CN1595183A - Test circuit and test method thereof - Google Patents
Test circuit and test method thereof Download PDFInfo
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- CN1595183A CN1595183A CN 03156560 CN03156560A CN1595183A CN 1595183 A CN1595183 A CN 1595183A CN 03156560 CN03156560 CN 03156560 CN 03156560 A CN03156560 A CN 03156560A CN 1595183 A CN1595183 A CN 1595183A
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Abstract
This invention discloses a measurement circuit and its method. The said measurement circuit comprises the following: a series circuit with at least two switches series; a parallel circuit with at least groups of the said series circuit; a test module connected with the parallel circuit; the electron elements to be measured with one end connected between the random two said switches of the series circuit and with the end connected between the random said switches of the said series circuit. The said measurement method is to control the working status of each switch in the two groups of series circuit, which is connected with electron elements to be measured.
Description
Technical field
The present invention relates to the measuring technology of the communications field, particularly a kind of test circuit and based on the method for testing of this test circuit.
Background technology
At present, in order to grasp the internal work state of electronic equipment, need test some electronic component of its internal circuit usually.For example the backboard of communication facilities is tested, usually adopt special-purpose back plate testing equipment, because it is many that the backboard on the communication facilities has a network number of connection, characteristics such as the number of electronic components that need test is many are so need test the electronic component of inside by a plurality of test channel usually.Special-purpose back plate testing equipment generally need be realized a plurality of test channel are switched and choose by large-scale switching array.In existing special-purpose back plate testing equipment, generally adopt a plurality of contact relays arranged side by side to make switching array, any two contact relays just can be formed a test channel.
With reference to Fig. 1, be in special-purpose at present back plate testing equipment, adopt the contact relay to make the circuit diagram of switching array, include a plurality of contact relay r arranged side by side in the switching array 1
1, r
2, r
3... r
n, the disconnection of each contact relay and closed duty are controlled by decoding control circuit, and decoding control circuit carries out centralized control by CPU; One end of each contact relay is connected to the measured electronic elements on the backboard, and the other end is connected to test module.As working as two contact relay r in the switching array 1
1, r
2An end when being connected respectively to the two ends of a testing resistance 3, by the control of decoding control circuit, make to be input to this two contact relay r
1, r
2Control signal be high level, these two contact relay r then
1, r
2Can enter into closed duty; Then two ends are connected respectively to this two contact relay r
1, r
2The test module of the other end then can test out the resistance value of testing resistance 3 by the series loop of this formation.But being the true resistive value of testing resistance 3, the actual resistance that tests out adds two contact relay r
1, r
2Internal resistance sum own, test module is uploaded to CPU with the actual resistance that tests out and handles then.Although under the bigger situation of some measured electronic elements resistance value ratio, relay 2 internal resistances in contact own can be ignored, and under the measured electronic elements resistance is not very big situation, then may cause the measurement result out of true.
In addition, in the ordinary course of things, the electronic component of several ten thousand needs test is arranged all on the backboard, then also correspondingly need several ten thousand test channel, so just need make up and make switching array 1 with several ten thousand contact relays.The volume of each contact relay is very big and cost is higher, thereby handle is by a plurality of contact relay r
1, r
2, r
3... r
nThe switching array 1 that is combined into is applied in the special-purpose back plate testing equipment, switches the device of selection as a plurality of test channel, then can cause shortcomings such as special-purpose back plate testing equipment volume is big, cost cost height.
Summary of the invention
The present invention proposes a kind of test circuit and method of testing thereof, to solve test out of true and the high problem of test circuit cost that exists in the prior art.
For this reason, the present invention proposes a kind of test circuit, and described test circuit is composed as follows:
The string road that is composed in series by at least two switches;
By the described string of at least two groups road compose in parallel and the road;
With test module described and that the road is in parallel;
One is connected between any two described switches on one group of described string road, and the other end is connected to the measured electronic elements between another any two described switches of organizing described string road.
