CN101145805B - A testing device and method for up-pull resistance input signal cable - Google Patents
A testing device and method for up-pull resistance input signal cable Download PDFInfo
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- CN101145805B CN101145805B CN2007100743979A CN200710074397A CN101145805B CN 101145805 B CN101145805 B CN 101145805B CN 2007100743979 A CN2007100743979 A CN 2007100743979A CN 200710074397 A CN200710074397 A CN 200710074397A CN 101145805 B CN101145805 B CN 101145805B
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Abstract
The invention relates to a test device and a method of an input signal wire with a pull-up resistor. The device comprises a switch, and a high level resistor R1 and a low level resistor R2 with one earthed end respectively. The R1 and the R2 are respectively connected with the pull-up resistor in series between the power of a tested unit and the earth through switching to set the high level preset value and the low level preset value of the tested input signal wire. In test, the tested input signal wire is connected with the high level resistor and the low level resistor successively, and the first level value and the second level value of the tested input signal are read out; the input signal wire is judged whether normal or not according to the first level value and the second level value. When the first level value and the second level value are respectively equal to the high level set value and the low level set value, the tested input signal wire as well as the pull-up resistor thereof is normal; or, the input signal wire or the pull-up resistor is broken down. The method can test the state of the input signal wire, and can judge the state of the pull-up resistor thereof as well.
Description
Technical field
The present invention relates to detection field in electronics and the communication system, relate in particular to a kind of detection with testing apparatus and the method for testing of pull-up resistor input signal cable.
Background technology
Along with developing rapidly of electronics and mechanics of communication, so that electronic equipment becomes increasingly complex, integrated level is also more and more higher.In order to make in the equipment circuit on the circuit board and the circuit between circuit board can co-ordination, a large amount of input on the circuit board, the introducing of output signal line be absolutely necessary.
Yet in process of production, perhaps in the use procedure, the part input on the circuit board, output signal line may cause damage.For input signal cable, often can produce following fault:
1. input signal cable is fixed and pulls into high level.Namely this input signal cable can only receive 1, and when sending 0 toward this input signal cable, data can't be correctly received;
2. input signal cable is fixed and pulls into low level.Namely this input signal cable can only receive 0, and when sending 1 toward this input signal cable, data can't be correctly received;
3. adjacent input wire size line is short-circuited.Namely physically the adjacent input wire size line more than two or two sticks together, and these input signal cables can only receive identical data.
Usually in order to make input wire size line when not having external data, it can keep high level, also connects pull-up resistor at input wire size line.This can have a kind of Validity Test apparatus and method to testing with the input signal cable of pull-up resistor with regard to needing, and finds out rapidly bad holding wire with the convenient for maintaining personnel, the location failure cause.At present, usually to the testing equipment structure of testing with pull-up resistor input wire size line as shown in Figure 1, method of testing is: the IO resource card that utilizes various test platforms to provide, by certain switching device, tested input wire size line each IO signal with the IO resource card is docked one by one, if the level character of the level character of IO resource card and detected input signals line is inconsistent, in switching device, also need to add the signal level conversion circuit.The signal condition of IO resource card output appointment is to the detected input signals line, by the CPU of tested input wire size line place system read the input signal line states whether with the specification signal state consistency of IO resource card output, judge by this method whether input signal cable normal.
This method of testing need to be introduced the IO resource card, and when input signal cable during with pull-up resistor, pull-up resistor has problem, if the pull-up resistor open circuit, tested input signal cable is no problem, can't find the pull-up resistor open circuit through this method of testing; If pull-up resistor is owing to identical resistance or the short circuit of pull-up resistor place that is welded into zero ohm of encapsulation, the detected input signals line is directly connected on the power supply, when at this time if the IO of the IO resource card that provides of test platform exports to tested input wire size line and is low level, the VDD-to-VSS short-circuit conditions be will cause, IO resource card or detected input signals line place circuit board easily burnt.And if the method for testing that adopts is improper, can't test out adjacent signals line short-circuit conditions.
Therefore, there is defective in prior art, needs to improve.
