CN203688696U - Volt-ampere characteristic tester - Google Patents
Volt-ampere characteristic tester Download PDFInfo
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- CN203688696U CN203688696U CN201320893243.3U CN201320893243U CN203688696U CN 203688696 U CN203688696 U CN 203688696U CN 201320893243 U CN201320893243 U CN 201320893243U CN 203688696 U CN203688696 U CN 203688696U
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- test port
- couple
- switching tube
- sampling resistor
- volt
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- 238000012360 testing method Methods 0.000 claims abstract description 164
- 238000005070 sampling Methods 0.000 claims abstract description 69
- 230000008878 coupling Effects 0.000 claims description 9
- 238000010168 coupling process Methods 0.000 claims description 9
- 238000005859 coupling reaction Methods 0.000 claims description 9
- 238000010586 diagram Methods 0.000 description 9
- 239000004020 conductor Substances 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
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Abstract
A volt-ampere characteristic tester comprises a controller, a digital analog converter, an operational amplifier, a switch tube, a sampling resistor, a test port and an analog digital converter. The controller is coupled with the digital analog converter and the analog digital converter, the first input end of the operational amplifier is coupled with the digital analog converter, and the second input end is coupled with the sampling resistor. The output end of the operational amplifier is coupled with a control electrode of the switch tube, the switch tube is in series connection with the test port and the sampling resistor, and one end of the test port is coupled with the analog digital converter. By the volt-ampere characteristic tester, the efficiency of a volt-ampere characteristic test can be improved effectively.
Description
Technical field
The utility model relates to electron device testing field, relates in particular to a kind of Testing Instrument for Volt-ampere Characteristic.
Background technology
Volt-ampere characteristic refers to and is added in electrical equipment or element both end voltage and by the relation of electric current, volt-ampere characteristic is often used to study the Changing Pattern of conductor resistance, is one of conventional image method of physics.
Existing Testing Instrument for Volt-ampere Characteristic is simple in structure, but needs manual operation test, easily makes mistakes and inefficiency.
Utility model content
The problem that the utility model embodiment solves is how to improve the efficiency of volt-ampere characteristic test.
For addressing the above problem, the utility model embodiment provides a kind of Testing Instrument for Volt-ampere Characteristic, comprising: controller, digital to analog converter, operational amplifier, switching tube, sampling resistor, test port and analog to digital converter; Described controller and described digital to analog converter and described analog to digital converter couple, the first input end of described operational amplifier and described digital to analog converter couple, the second input end and the described sampling resistor of described operational amplifier couple, the control utmost point of the output terminal of described operational amplifier and described switching tube couples, described switching tube is connected with described test port and described sampling resistor, and one end of described test port and described analog to digital converter couple.
Optionally, described switching tube is NMOS pipe or PMOS pipe.
Optionally, described switching tube is NMOS pipe, the first end of described test port and default positive supply couple, the second end of described test port and second utmost point of described switching tube couple, first utmost point of described sampling resistor first end and described switching tube couples, described sampling resistor the second end ground connection, the second end and the described analog to digital converter of described test port couple.
Optionally, described switching tube is NMOS pipe, second utmost point of described switching tube and described default positive supply couple, first utmost point of described switching tube and the first end of described test port couple, the second end of the first end of described sampling resistor and described test port couples, the second end ground connection of described sampling resistor, the first end of described test port and described analog to digital converter couple.
Optionally, described switching tube is PMOS pipe, the first end of described sampling resistor and default positive supply couple, the second end of described sampling resistor and first utmost point of described switching tube couple, second utmost point of described test port first end and described switching tube couples, the second end ground connection of described test port, the first end of described test port and described analog to digital converter couple.
Optionally, described switching tube is PMOS pipe, the first end of described sampling resistor and default positive supply couple, the second end of described sampling resistor and the first end of described test port couple, first utmost point of described switching tube and the second end of described test port couple, the second utmost point ground connection of described switching tube, the second end and the described analog to digital converter of described test port couple.
