CN108362993A - A kind of measuring device and its measurement method for multilayer wire girth sheets - Google Patents
A kind of measuring device and its measurement method for multilayer wire girth sheets Download PDFInfo
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- CN108362993A CN108362993A CN201810056374.3A CN201810056374A CN108362993A CN 108362993 A CN108362993 A CN 108362993A CN 201810056374 A CN201810056374 A CN 201810056374A CN 108362993 A CN108362993 A CN 108362993A
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/28—Testing of electronic circuits, e.g. by signal tracer
- G01R31/2801—Testing of printed circuits, backplanes, motherboards, hybrid circuits or carriers for multichip packages [MCP]
- G01R31/281—Specific types of tests or tests for a specific type of fault, e.g. thermal mapping, shorts testing
- G01R31/2812—Checking for open circuits or shorts, e.g. solder bridges; Testing conductivity, resistivity or impedance
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- Microelectronics & Electronic Packaging (AREA)
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- General Physics & Mathematics (AREA)
- Measurement Of Current Or Voltage (AREA)
- Geophysics And Detection Of Objects (AREA)
Abstract
The invention discloses a kind of measuring devices for multilayer wire girth sheets, including two magnetic field output probes, the magnetic direction of two magnetic field output probes is mutually perpendicular to, the input terminal of each magnetic field output probe is connected with independent signal generator, two signal generators export sine wave signal, and signal frequency is respectively 20~30Hz and 150~200Hz；Further include a signal output apparatus, the output end of signal output apparatus is connected to controller, and signal output end road acquisition multilayer wire girth sheets powers on sense tank voltage, voltage value is delivered to controller.The present invention can improve the deficiencies in the prior art, improve the accuracy detected for pcb board.
Description
Technical field
The present invention relates to pcb board detection technique field, especially a kind of measuring devices and its survey for multilayer wire girth sheets
Amount method.
Background technology
The internal layer circuit of multilayer PBC plates can not be observed intuitively, can only determine opening for internal layer by electromotive checking
Short-circuit state, but the internal layer circuit of some wiring boards is jagged or has the residual copper of redundance, but do not interfere with the company of circuit
Logical, this problem PCB can not be tested out by electrical measurement process, at this moment can be sentenced with the method for inductance measurement
Not.Chinese utility model patent CN 205809224U disclose a kind of contactless PCB coil turn-to-turn short circuit detection device, lead to
It crosses and pcb board is placed in alternating magnetic field, the energy storage by measuring pcb board inductance changes, and is detected to pcb board.But this
The sampling precision of kind detection device is poor, and measuring result error is big.
Invention content
The technical problem to be solved in the present invention is to provide a kind of measuring devices and its measurement method for multilayer wire girth sheets, can
The deficiencies in the prior art are solved, the accuracy detected for pcb board is improved.
In order to solve the above technical problems, the technical solution used in the present invention is as follows.
A kind of measuring device for multilayer wire girth sheets, including two magnetic field output probes, what two magnetic field outputs were popped one's head in
Magnetic direction is mutually perpendicular to, and the input terminal of each magnetic field output probe is connected with independent signal generator, and two signals occur
Device exports sine wave signal, and signal frequency is respectively 20~30Hz and 150~200Hz；Further include a signal output apparatus, letter
The output end of number output circuit is connected to controller, and signal output end road acquisition multilayer wire girth sheets powers on sense tank voltage, will be electric
Pressure value is delivered to controller.