Summary of the invention
The object of the invention is to solve problems of the prior art, provide a kind of testing apparatus with the pull-up resistor input signal cable and to the method for testing of input signal cable, adopt the method for testing of this device not only can effectively test out the quality of input signal cable, and whether have fault also can judge to the pull-up resistor of detected input signals line.
For achieving the above object, the invention provides a kind of testing apparatus with the pull-up resistor input signal cable, described testing apparatus comprises with each with the detected input signals line of pull-up resistor R test cell one to one, wherein, each test cell comprises: high level resistance R 1 and the low-level resistance R2 of a switch, two end ground connection, the stiff end of described switch connects the detected input signals line, the first selecting side of described switch be connected the selecting side and connect respectively the other end of high level resistance R 1 and low-level resistance R2, the other end of pull-up resistor R connects power supply VCC; And when the setting of described high level resistance R 1 and low-level resistance R2 resistance makes described switch throw to the first selecting side, the level value that the detected input signals line reads is high level, pull-up resistor R and high level resistance R 1 are serially connected between power supply VCC and the ground, when described switch is thrown to the second selecting side, the level value that the detected input signals line reads is low level, and pull-up resistor R and low-level resistance R2 are serially connected between power supply VCC and the ground;
Wherein, when testing many detected input signals lines simultaneously, access incompatible level at the adjacent input signal cable of synchronization.
Described testing apparatus, wherein: following formula: R1 * VCC/ (R+R1)＞V is satisfied in arranging of described high level resistance R 1 and low-level resistance R2 resistance
Hmin, R2 * VCC/ (R+R2)＜V
Lmax,
Wherein: VCC is the unit under test power supply, and R is the pull-up resistor of detected input signals line, V
HminBe the high level minimum threshold of unit under test, V
LmaxLow level maximum threshold for unit under test.
Described testing apparatus, wherein: described switch is the hilted broadsword bidirectional switch.
Adopt the as above method of testing apparatus to testing with the pull-up resistor input signal cable, may further comprise the steps: A, by respectively high level resistance and low-level resistance and pull-up resistor being serially connected between unit under test power supply and the ground, the stiff end of switch connects the detected input signals line, the first selecting side be connected the selecting side and connect respectively high level and the low level other end, high level set point and low level set point that the detected input signals line should read are set;
B, by switching over, successively the detected input signals line is connected with low-level resistance with high level resistance, read respectively the first level value and the second electrical level value of detected input signals line;
C, judge according to the first level value and second electrical level value whether input signal cable is normal, when the first level value equals the high level set point, and when the second electrical level value equals the low level set point, determine this detected input signals line with and pull-up resistor normal, otherwise, determine that this detected input signals line or its pull-up resistor have fault;
Wherein, when testing many detected input signals lines simultaneously, access incompatible level at the adjacent input signal cable of synchronization, when the level value of adjacent two detected input signals lines is consistent, judge two detected input signals lines short circuit that this is adjacent.
Compared with prior art, a kind of testing apparatus and its method of testing with the pull-up resistor input signal cable provided by the invention is fit to single and many tests with the pull-up resistor input signal cable very much, can judge the quality of input signal cable, also can judge tested input wire size pull-up resistor that line is with and whether have fault; And during the pull-up resistor short circuit, test process can not cause short circuit between power supply and the ground, the circuit board at protection detected input signals line place; Adopt testing apparatus of the present invention and method of testing thereof can also test out the situation of short circuit between the adjacent detected input signals line.And testing apparatus simplicity of design of the present invention, cost are lower, convenient for maintaining personnel test failure.
Description of drawings
Fig. 1 is existing testing equipment structural representation to input signal cable;
Fig. 2 is testing apparatus of the present invention, and adopts this device to single test structure schematic diagram with the pull-up resistor input signal cable;
Fig. 3 is that the present invention is to many test structure schematic diagrames with the pull-up resistor input signal cable.
Embodiment
Below in conjunction with accompanying drawing, preferred embodiment of the present invention is described in further detail.