Optionally, described Testing Instrument for Volt-ampere Characteristic also comprises: the storer coupling with described controller.
Optionally, described storer comprises following one: SD card, hard disk, EERROM, NOR Flash or Nand Flash.
Optionally, described Testing Instrument for Volt-ampere Characteristic also comprises: the display coupling with described controller.
Optionally, described display comprises following one: described display comprises following one: LCD display or light-emitting diode display, OLED display or CRT monitor.
Compared with prior art, the technical scheme of the utility model embodiment has the following advantages:
By the test port of element under test and tester is coupled, analog to digital converter and test port couple, obtain the magnitude of voltage of test port and send to controller, controller control digital to analog converter is exported different magnitudes of voltage, and the first input end of input operational amplifier, make operational amplifier output relevant voltage, the work of starting switch pipe, due to switching tube, sampling resistor and element under test series connection, switching tube, electric current on sampling resistor and element under test equates, can obtain the electric current on sampling resistor by the computing between the output voltage values of digital to analog converter and sampling resistor resistance, according to the magnitude of voltage of the test port obtaining, can obtain the pressure drop of element under test by computing, therefore utilize pressure drop and current value can obtain the volt-ampere characteristic of element under test.
Brief description of the drawings
Fig. 1 is the apparatus structure schematic diagram of a kind of Testing Instrument for Volt-ampere Characteristic in the utility model embodiment;
Fig. 2 is the circuit structure diagram of a kind of Testing Instrument for Volt-ampere Characteristic in the utility model embodiment;
Fig. 3 is the circuit structure diagram of the another kind of Testing Instrument for Volt-ampere Characteristic in the utility model embodiment;
Fig. 4 is the circuit structure diagram of other a kind of Testing Instrument for Volt-ampere Characteristic in the utility model embodiment;
Fig. 5 is the circuit structure diagram of a kind of Testing Instrument for Volt-ampere Characteristic in the utility model embodiment.
Embodiment
Existing Testing Instrument for Volt-ampere Characteristic relatively simple for structure, but need manual operation to carry out the test of volt-ampere characteristic, easily make mistakes and inefficiency.
For the problems referred to above, the utility model embodiment is by coupling the test port of element under test and tester, analog to digital converter and test port couple, obtain the magnitude of voltage of test port and send to controller, controller control digital to analog converter is exported different magnitudes of voltage, and the first input end of input operational amplifier, make operational amplifier output relevant voltage, the work of starting switch pipe, due to switching tube, sampling resistor and element under test series connection, switching tube, electric current on sampling resistor and element under test equates, can obtain the electric current on sampling resistor by the computing between the output voltage values of digital to analog converter and sampling resistor resistance, according to the magnitude of voltage of the test port obtaining, can obtain the pressure drop of element under test by computing, therefore utilize pressure drop and current value can obtain the volt-ampere characteristic of element under test.
For the above-mentioned purpose, the feature and advantage that make the utility model embodiment can more become apparent, below in conjunction with accompanying drawing, specific embodiment of the utility model is described in detail.
With reference to Fig. 1, the utility model embodiment provides a kind of structural representation of Testing Instrument for Volt-ampere Characteristic 10, comprising: controller 101, digital to analog converter 102, operational amplifier 103, switching tube 104, sampling resistor 105, test port 106 and analog to digital converter 107, wherein:
Described controller 101 couples with described digital to analog converter 102 and described analog to digital converter 107, the first input end of described operational amplifier 103 and described digital to analog converter 102 couple, the second input end and the described sampling resistor 105 of described operational amplifier 103 couple, the control utmost point of the output terminal of described operational amplifier 103 and described switching tube 104 couples, described switching tube 104 is connected with described test port 106 and described sampling resistor 105, and one end of described test port 106 and described analog to digital converter 107 couple.