Wherein each switch of connecting in every group of described string road all is connected to decoding control circuit, is controlled the closed and disconnected duty of each switch by decoding control circuit.
Simultaneously according to above-mentioned test circuit, the present invention also proposes a kind of method of testing, measured electronic elements one is connected to the A point between any two switches on one group of described string road, simultaneously the other end is connected to the B point between another any two switches of organizing described string road; Test module one is connected to the side C point on described and road, simultaneously the other end is connected to the opposite side D point on described and road, described method of testing comprises the steps:
(1) with the switch closure between AC section and the AD section, simultaneously the switch between BC section and the BD section is disconnected, test obtaining test value S1 by test module;
(2) switch between AC section and the AD section is disconnected,, test to obtain test value S2 by test module simultaneously with the switch closure between BC section and the BD section;
(3) with the switch closure between AC section and the BD section, simultaneously the switch between BC section and the AD section is disconnected, test obtaining test value S3 by test module;
(4) switch between AC section and the BD section is disconnected,, test to obtain test value S4 by test module simultaneously with the switch closure between BC section and the AD section;
(5), obtain the test result of measured electronic elements according to described test value S1, S2, S3, S4.
The test result of measured electronic elements is obtained by following formula in the described step (5): test result=(S4+S3-S2-S1)/2.
Wherein the closed and disconnection duty of each switch in each switch segments is imported control by decoding control circuit.
Beneficial effect of the present invention: because test circuit of the present invention adopts switch combination to make switching array, volume is little, the cost low cost and other advantages thereby the testing apparatus that makes employing test circuit of the present invention make has.Owing to adopt the method for testing of the present invention's proposition, can consider the influence of switch internal resistance, thereby improve the degree of accuracy of test result simultaneously test result.
Description of drawings
Fig. 1 is the circuit diagram that a plurality of contacts of available technology adopting relay is made a switching array;
Fig. 2 is after test circuit of the present invention adopts two switch series joint group bunchiness roads, forms the circuit diagram of a switching array;
Fig. 3 is the simplified electrical circuit diagram of Fig. 2 circuit;
Fig. 4 is after test circuit of the present invention adopts three switch series joint group bunchiness roads, forms the circuit diagram of a switching array;
Fig. 5 is the simplified electrical circuit diagram of Fig. 4 circuit;
Fig. 6 is that test circuit of the present invention adopts a plurality of Fig. 3 circuit series connection, to be used for the simplified electrical circuit diagram that a plurality of test modules are tested simultaneously.
Embodiment
With reference to Fig. 2, be after test circuit of the present invention adopts two switch series joint group bunchiness roads, form the circuit diagram of a switching array.
At first by at least two switch series joint group bunchiness roads; As forming one group of string road by K switch 1, K2 respectively, K switch 3, K4 form one group of string road, K switch 5, K6 and form one group of string road, K switch 7, K8 and form one group of string road, and subsequent can also have so many groups string road, is the example explanation with these four groups of string roads only here.
Composed in parallel and the road by the described string of at least two groups road then, the string road as will be above-mentioned many groups is in parallel to form an also road.
It is in parallel that test module and described and road are carried out, and is about to a side on the above-mentioned and road of test module one termination, and the other end connects the opposite side on above-mentioned and road, is about to the both sides that test module is connected in parallel on this and road, makes test module also form relation in parallel with road also.
Measured electronic elements one is connected between any two described switches on one group of described string road, the other end is connected between another any two described switches of organizing described string road, go here and there between the K switch 1, K2 on road as testing resistance R one being connected to form by K switch 1, K2, the testing resistance R other end is connected to be made up of K switch 3, K4 goes here and there between the K switch 3, K4 on road, the annexation on other measured electronic elements and above-mentioned and road, identical with the annexation on above-mentioned testing resistance R and above-mentioned and road, repeat no more here.