Preferably, the positive that the input terminal of the signal output apparatus is connected to the first amplifier by first resistor inputs
End, the inverting input of the first amplifier are connected to the output end of the first amplifier, the anti-phase input of the first amplifier by second resistance
End is grounded by 3rd resistor, and the output end of the first amplifier is connected to the inverting input of the second amplifier by the 4th resistance, the
The normal phase input end of two amplifiers is connected to second by the 5th resistance eutral grounding, the inverting input of the second amplifier by the 6th resistance
The output end of amplifier, the output end of the second amplifier are connected to the normal phase input end of the first amplifier, the first amplifier by the 7th resistance
Output end pass through concatenated 8th resistance and the first capacitance connection to the normal phase input end of third amplifier, the 8th resistance and first
The 9th resistance eutral grounding, the reverse phase of third amplifier are passed through by the second capacity earth, the normal phase input end of third amplifier between capacitance
Input terminal is connected to the output end of third amplifier by the tenth resistance, and the inverting input of third amplifier is connect by eleventh resistor
Ground is connected to the base stage of the first triode, the base of the first triode by twelfth resistor between the 8th resistance and the first capacitance
Pole is connected to the collector of the first triode, and the collector of the first triode is connected to the output end of third amplifier, the one or three pole
The emitter of pipe is connected to the collector of the second triode by thirteenth resistor, and the base stage of the second triode passes through third capacitance
It is connected to the output end of third amplifier, the collector of the second triode passes through the 4th capacity earth, the emitter of the second triode
By the 5th capacity earth, the inverting input of the first amplifier is connected to the cathode of zener diode, the anode of zener diode
It is connected to the inverting input of third amplifier, the output end of third amplifier is connected to the output by the 14th resistance.
Preferably, the output end of the third amplifier, by the 6th capacity earth, the output end of third amplifier passes through
15 resistance are connected to the normal phase input end of four high guaily unit, and the inverting input of four high guaily unit is by the 16th resistance eutral grounding, and
The output end of four high guaily unit is connected to the inverting input of the 5th amplifier by the 17th resistance, and the normal phase input end of the 5th amplifier is logical
Cross the 18th resistance eutral grounding, the inverting input of the 5th amplifier is by the output end of the 7th capacitance connection to the 5th amplifier, and the 5th
The output end of amplifier is connected to the normal phase input end of four high guaily unit by the 19th resistance, and the output end of four high guaily unit passes through second
Ten resistance are connected to the base stage of third transistor, and the collector of third transistor is connected to the output, the transmitting of third transistor
Pole passes through the 8th capacity earth.
A kind of measurement method of the above-mentioned measuring device for multilayer wire girth sheets, includes the following steps：
A, two magnetic field output probes are alternately to multilayer wire girth sheets time alternating magnetic field；
B, signal output apparatus is acquired the energy storage variation of inductance in multilayer wire girth sheets, and be converted into after voltage signal by
It is delivered to controller after filtering noise reduction process；
C, controller judges the quality of lattice coil inner cord circuit according to voltage signal variation.
It is using advantageous effect caused by above-mentioned technical proposal：The present invention passes through the distribution in change magnetic field, profit
Pcb board is measured with the alternating magnetic field of orthogonal two different frequencies, can effectively reduce the shakiness of magnetic field state
Influence of fixed and pcb board placement location the deviation for testing result.The present invention is directed to the interference in signals transmission, weight
New to devise signal output apparatus, the signal amplification circuit that the first amplifier and the second amplifier form is used to be amplified signal,
Then noise reduction is carried out to output signal using the first order filter circuit of third amplifier composition.First triode and the second triode
The second season filter circuit of composition is used for carrying out secondary filter to remaining High-frequency Interference in output signal, to improve noise reduction effect
Fruit.Four high guaily unit and the 5th amplifier are used for carrying out third level filtering to output signal, for spike arteries and veins present in trap signal
Punching.
Description of the drawings
Fig. 1 is the schematic diagram of a specific implementation mode of the invention.
Fig. 2 is the circuit diagram of signal output apparatus in a specific implementation mode of the invention.
Specific implementation mode
The standardized element used in the present invention can commercially, and shaped piece is according to specification and attached drawing
Record can carry out customized, and the specific connection type of each part is all made of bolt ripe in the prior art, rivet, weldering
The conventional means such as connect, paste, this will not be detailed here.