In concrete enforcement, element under test can be placed in test port 106, element under test can be coupled with tester 10; Controller 101 can send the digital signal that comprises information of voltage to digital to analog converter 102, utilizes the Digital Signals digital to analog converter 102 that comprises different information of voltage to export different voltage; The output voltage of digital to analog converter 102 is input to the first input end of operational amplifier 103, because sampling resistor 105 and the second input end of operational amplifier 103 couple, utilize " empty short " of operational amplifier 103 and the characteristic of " empty disconnected " can obtain the electric current on sampling resistor 105, because switching tube 104 is connected with test port 106 and sampling resistor 105, the current value on switching tube 104, test port 106 and sampling resistor 105 equates.
Analog to digital converter 107 obtains the magnitude of voltage of test port 106, and by the magnitude of voltage input control device 101 of test port 106, controller 101 can be according to the pressure drop that calculates test port 106; Can obtain the voltage of test port 106 interior element under tests and the corresponding relation of electric current according to the current value of the pressure drop of test port 106 and test port 106.Control digital to analog converter 102 by controller 101 and export different voltage, can obtain many group voltage of element under test and the corresponding relation of electric current, can obtain the volt-ampere characteristic of element under test.
In concrete enforcement, described switching tube can comprise NMOS pipe or PMOS pipe.
In concrete enforcement, as shown in Figure 1, test port 106, switching tube 104 and sampling resistor 105 are connected, but the coupling mode of test port 106, switching tube 104 and sampling resistor 105 is not limited in the coupled in series mode described in Fig. 1, can also have other forms of coupling mode.Only need to meet the control utmost point of switching tube 104 with the output terminal of operational amplifier 103 couples, the second input end of sampling resistor 105 and operational amplifier 103 couples, and one end of test port 106 and analog to digital converter 107 couple, and do not repeat herein.
In concrete enforcement, test port can be the external interface of tester, also can be built in tester, does not repeat herein.Element under test can be placed in test port and test, and element under test can be resistance, can be also diode, can also be the element of other types.
The utility model embodiment is by coupling the test port of element under test and tester, analog to digital converter and test port couple, obtain the magnitude of voltage of test port and send to controller, controller control digital to analog converter is exported different magnitudes of voltage, and the first input end of input operational amplifier, make operational amplifier output relevant voltage, the work of starting switch pipe, due to switching tube, sampling resistor and element under test series connection, switching tube, electric current on sampling resistor and element under test equates, can obtain the electric current on sampling resistor by the computing between the output voltage values of digital to analog converter and sampling resistor resistance, according to the magnitude of voltage of the test port obtaining, can obtain the pressure drop of element under test by computing, therefore utilize pressure drop and current value can obtain the volt-ampere characteristic of element under test.
With reference to Fig. 2, the utility model embodiment provides a kind of circuit structure diagram of Testing Instrument for Volt-ampere Characteristic, comprising: controller 201, digital to analog converter 202, operational amplifier 203, switching tube 204, sampling resistor 205, test port 206 and analog to digital converter 207, wherein:
Controller 201 couples with digital to analog converter 202 and analog to digital converter 207; The first input end of operational amplifier 203 and digital to analog converter 202 couple, and the first end of the second input end and sampling resistor 205 couples, and the control utmost point of output terminal and switching tube 204 couples; The second input end of first utmost point of switching tube 204 and the first end of sampling resistor 205 and operational amplifier 203 couples, and the second end and the analog to digital converter 207 of second utmost point and test port 206 couple; The first end of test port 206 and default positive supply couple, the second end ground connection of sampling resistor 205.
In the utility model embodiment, before test starts, element under test can be put into test port, so that element under test is connected with tester; Default positive supply can be placed in Testing Instrument for Volt-ampere Characteristic, can be also external positive supply, and the magnitude of voltage of positive supply can be 12V, can be also other magnitudes of voltage, can choose according to actual needs.