By above-mentioned annexation, can form the circuit diagram of the switching array that adopts two switch series joint group bunchiness roads.All switches in the switching array of this formation all are connected to decoding control circuit, by decoding control circuit each switch is imported control, the input end incoming level of controlling certain switch as decoding control circuit is for high, can make the switch closure of its control, when this input end incoming level is low, the switch of its control is disconnected.The selection of each input end incoming level height of decoding control circuit is set by carrying out mcu programming in advance, and by the unified control of CPU.
With reference to Fig. 3, be the simplification switching array figure that is connected with two groups of string roads compositions of testing resistance R in Fig. 2 switching array.The string road parallel connection that string road that K switch 1, K2 form and K switch 3, K4 form, testing resistance R one is connected between K switch 1, the K2, the other end is connected between K switch 3, the K4, test module is formed with above-mentioned K switch 1, K2, K3, K4 and road is carried out in parallel once more, the resistance that is used to test testing resistance R; Closed and the disconnection duty of wherein above-mentioned K switch 1, K2, K3, K4 is imported control by decoding control circuit.The circuit that above-mentioned in fact K switch 1, K2, K3, K4 and testing resistance R are formed is bridge circuit, makes up the resistance of testing testing resistance R by K switch 1, K2, K3, duty that K4 is different.
With reference to Fig. 4, be after test circuit of the present invention adopts three switch series joint group bunchiness roads, form the circuit diagram of a switching array; Here every group of string road is composed in series by 3 switches, to organize the string road that is composed in series by 3 switches more then and carry out the switching array of making in parallel one by one, other catenation principles of this switching array are with after adopting two switch series joint group bunchiness roads among Fig. 2, the principle that forms a switching array is identical, is not giving unnecessary details here.
With reference to Fig. 5, be the simplification switching array figure that is connected with two groups of string roads compositions of testing resistance R in Fig. 4 switching array.The string road parallel connection that string road that K switch 1, K2, K3 form and K switch 7, K8, K9 form, testing resistance R one is connected between K switch 1, the K2, the other end is connected between K switch 8, the K9, test module is formed with above-mentioned K switch 1, K2, K3, K7, K8, K9 and road is carried out in parallel once more, the resistance that is used to test testing resistance R; Closed and the disconnection duty of wherein above-mentioned K switch 1, K2, K3, K7, K8, K9 is imported control by decoding control circuit.Above-mentioned in fact K switch 1, K2, K3, K7, K8, the circuit that K9 and testing resistance R formed also are bridge circuit, make up the resistance of testing testing resistance R by K switch 1, K2, K3, K7, K8, duty that K9 is different.
With reference to Fig. 6, be that test circuit of the present invention adopts N Fig. 3 circuit series connection, to be used for the simplified electrical circuit diagram that N test module tested simultaneously.N bridge circuit shown in Figure 3 connected one by one, form N switching array, simultaneously N measured electronic elements tested to be used for N test module, N described here is the natural number more than or equal to 2.
To sum up, in the testing apparatus that adopts test circuit of the present invention, every group of string road can take a plurality of switches to connect, the string road that many groups are composed in series by a plurality of switches is carried out parallel connection again and is made each switching array, a plurality of switching arrays can also be connected simultaneously, a plurality of measured electronic elements be tested simultaneously to be used for a plurality of test modules.Every group of tandem tap quantity that the string road is selected in each switching array, and each switching array carries out parallel connection by how many group string roads, and specifically by what switching arrays connect and test simultaneously to be used for a plurality of test modules, the quantity size of the measured electronic elements that these parameters all specifically need be tested by the testing apparatus that adopts test circuit of the present invention is determined.
Applied all switches can adopt analog switch in the test circuit of the present invention, because analog switch corresponds to the cost performance of other switches than higher.But analog switch has internal resistance, when using analog switch, just must deduct the internal resistance value of analog switch in the end value that records.But in practice, the internal resistance value of each analog switch has nothing in common with each other, even to same analog switch, is operated under the different current conditions, and its internal resistance value also is inconsistent.