Referring to Fig.1-2, it includes two magnetic field output probes 1, two magnetic field output probes 1 to invent a specific implementation mode
Magnetic direction be mutually perpendicular to, the input terminal of each magnetic field output probe 1 is connected with independent signal generator 2, two signals
Generator 2 exports sine wave signal, and signal frequency is respectively 20~30Hz and 150~200Hz；It further include a signal output electricity
The output end on road 3, signal output apparatus 3 is connected to controller 4, and signal output end road 3 acquires multilayer wire girth sheets and powers on sense energy storage
Voltage value is delivered to controller 4 by voltage.The input terminal IN of signal output apparatus 3 is connected to the first fortune by first resistor R1
The normal phase input end of A1 is put, the inverting input of the first amplifier A1 is connected to the output of the first amplifier A1 by second resistance R2
End, the inverting input of the first amplifier A1 are grounded by 3rd resistor R3, and the output end of the first amplifier A1 passes through the 4th resistance R4
It is connected to the inverting input of the second amplifier A2, the normal phase input end of the second amplifier A2 passes through the 5th resistance R5 ground connection, the second fortune
The inverting input for putting A2 is connected to the output end of the second amplifier A2 by the 6th resistance R6, and the output end of the second amplifier A2 passes through
7th resistance R7 is connected to the normal phase input end of the first amplifier A1, and the output end of the first amplifier A1 passes through concatenated 8th resistance R8
It is connected to the normal phase input end of third amplifier A3 with the first capacitance C1, passes through the second electricity between the 8th resistance R8 and the first capacitance C1
Hold C2 ground connection, by the 9th resistance R9 ground connection, the inverting input of third amplifier A3 passes through the normal phase input end of third amplifier A3
Tenth resistance R10 is connected to the output end of third amplifier A3, and the inverting input of third amplifier A3 is connect by eleventh resistor R11
Ground, is connected to the base stage of the first triode Q1 by twelfth resistor R12 between the 8th resistance R8 and the first capacitance C1, and the one or three
The base stage of pole pipe Q1 is connected to the collector of the first triode Q1, and the collector of the first triode Q1 is connected to third amplifier A3's
Output end, the emitter of the first triode Q1 are connected to the collector of the second triode Q2 by thirteenth resistor R13, and the two or three
The base stage of pole pipe Q2 is connected to the output end of third amplifier A3 by third capacitance C3, and the collector of the second triode Q2 passes through
Four capacitance C4 ground connection, by the 5th capacitance C5 ground connection, the inverting input of the first amplifier A1 connects the emitter of the second triode Q2
It is connected to the cathode of zener diode DZ, the anode of zener diode DZ is connected to the inverting input of third amplifier A3, third fortune
The output end for putting A3 is connected to the output OUT by the 14th resistance R14.The output end of third amplifier A3 passes through the 6th capacitance C6
Ground connection, the output end of third amplifier A3 are connected to the normal phase input end of four high guaily unit A4, four high guaily unit by the 15th resistance R15
The inverting input of A4 is connected to by the 16th resistance R16 ground connection, the output end of four high guaily unit A4 by the 17th resistance R17
The normal phase input end of the inverting input of 5th amplifier A5, the 5th amplifier A5 passes through the 18th resistance R18 ground connection, the 5th amplifier A5
Inverting input the output end of the 5th amplifier A5 is connected to by the 7th capacitance C7, the output end of the 5th amplifier A5 passes through the tenth
Nine resistance R19 are connected to the normal phase input end of four high guaily unit A4, and the output end of four high guaily unit A4 passes through the 20th resistance R20 connections
To the base stage of third transistor Q3, the collector of third transistor Q3 is connected to the output OUT, the emitter of third transistor Q3
Pass through the 8th capacitance C8 ground connection.
In addition, the emitter of third transistor Q3 is connected to by the 21st resistance R21 and the 9th capacitance C9 in parallel
The normal phase input end of the inverting input of 6th amplifier A6, the 6th amplifier A6 passes through the 22nd resistance R22 ground connection, the 6th amplifier
The inverting input of A6 is connected to the output end of the 6th amplifier A6 by concatenated 23rd resistance R23 and the tenth capacitance C10,
The output end of 6th amplifier A6 is connected to by the 24th resistance R24 between the 8th resistance R8 and the first capacitance C1.Pass through
The feedback circuit of six amplifier A6 compositions, can export quality with effective monitoring signal, improve signal output apparatus 3 and signal is exported
Automatic adjusument.