Testing apparatus of the present invention and to single test structure schematic diagram with the pull-up resistor input signal cable as shown in Figure 2: be connected with a pull-up resistor R on the input signal cable of unit under test, the other end of described pull-up resistor R connects unit under test power supply VCC, described input signal cable access test cell with pull-up resistor R; Described test cell comprises a K switch 1, the high level resistance R 1 of two end ground connection and low-level resistance R2, the stiff end 2 of described K switch 1 is connected on the detected input signals line, the first selecting side 1 of K switch 1 connects the other end of described high level resistance R 1, and the second selecting side 0 of K1 connects the other end of low-level resistance R2.When K switch 1 was thrown to high level resistance R 1, pull-up resistor R and high level resistance R 1 were serially connected between power supply VCC and the ground like this, and when K switch 1 was thrown to low-level resistance R2, pull-up resistor R and low-level resistance R2 were serially connected between power supply VCC and the ground.When the setting of high level resistance R 1 and low-level resistance R2 resistance should make K switch 1 throw to 1 end, the level value that described detected input signals line reads was high level; When described K switch 1 was thrown to the other end 0 end, the level value that described detected input signals line reads was low level.For this reason, resistance R 1, R2 resistance are chosen and should be satisfied following formula:
R1×VCC/(R+R1)＞V
Hmin (1)
R2×VCC/(R+R2)＜V
Lmax (2)
Wherein VCC is the power supply of unit under test, and R is the pull-up resistor of detected input signals line, V
HminBe the high level minimum threshold of unit under test place system, V
LmaxLow level maximum threshold for unit under test place system.For example unit under test is the COMS circuit of 3.3V, i.e. VCC=3.3V, wherein V
Hmin=0.8VCC=2.64V, V
Lmax=0.2Vcc=0.66V.
Choosing according to the resistance of described pull-up resistor R size and formula (1) and (2) of the R2 resistance of described high level resistance R 1 and low-level resistance is definite.
For example work as VCC=3.3V, V
Hmin=2.64V, V
Lmax=0.66V, R=10K,
By inequality R 1 * VCC/ (R+R1)＞V
Hmin, calculate R1＞4R=40K;
By inequality R 2 * VCC/ (R+R2)＜V
Lmax, calculate R2＜R/4=2.5K.
After R1 and R2 determine, the level that reads on the holding wire when R1 is accessed the detected input signals line is the high level set point, and the level that reads on the holding wire when R2 accessed the detected input signals line is the low level set point, for example choose R1=50K, R2=10K is when detected input signals line and pull-up resistor all under the normal state, when K switch 1 connects to 1 end, the high level set point that reads is 2.75V, and when K switch 1 connect to 0 end, the low level set point that reads was 0.55V.
The described K switch 1 that the present invention adopts is the hilted broadsword two-way type, also can adopt the switch of other formal construction, can play the above function and get final product, and the present invention is also unrestricted to this.
In conjunction with above contrive equipment, inventive principle and Fig. 2, the below introduces method of testing.Actual test is divided into two steps:
The first step, described hilted broadsword bidirectional switch K1 is thrown to the selecting side 1, by K switch 1, make high level resistance R 1 connect the detected input signals line, the detected input signals line should read in high level, and the level value that this moment, unit under test read on the input signal cable is the first level value;
Second step throws to the selecting side 0 with described hilted broadsword bidirectional switch K1, makes low-level resistance R2 connect the detected input signals line, and the detected input signals line should read in low level, and the level value that this moment, unit under test read on the input signal cable is the second electrical level value.
Through above-mentioned two pacings examination, only have the first level value and the second electrical level value of reading when unit under test, consistent with high level set point and low level set point respectively, then all successes of two pacings examination illustrate that detected input signals line and its pull-up resistor are all normal; Otherwise described input signal cable or pull-up resistor R have fault.If pull-up resistor R is intact, in the out of order situation of input signal cable, through above-mentioned two testing procedures, actual the first level value read of unit under test and second electrical level value are inconsistent with high level set point and low level set point respectively, and can locate the detected input signals line has fault.If the detected input signals line is intact, pull-up resistor R is owing to the identical resistance that is welded into zero ohm of encapsulation, or in the situation of pull-up resistor R place's short circuit, and then the first level value and the second electrical level value that go out of two pacing academic probations all is high level; If pull-up resistor R open circuit, then the first level value and the second electrical level value that go out of two pacing academic probations all is low level, so just tests out the fault of described pull-up resistor R.