The method of testing that the present invention proposes can be considered the influence of switch internal resistance to test result, makes test result more accurate.With reference to Fig. 3, be that example illustrates concrete method of testing with the resistance of test testing resistance R, measured electronic elements one is connected to the A point between any two switches on one group of described string road, in Fig. 3, A point is located between the K switch 1 of going here and there in the road, the K2;
Simultaneously the measured electronic elements other end is connected to the B point between another any two switches of organizing described string road, in Fig. 3, the B point is between the K switch 3 of another string in road, K4;
Test module one is connected to the side C point on described and road, simultaneously the other end is connected to the opposite side D point on described and road; As shown in Figure 3, the C point is the point that test module one end is connected with K switch 1, K3 simultaneously, and the D point is the point that the test module other end is connected with K switch 2, K4 simultaneously.The process of test testing resistance R is:
With the whole switch closures between AC section and the AD section, simultaneously the whole switches between BC section and the BD section are disconnected, test obtaining test value S1 by test module; In Fig. 3, be about to the input end input high level of the decoding control circuit of gauge tap K1, K2, make K switch 1, K2 closure, simultaneously with the input end input low level of the decoding control circuit of gauge tap K3, K4, K switch 3, K4 are disconnected, thereby make K switch 1, K2 and test module constitute a loop, test module records test value R1=R
K1+ R
K2
Whole switches between AC section and the AD section are disconnected,, test to obtain test value S2 by test module simultaneously with the whole switch closures between BC section and the BD section; In Fig. 3, be about to the input end input low level of the decoding control circuit of gauge tap K1, K2, K switch 1, K2 are disconnected, simultaneously with the input end input high level of the decoding control circuit of gauge tap K3, K4, make K switch 3, K4 closure, thereby make K switch 3, K4 and test module constitute a loop, test module records test value R2=R
K3+ R
K4
With the whole switch closures between AC section and the BD section, simultaneously the whole switches between BC section and the AD section are disconnected, test obtaining test value S3 by test module; In Fig. 3, be about to the input end input high level of the decoding control circuit of gauge tap K1, K4, make K switch 1, K4 closure, simultaneously with the input end input low level of the decoding control circuit of gauge tap K2, K3, K switch 2, K3 are disconnected, thereby make K switch 1, R, K4 and test module constitute a loop, test module records test value R3=R
K1+ R+R
K4
Whole switches between AC section and the BD section are disconnected,, test to obtain test value S4 by test module simultaneously with the whole switch closures between BC section and the AD section; In Fig. 3, be about to the input end input low level of the decoding control circuit of gauge tap K1, K4, K switch 1, K4 are disconnected, simultaneously with the input end input high level of the decoding control circuit of gauge tap K2, K3, make K switch 2, K3 closure, thereby make K switch 2, R, K3 and test module constitute a loop, test module records test value R4=R
K2+ R+R
K3
Thereby can obtain measured electronic elements test result=(S4+S3-S2-S1)/2, wherein S is the symbol table indicating value of broad sense, with the difference of measured electronic elements, this symbol S can change thereupon.When being resistance as measured electronic elements, the S symbol can replace with the R symbol; When and for example measured electronic elements was voltage, the S symbol can replace with the U symbol.Measured electronic elements is a resistance herein, so replace symbol S with symbol R.In Fig. 3, further calculate the true resistive value of testing resistance R by the above-mentioned R1 that tries to achieve, R2, R3 and R4, then the true resistive value of testing resistance R=(R4+R3-R2-R1)/2=[(R
K2+ R+R
K3)+(R
K1+ R+R
K4)-(R
K1+ R
K2)-(R
K3+ R
K4)]/2=R, so, in test process, can consider the influence of switch internal resistance, make test result more accurate to test result by above-mentioned method of testing.