In the utility model embodiment, controller 201 can send the digital signal that comprises information of voltage to digital to analog converter 202, utilizes the Digital Signals digital to analog converter 202 that comprises different information of voltage to export different magnitude of voltage V
rEF, by V
rEFthe first input end of input operational amplifier 203.
In the utility model embodiment, the first input end of operational amplifier 203 can be positive input terminal, and the second input end can be negative input end.By the positive input terminal of the output voltage input operational amplifier of digital to analog converter 202, the magnitude of voltage of positive input terminal is V
rEF, the magnitude of voltage of negative input end is V
-, the output voltage V of operational amplifier 203
1=k × (V
rEF-V
-), wherein, k can be the enlargement factor of operational amplifier 203.Operational amplifier 203 can also comprise positive power source terminal and negative power end, positive power source terminal can with default supply coupling, negative power end can ground connection.
In the utility model embodiment, can adopt NMOS pipe as switching tube 204.First of NMOS pipe 204 can be extremely source electrode, and second can be extremely drain electrode, and controlling can be extremely grid.The grid of NMOS pipe 204 and the output terminal of operational amplifier 203 couple, and the magnitude of voltage on the grid of NMOS pipe 204 is V
1.
In the utility model embodiment, the negative input end of the first end of sampling resistor 205 and operational amplifier 203 and the source electrode of NMOS pipe couple, the second end ground connection.From " empty short " characteristic of operational amplifier, in " empty short " situation, the potential difference (PD) between positive input terminal and the negative input end of operational amplifier is almost 0, and the magnitude of voltage of positive input terminal and negative input end is almost equal, V
-=V
rEF, the current value on sampling resistor 205 can be I
1=V
rEF/ R, wherein, R is the resistance value of sampling resistor 205.
Because NMOS pipe 204 is connected with sampling resistor 205, test port 206, and according to " empty disconnected " characteristic of operational amplifier 203, the current value of the negative input end of operational amplifier 203 is almost 0, negligible, NMOS pipe 204 equates with the electric current on sampling resistor 205, test port 206, and NMOS pipe 204 is I with the electric current on sampling resistor 205, test port 206
1.
In the utility model embodiment, the first end of test port 206 can couple with default positive supply VCC, and the second end can be managed 204 drain electrode and analog to digital converter 207 with NMOS and be coupled.Can adopt analog to digital converter 207 to obtain the magnitude of voltage V of test port 206 second ends
2, and by V
2convert digital signal to and send to controller 201.Controller 201 is according to VCC and V
2between difference, can obtain the pressure drop V of test port 206
3, V
3=VCC-V
2.According to V
3with I
1can obtain the volt-ampere characteristic of element under test in test port 206.
In the utility model embodiment, Testing Instrument for Volt-ampere Characteristic can also couple with storer 208, be used for storing the volt-ampere characteristic data of element under test, storer can be SD card, can be also the memory device of the other types such as hard disk, EERROM, NOR Flash or Nand Flash; Testing Instrument for Volt-ampere Characteristic also can couple with display 209, the volt-ampere characteristic of element under test is shown with the form of volt-ampere characteristic, display can be light-emitting diode display, also can be LCD display, the display of the other types such as all right OLED display or CRT monitor does not repeat herein.
With reference to Fig. 3, the utility model embodiment also provides the circuit structure diagram of another kind of Testing Instrument for Volt-ampere Characteristic, different from a upper utility model embodiment, and the position of the utility model embodiment to NMOS pipe and the position of test port are adjusted.
In the utility model embodiment, controller 301 couples with digital to analog converter 302 and analog to digital converter 307; The positive input terminal of operational amplifier 303 and digital to analog converter 302 couple, and the first end of negative input end and sampling resistor 305 and the second end of test port 306 couple, and the grid of output terminal and NMOS pipe 304 couples; The drain electrode of NMOS pipe and default positive supply couple, and first end and the analog to digital converter 307 of source electrode and test port 306 couple; The second end ground connection of sampling resistor 305.