This shows, adopt the method for testing of testing apparatus of the present invention not only can effectively test out the quality of input signal cable, and whether have fault also can judge to pull-up resistor.And in the situation that pull-up resistor R short circuit; in test process since test cell in resistance R 1 or R2 be serially connected between power supply VCC and the ground; can not cause power supply VCC with the short circuit between the ground, protect the circuit board at detected input signals line place can not burnt because of its power supply short circuit.
For many tests with the pull-up resistor input signal cable, testing apparatus and method that every holding wire is wherein tested are consistent with single input signal cable with pull-up resistor.If the detected input signals line is one group of holding wire at circuit board, its physics cabling is adjacent, the situation that adjacent detected input signals line is short-circuited at this moment may occur.When physically adjacent band pull-up resistor input signal cable is tested to many at the same time, in order to test between the adjacent input signal cable whether short circuit, can not make the adjacent signals line access simultaneously the level value of same nature at synchronization, control described hilted broadsword bidirectional switch K, make adjacent input signal cable access incompatible level at synchronization, namely a detected input signals line accesses high value, then another one detected input signals line access low level value; Otherwise the situation that the adjacent signals line is short-circuited just can't test out.
As shown in Figure 3, take three unit under tests with pull-up resistor as example, three velamens are surveyed input signal cable a, b, c physically are arranged in order according to adjacent order, and every velamen is surveyed the corresponding testing apparatus of input signal cable.Be divided into for two steps in the time of test:
The first step throws the K switch 1 that detected input signals line a connects to the selecting side 1 that connects high level resistance R a1; The K switch 2 that detected input signals line b connects is thrown to the selecting side 0 that connects low-level resistance Rb2; The K switch 3 that detected input signals line c connects is thrown to the selecting side 1 that connects high level resistance R a3.This moment, detected input signals line a should read in that high level, detected input signals line b should read in low level, detected input signals line c should read in high level, and the first level value that unit under test a reads should be consistent with this unit high level set point, the first level value that unit under test b reads should be consistent with this unit low level set point, and the first level value that unit under test c reads should be consistent with this unit high level set point;
Second step, described hilted broadsword bidirectional switch K1, K2 and K3 are received its another one selecting side opposite with the first step, this moment, detected input signals line a should read in that low level, detected input signals line b should be read in high level, detected input signals line c should read in low level, and the second electrical level value that unit under test a reads should be consistent with this unit low level set point, the second electrical level value that unit under test b reads should be consistent with this unit high level set point, and the second electrical level value that unit under test c reads should be consistent with this unit low level set point
Through all successes of as above two pacings examination, then test is passed through, and illustrate that three detected input signals line a, b, c and its pull-up resistor Ra, Rb, Rc are normal, otherwise assert that detected input signals line or its pull-up resistor have the fault existence.For the detected input signals line that has fault to exist, can according to the criterion location input signal cable of the single input signal cable of pull-up resistor and with the fault of pull-up resistor.
If described adjacent two detected input signals line a, b, simultaneously test obtains the level value that two unit under tests read always consistent, is a certain determined value, can judge short circuit between described two adjacent input signal cable a, b.
In a word, the present invention is not limited to above-mentioned execution mode, anyly is familiar with this operator, without departing from the spirit and scope of the present invention, all should drop within protection scope of the present invention.
Claims (4)
1. testing apparatus with the pull-up resistor input signal cable, it is characterized in that: comprise with each with the detected input signals line of pull-up resistor R test cell one to one, wherein, each test cell comprises: high level resistance R 1 and the low-level resistance R2 of a switch, two end ground connection, the stiff end of described switch connects the detected input signals line, the first selecting side of described switch be connected the selecting side and connect respectively the other end of high level resistance R 1 and low-level resistance R2, the other end of pull-up resistor R connects power supply VCC; And when the setting of described high level resistance R 1 and low-level resistance R2 resistance makes described switch throw to the first selecting side, the level value that the detected input signals line reads is high level, pull-up resistor R and high level resistance R 1 are serially connected between power supply VCC and the ground, when described switch is thrown to the second selecting side, the level value that the detected input signals line reads is low level, and pull-up resistor R and low-level resistance R2 are serially connected between power supply VCC and the ground;
Wherein, when testing many detected input signals lines simultaneously, access incompatible level at the adjacent input signal cable of synchronization.