For the situation by 3 switch series joint group bunchiness roads shown in Figure 5, its method of testing is similar with the test process of Fig. 3.At first make K switch 1, K2, K3 closure, K switch 7, K8, K9 are disconnected obtain a test value R1=R
K1+ R
K2+ R
K3K switch 1, K2, K3 are disconnected, make K switch 7, K8, K9 closure obtain a test value R2=R simultaneously
K7+ R
K8+ R
K9Make K switch 1, K9 closure again, K switch 2, K3, K7 and K8 are disconnected obtain a test value R3=R
K1+ R+R
K9K switch 1, K9 are disconnected, make K switch 2, K3, K7 and K8 closure obtain a test value R4=R simultaneously
K2+ R
K3+ R+R
K7+ R
K8Obtain the true resistance value of testing resistance R=(R4+R3-R2-R1)/2=[(R
K2+ R
K3+ R+R
K7+ R
K8)+(R
K1+ R+R
K9)-(R
K7+ R
K8+ R
K9)-(R
K1+ R
K2+ R
K3)]/2=R.
The prerequisite that above-mentioned method of testing realizes is that the resistance of measured electronic elements is constant all the time in the whole process of test, supposes that itself attribute can not follow the variation of test voltage or measuring current and change.In fact generally speaking, as the internal resistance of analog switch all between 75～130 ohm, when measured electronic elements when 2K ohm is following, the variable quantity of analog switch internal resistance is negligible.And when measured electronic elements when 2K ohm is above, the internal resistance of analog switch is just very little to the influence of test result, himself internal resistance is negligible.
Test circuit of the present invention and method of testing thereof not only can be applied to the electronic component on the testing backboard, can also be used for excitation and measure other electric current and voltage numerical value.
The above only is a preferred implementation of the present invention; should be pointed out that for those skilled in the art, under the prerequisite that does not break away from the principle of the invention; can also make some improvements and modifications, these improvements and modifications also should be considered as protection scope of the present invention.
Claims (6)
1, a kind of test circuit is characterized in that, described test circuit comprises: the string road that is composed in series by at least two switches; By the described string of at least two groups road compose in parallel and the road; With test module described and that the road is in parallel;
One is connected between any two described switches on one group of described string road, and the other end is connected to the measured electronic elements between another any two described switches of organizing described string road.
2, test circuit according to claim 1 is characterized in that, each switch of connecting in every group of described string road all is connected to decoding control circuit, is controlled the closed and disconnected duty of each switch by decoding control circuit.
3, test circuit according to claim 1 and 2 is characterized in that, described switch is an analog switch.
4, a kind of method of testing of the test circuit based on claim 1 is connected to measured electronic elements one the A point between any two switches on one group of described string road, simultaneously the other end is connected to the B point between another any two switches of organizing described string road; Test module one is connected to the side C point on described and road, simultaneously the other end is connected to the opposite side D point on described and road, it is characterized in that described method of testing comprises the steps:
(1) with the switch closure between AC section and the AD section, simultaneously the switch between BC section and the BD section is disconnected, test obtaining test value S1 by test module;
(2) switch between AC section and the AD section is disconnected,, test to obtain test value S2 by test module simultaneously with the switch closure between BC section and the BD section;
(3) with the switch closure between AC section and the BD section, simultaneously the switch between BC section and the AD section is disconnected, test obtaining test value S3 by test module;
(4) switch between AC section and the BD section is disconnected,, test to obtain test value S4 by test module simultaneously with the switch closure between BC section and the AD section;
(5), obtain the test result of measured electronic elements according to described test value S1, S2, S3 and S4.
5, method of testing according to claim 4 is characterized in that, the test result of measured electronic elements is obtained by following formula in the described step (5):
Test result=(S4+S3-S2-S1)/2.