In the utility model embodiment, identical with a upper utility model embodiment, the current value of test port 306 can be I
1=V
rEF/ R.Analog to digital converter 307 can obtain the magnitude of voltage V of the first end of test port 306
4, and by V
4convert digital signal to and send to controller 301.Controller 301 obtains the pressure drop V of test port 306
5, V
5=V
4-V
r.V
rfor the voltage on sampling resistor 305, V
r=V
rEF.According to V
5with I
1relation, can obtain the volt-ampere characteristic of element under test in test port 306.
In the utility model embodiment, can also adopt PMOS pipe as switching tube.
With reference to Fig. 4, the utility model embodiment provides the circuit structure diagram of another kind of Testing Instrument for Volt-ampere Characteristic, adopts PMOS pipe as switching tube.
In the utility model embodiment, controller 401 couples with digital to analog converter 402 and analog to digital converter 407; The positive input terminal of operational amplifier 403 and digital to analog converter 402 couple, and the second end of negative input end and sampling resistor 405 couples, and the grid of output terminal and PMOS pipe 404 couples; The source electrode of PMOS pipe 404 and the second end of sampling resistor 405 and the negative input end of operational amplifier 403 couple, and drain electrode couples with first end and the analog to digital converter 407 of test port 406; The second end ground connection of test port 406, the first end of sampling resistor 405 and default positive supply couple.
Because PMOS pipe 404, sampling resistor 405 and test port 406 are connected, equate the current value I of sampling resistor 405 with the current value of sampling resistor 405 with the current value on test port 406 in PMOS pipe 404
2=(VCC-V
rEF)/R.Be that current value on test port 406 is I
2.
In the utility model embodiment, analog to digital converter 407 couples with the first end of test port 406, and analog to digital converter 407 can obtain the magnitude of voltage V of test port 406 first ends
6, and by V
6convert digital signal to and send to controller 401.Controller 401 obtains the pressure drop of test port 406, and due to the second end ground connection of test port 406, the pressure drop of test port 406 is V
6.According to V
6with I
2relation, can obtain the volt-ampere characteristic of element under test in test port 406.
With reference to Fig. 5, the utility model embodiment yet provides the circuit structure diagram of another Testing Instrument for Volt-ampere Characteristic, different from a upper utility model embodiment, and the position of the utility model embodiment to PMOS pipe and the position of test port are adjusted.
In the utility model embodiment, controller 501 couples with digital to analog converter 502 and analog to digital converter 507; The positive input terminal of operational amplifier 503 and digital to analog converter 502 couple, and the second end of negative input end and sampling resistor 505 couples, and the grid of output terminal and PMOS pipe 504 couples; The second end of the first end of test port 506 and sampling resistor 505 and the negative input end of operational amplifier 503 couple, and source electrode and the analog to digital converter 507 of the second end and PMOS pipe 504 couple; The grounded drain of PMOS pipe 504, the first end of sampling resistor 505 and default positive supply couple.
In the utility model embodiment, identical with a upper utility model embodiment, the current value of test port 506 can be I
2=(VCC-V
rEF)/R.Analog to digital converter 507 can obtain the magnitude of voltage V of the second end of test port 506
7, and by V
7convert digital signal to and send to controller 501.Controller 501 obtains the pressure drop V of test port 506
8=V
rEF-V
7.According to V
8with I
2relation, can obtain the volt-ampere characteristic of element under test in test port 506.
Although the utility model discloses as above, the utility model is not defined in this.Any those skilled in the art, not departing from spirit and scope of the present utility model, all can make various changes or modifications, and therefore protection domain of the present utility model should be as the criterion with claim limited range.