2. device according to claim 1 is characterized in that: following formula is satisfied in arranging of described high level resistance R 1 and low-level resistance R2 resistance:
R1×VCC/(R+R1)＞V
Hmin，
R2×VCC/(R+R2)＜V
Lmax，
Wherein: VCC is the unit under test power supply, and R is the pull-up resistor of detected input signals line, V
HminBe the high level minimum threshold of unit under test, V
LmaxLow level maximum threshold for unit under test.
3. device according to claim 1 and 2, it is characterized in that: described switch is the hilted broadsword bidirectional switch.
4. method of testing with the pull-up resistor input signal cable, corresponding detected input signals line arranges a testing apparatus, and the method may further comprise the steps:
A, by respectively high level resistance and low-level resistance and pull-up resistor being serially connected between unit under test power supply and the ground, high level set point and low level set point that the detected input signals line should read are set;
B, priority are connected with high level resistance the detected input signals line with low-level resistance, the level value that reads respectively the detected input signals line is the first level value and second electrical level value;
C, judge according to the first level value and second electrical level value whether input signal cable is normal, when the first level value equals the high level set point, and when the second electrical level value equals the low level set point, determine this detected input signals line with and pull-up resistor normal, otherwise, determine that this detected input signals line or its pull-up resistor have fault;
Wherein, when testing many detected input signals lines simultaneously, access incompatible level at the adjacent input signal cable of synchronization, when the level value of adjacent two detected input signals lines is consistent, judge two detected input signals lines short circuit that this is adjacent.
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| Application Number | Priority Date | Filing Date | Title |
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| CN2007100743979A CN101145805B (en) | 2007-05-18 | 2007-05-18 | A testing device and method for up-pull resistance input signal cable |
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|---|---|---|---|
| CN2007100743979A CN101145805B (en) | 2007-05-18 | 2007-05-18 | A testing device and method for up-pull resistance input signal cable |
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| CN101145805B true CN101145805B (en) | 2013-01-09 |
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Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101493490B (en) * | 2009-02-23 | 2013-03-27 | 华为终端有限公司 | Terminal port insertion detection circuit |
| CN104217042B (en) * | 2013-05-30 | 2017-08-25 | 昆达电脑科技(昆山)有限公司 | The System and method for of the multiple pull-up resistor of automation inspection |
| CN105426557B (en) * | 2014-09-19 | 2018-11-06 | 昆达电脑科技(昆山)有限公司 | The system and method for automation inspection pull-up resistor |
| CN109901041A (en) * | 2017-12-07 | 2019-06-18 | 英业达科技有限公司 | The test macro and its method of differential clock signal |
| CN112578899B (en) * | 2020-12-10 | 2023-08-29 | 海光信息技术股份有限公司 | Asynchronous digital correction circuit, method, apparatus, and storage medium |
| CN114184936B (en) * | 2021-11-30 | 2023-06-27 | 上海儒竞智控技术有限公司 | Chip bonding self-detection method, system, medium and chip |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3940571A (en) * | 1974-11-04 | 1976-02-24 | Gte Sylvania Incorporated | Drive circuitry with error detection |
| CN1336659A (en) * | 2000-05-17 | 2002-02-20 | 美商·惠普公司 | Method and device for checking close of switch |
| CN1755867A (en) * | 2004-09-27 | 2006-04-05 | 中兴通讯股份有限公司 | DC fuse detector for power supply system |
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2007
- 2007-05-18 CN CN2007100743979A patent/CN101145805B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3940571A (en) * | 1974-11-04 | 1976-02-24 | Gte Sylvania Incorporated | Drive circuitry with error detection |
| CN1336659A (en) * | 2000-05-17 | 2002-02-20 | 美商·惠普公司 | Method and device for checking close of switch |
| CN1755867A (en) * | 2004-09-27 | 2006-04-05 | 中兴通讯股份有限公司 | DC fuse detector for power supply system |
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