synchronous |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2007101758100A CN101140183B (en) | 2007-10-12 | 2007-10-12 | Circuit for maintaining vibrating signal synchronous |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN101140183A CN101140183A (en) | 2008-03-12 |
| CN101140183B true CN101140183B (en) | 2010-04-14 |
Family
ID=39192228
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2007101758100A Expired - Fee Related CN101140183B (en) | 2007-10-12 | 2007-10-12 | Circuit for maintaining vibrating signal synchronous |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN101140183B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101882925A (en) * | 2010-07-02 | 2010-11-10 | 北京联合大学生物化学工程学院 | Any level hysteresis voltage comparator with adjustable return difference voltage |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102221401B (en) * | 2011-04-15 | 2013-01-09 | 易孟良 | Vibration test stand and testing method for vibration sensor |
| CN104101365B (en) * | 2014-07-09 | 2016-04-06 | 江西省智成测控技术研究所有限责任公司 | A kind of hysteresis logic realization method that return difference is adjustable and implement device |
| CN112104329B (en) * | 2020-09-22 | 2021-03-30 | 山东维平信息安全测评技术有限公司 | Thing networking data security signal calibration system |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CA2149991A1 (en) * | 1994-08-04 | 1996-02-05 | Emanuil Augustin Huluta | Multichannel equipment for signal acquisition from vibration transducers |
| CN2750390Y (en) * | 2004-09-24 | 2006-01-04 | 中国人民解放军国防科学技术大学 | Vibration remote monitoring device |
| CN2777610Y (en) * | 2005-01-07 | 2006-05-03 | 天津轻工职业技术学院 | On line monitor in training system of numerically controlled machine tool |
| CN2811952Y (en) * | 2005-06-13 | 2006-08-30 | 夏惠兴 | Online monitoring and protecting device for rotary machinery |
| CN2824176Y (en) * | 2005-05-23 | 2006-10-04 | 湖南科技大学 | High-integrated portable vibration signal treater |
| CN1333243C (en) * | 2004-06-15 | 2007-08-22 | 东北师范大学 | Dynamic measuring system with four sensors for acoustic field spacial distribution of acho signals of bat |
-
2007
- 2007-10-12 CN CN2007101758100A patent/CN101140183B/en not_active Expired - Fee Related
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CA2149991A1 (en) * | 1994-08-04 | 1996-02-05 | Emanuil Augustin Huluta | Multichannel equipment for signal acquisition from vibration transducers |
| CN1333243C (en) * | 2004-06-15 | 2007-08-22 | 东北师范大学 | Dynamic measuring system with four sensors for acoustic field spacial distribution of acho signals of bat |
| CN2750390Y (en) * | 2004-09-24 | 2006-01-04 | 中国人民解放军国防科学技术大学 | Vibration remote monitoring device |
| CN2777610Y (en) * | 2005-01-07 | 2006-05-03 | 天津轻工职业技术学院 | On line monitor in training system of numerically controlled machine tool |
| CN2824176Y (en) * | 2005-05-23 | 2006-10-04 | 湖南科技大学 | High-integrated portable vibration signal treater |
| CN2811952Y (en) * | 2005-06-13 | 2006-08-30 | 夏惠兴 | Online monitoring and protecting device for rotary machinery |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101882925A (en) * | 2010-07-02 | 2010-11-10 | 北京联合大学生物化学工程学院 | Any level hysteresis voltage comparator with adjustable return difference voltage |
| CN101882925B (en) * | 2010-07-02 | 2012-06-20 | 北京联合大学生物化学工程学院 | Any level hysteresis voltage comparator with adjustable return difference voltage |
Also Published As
| Publication number | Publication date |
|---|---|
| CN101140183A (en) | 2008-03-12 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101277066B (en) | Multipath voltage regulation insulation type digital DC/DC power supply as well as control method | |
| CN201993124U (en) | Multi-channel physical quantity measuring device | |
| CN101140183B (en) | Circuit for maintaining vibrating signal synchronous | |
| CN101119115A (en) | Multi-channel A/D conversion device and method | |
| CN103698594A (en) | Detection range-adjustable current detection circuit and method | |
| CN107623968A (en) | Line voltage compensation circuit, LED drive system and driving method | |
| CN102353836A (en) | Method for dynamically adjusting current channel gain of wide-range electric energy meter | |
| CN102393484A (en) | Device for detecting stability of current | |
| CN204667117U (en) | A kind of based on the adaptive analog quantity detecting device of general A/D sensing range | |
| CN2938573Y (en) | Multi-channel analog-digital conversion device | |
| CN1928574A (en) | Traveling wave accidents distance measuring device for hour and minute composite sampling electric transmission line | |
| CN108020727B (en) | Capacitor voltage conversion circuit | |
| CN100381955C (en) | System and method for calibrating analog signal measuring apparatus automatically | |
| CN201607486U (en) | Digital frequency characteristic tester | |
| CN202018478U (en) | Wide-range electric energy metering device for fluctuating load | |
| CN207083253U (en) | A kind of adaptive fast response circuit and LED drive circuit | |
| CN203881815U (en) | Simple high-precision DC electronic load | |
| CN110146297B (en) | Sensor power supply and data acquisition circuit and gas turbine generator set | |
| CN109916805A (en) | A kind of pressure control circuit of the fluid modules based on flow cytometer | |
| CN105652941A (en) | device for reducing voltage drop by adjusting partial pressure ratio | |
| CN203443967U (en) | Automobile instrument speed acquisition system | |
| CN210323186U (en) | Current detection circuit | |
| CN102706932A (en) | Circuit and method for adapting forward/reverse current of electrochemical gas sensor | |
| CN105934886B (en) | Semiconductor switch and for determining the method by the electric current of semiconductor switch | |
| CN106249040B (en) | Wide-range dynamic voltage measuring circuit and method |
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 | ||
| C17 | Cessation of patent right | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20100414 Termination date: 20121012 |