Claims (10)
1. a Testing Instrument for Volt-ampere Characteristic, is characterized in that, comprising: controller, digital to analog converter, operational amplifier, switching tube, sampling resistor, test port and analog to digital converter; Described controller and described digital to analog converter and described analog to digital converter couple, the first input end of described operational amplifier and described digital to analog converter couple, the second input end and the described sampling resistor of described operational amplifier couple, the control utmost point of the output terminal of described operational amplifier and described switching tube couples, described switching tube is connected with described test port and described sampling resistor, and one end of described test port and described analog to digital converter couple.
2. Testing Instrument for Volt-ampere Characteristic as claimed in claim 1, is characterized in that, described switching tube is NMOS pipe or PMOS pipe.
3. Testing Instrument for Volt-ampere Characteristic as claimed in claim 2, it is characterized in that, described switching tube is NMOS pipe, the first end of described test port and default positive supply couple, the second end of described test port and second utmost point of described switching tube couple, first utmost point of described sampling resistor first end and described switching tube couples, described sampling resistor the second end ground connection, and the second end and the described analog to digital converter of described test port couple.
4. Testing Instrument for Volt-ampere Characteristic as claimed in claim 2, it is characterized in that, described switching tube is NMOS pipe, second utmost point of described switching tube and described default positive supply couple, first utmost point of described switching tube and the first end of described test port couple, the second end of the first end of described sampling resistor and described test port couples, the second end ground connection of described sampling resistor, and the first end of described test port and described analog to digital converter couple.
5. Testing Instrument for Volt-ampere Characteristic as claimed in claim 2, it is characterized in that, described switching tube is PMOS pipe, the first end of described sampling resistor and default positive supply couple, the second end of described sampling resistor and first utmost point of described switching tube couple, second utmost point of described test port first end and described switching tube couples, the second end ground connection of described test port, and the first end of described test port and described analog to digital converter couple.
6. Testing Instrument for Volt-ampere Characteristic as claimed in claim 2, it is characterized in that, described switching tube is PMOS pipe, the first end of described sampling resistor and default positive supply couple, the second end of described sampling resistor and the first end of described test port couple, first utmost point of described switching tube and the second end of described test port couple, the second utmost point ground connection of described switching tube, and the second end and the described analog to digital converter of described test port couple.
7. Testing Instrument for Volt-ampere Characteristic as claimed in claim 1, is characterized in that, also comprises: the storer coupling with described controller.
8. Testing Instrument for Volt-ampere Characteristic as claimed in claim 7, is characterized in that, described storer comprises following one: SD card, hard disk, EERROM, NOR Flash or Nand Flash.
9. Testing Instrument for Volt-ampere Characteristic as claimed in claim 1, is characterized in that, also comprises: the display coupling with described controller.
10. Testing Instrument for Volt-ampere Characteristic as claimed in claim 9, is characterized in that, described display comprises following one: LCD display or light-emitting diode display, OLED display or CRT monitor.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201320893243.3U CN203688696U (en) | 2013-12-31 | 2013-12-31 | Volt-ampere characteristic tester |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201320893243.3U CN203688696U (en) | 2013-12-31 | 2013-12-31 | Volt-ampere characteristic tester |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN203688696U true CN203688696U (en) | 2014-07-02 |
Family
ID=51010581
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201320893243.3U Expired - Lifetime CN203688696U (en) | 2013-12-31 | 2013-12-31 | Volt-ampere characteristic tester |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN203688696U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105093015A (en) * | 2015-07-28 | 2015-11-25 | 西安交通大学 | DC low-current volt-ampere characteristic double-electrode measurement method and device for carbon-fiber composite laminate |
-
2013
- 2013-12-31 CN CN201320893243.3U patent/CN203688696U/en not_active Expired - Lifetime
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105093015A (en) * | 2015-07-28 | 2015-11-25 | 西安交通大学 | DC low-current volt-ampere characteristic double-electrode measurement method and device for carbon-fiber composite laminate |
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|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CX01 | Expiry of patent term | ||
| CX01 | Expiry of patent term |
Granted publication date: 20140702 |