6, method of testing according to claim 4 is characterized in that, the closed and disconnection duty of each switch in each switch segments is imported control by decoding control circuit.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB031565603A CN100354637C (en) | 2003-09-09 | 2003-09-09 | Test circuit and test method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB031565603A CN100354637C (en) | 2003-09-09 | 2003-09-09 | Test circuit and test method thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1595183A true CN1595183A (en) | 2005-03-16 |
| CN100354637C CN100354637C (en) | 2007-12-12 |
Family
ID=34660021
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNB031565603A Expired - Fee Related CN100354637C (en) | 2003-09-09 | 2003-09-09 | Test circuit and test method thereof |
Country Status (1)
| Country | Link |
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| CN (1) | CN100354637C (en) |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100476394C (en) * | 2005-12-31 | 2009-04-08 | 华为技术有限公司 | Detecting system and method |
| CN102375099A (en) * | 2010-08-16 | 2012-03-14 | 深圳富泰宏精密工业有限公司 | Portable-type electronic device testing system |
| CN102854386A (en) * | 2012-08-02 | 2013-01-02 | 深圳市明微电子股份有限公司 | Resistance test method |
| CN103364702A (en) * | 2012-04-02 | 2013-10-23 | 威光自动化科技股份有限公司 | Test system |
| CN106128344A (en) * | 2016-08-17 | 2016-11-16 | 深圳晶华显示器材有限公司 | A kind of generic disk being applied to LCD product test |
| CN109342574A (en) * | 2018-12-03 | 2019-02-15 | 中国海洋大学 | A kind of sound emission multichannel fast switching system and switching method |
| CN113933684A (en) * | 2021-09-26 | 2022-01-14 | 武汉光谷信息光电子创新中心有限公司 | System and method for testing chip characteristics |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE2630993C3 (en) * | 1976-07-09 | 1979-12-06 | Siemens Ag, 1000 Berlin Und 8000 Muenchen | Switching matrix with connection modules |
| FR2365804A1 (en) * | 1976-09-23 | 1978-04-21 | Gris Marcel | LUMINESCENT TUBE VOLTAGE INDICATOR WITH BUILT-IN CONTROL CIRCUIT |
| JPS58178268A (en) * | 1982-04-12 | 1983-10-19 | Meidensha Electric Mfg Co Ltd | Test circuit |
| WO1999042850A1 (en) * | 1998-02-18 | 1999-08-26 | Luther & Maelzer Gmbh | Method and device for testing printed circuit boards |
| CN1152471C (en) * | 2000-01-17 | 2004-06-02 | 华为技术有限公司 | D/A converter with current helm structure for 12C logic |
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2003
- 2003-09-09 CN CNB031565603A patent/CN100354637C/en not_active Expired - Fee Related
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100476394C (en) * | 2005-12-31 | 2009-04-08 | 华为技术有限公司 | Detecting system and method |
| CN102375099A (en) * | 2010-08-16 | 2012-03-14 | 深圳富泰宏精密工业有限公司 | Portable-type electronic device testing system |
| CN103364702A (en) * | 2012-04-02 | 2013-10-23 | 威光自动化科技股份有限公司 | Test system |
| CN102854386A (en) * | 2012-08-02 | 2013-01-02 | 深圳市明微电子股份有限公司 | Resistance test method |
| CN102854386B (en) * | 2012-08-02 | 2015-08-05 | 深圳市明微电子股份有限公司 | A kind of method for testing resistance |
| CN106128344A (en) * | 2016-08-17 | 2016-11-16 | 深圳晶华显示器材有限公司 | A kind of generic disk being applied to LCD product test |
| CN109342574A (en) * | 2018-12-03 | 2019-02-15 | 中国海洋大学 | A kind of sound emission multichannel fast switching system and switching method |
| CN109342574B (en) * | 2018-12-03 | 2024-02-06 | 中国海洋大学 | Acoustic emission multichannel rapid switching system and switching method |
| CN113933684A (en) * | 2021-09-26 | 2022-01-14 | 武汉光谷信息光电子创新中心有限公司 | System and method for testing chip characteristics |
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|---|---|
| CN100354637C (en) | 2007-12-12 |
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