Wherein, first resistor R1 is 0.35k Ω, second resistance R2 is 1 k Ω, and 3rd resistor R3 is 5.5 k Ω, the 4th electricity
Resistance R4 is 1.5 k Ω, the 5th resistance R5 is 2 k Ω, the 6th resistance R6 is 10 k Ω, the 7th resistance R7 is 5.5 k Ω, the 8th electricity
Resistance R8 is 3 k Ω, the 9th resistance R9 is 12.5 k Ω, the tenth resistance R10 is 5 k Ω, eleventh resistor R11 is 8 k Ω, the tenth
Two resistance R12 are 3.5 k Ω, thirteenth resistor R13 is 7 k Ω, the 14th resistance R14 is 10 k Ω, the 15th resistance R15 is
0.5 k Ω, the 16th resistance R16 are 1.5 k Ω, the 17th resistance R17 is 9.5 k Ω, the 18th resistance R18 is 6 k Ω,
19 resistance R19 are 0.75 k Ω, the 20th resistance R20 is 4 k Ω, the 21st resistance R21 is 3.5 k Ω, the 22nd
Resistance R22 is 4.5 k Ω, the 23rd resistance is 0.25 k Ω, the 24th resistance R24 is 5.5 k Ω.First capacitance C1 is
200 μ F, the second capacitance C2 are 150 μ F, third capacitance C3 is 400 μ F, the 4th capacitance C4 is 100 μ F, the 5th capacitance C5 is 330 μ
F, the 6th capacitance C6 is 350 μ F, the 7th capacitance C7 is 250 μ F, the 8th capacitance C8 is 150 μ F, the 9th capacitance C9 is 100 μ F,
Ten capacitance C10 are 600 μ F.The breakdown value of zener diode DZ is 2V.
A kind of measurement method of the above-mentioned measuring device for multilayer wire girth sheets, includes the following steps：
A, two magnetic field output probes 1 are alternately to multilayer wire girth sheets time alternating magnetic field；
B, signal output apparatus 3 is acquired the energy storage variation of inductance in multilayer wire girth sheets, and is passed through after being converted into voltage signal
It is delivered to controller 4 after crossing filtering noise reduction process；
C, controller 4 judges the quality of lattice coil inner cord circuit according to voltage signal variation.
The present invention can effectively improve the accuracy in detection of PCB circuit board, realize that 97% or more defect detection rate is correct
Rate.
The above shows and describes the basic principles and main features of the present invention and the advantages of the present invention.The technology of the industry
Personnel are it should be appreciated that the present invention is not limited to the above embodiments, and the above embodiments and description only describe this
The principle of invention, without departing from the spirit and scope of the present invention, various changes and improvements may be made to the invention, these changes
Change and improvement all fall within the protetion scope of the claimed invention.The claimed scope of the invention by appended claims and its
Equivalent thereof.
Claims (4)
1. a kind of measuring device for multilayer wire girth sheets, it is characterised in that：Including two magnetic field output probes（1）, two magnetic
Field output probe（1）Magnetic direction be mutually perpendicular to, each magnetic field output probe（1）Input terminal be connected with independent signal hair
Raw device（2）, two signal generators（2）Sine wave signal is exported, signal frequency is respectively 20~30Hz and 150~200Hz；Also
Including a signal output apparatus（3）, signal output apparatus（3）Output end be connected to controller（4）, signal output end road
（3）Acquisition multilayer wire girth sheets powers on sense tank voltage, and voltage value is delivered to controller（4）.
2. the measuring device according to claim 1 for multilayer wire girth sheets, it is characterised in that：The signal output apparatus
（3）Input terminal（IN）Pass through first resistor（R1）It is connected to the first amplifier（A1）Normal phase input end, the first amplifier（A1）'s
Inverting input passes through second resistance（R2）It is connected to the first amplifier（A1）Output end, the first amplifier（A1）Inverting input
Pass through 3rd resistor（R3）Ground connection, the first amplifier（A1）Output end pass through the 4th resistance（R4）It is connected to the second amplifier（A2）'s
Inverting input, the second amplifier（A2）Normal phase input end pass through the 5th resistance（R5）Ground connection, the second amplifier（A2）Reverse phase it is defeated
Enter end and passes through the 6th resistance（R6）It is connected to the second amplifier（A2）Output end, the second amplifier（A2）Output end pass through the 7th electricity
Resistance（R7）It is connected to the first amplifier（A1）Normal phase input end, the first amplifier（A1）Output end pass through concatenated 8th resistance
（R8）With the first capacitance（C1）It is connected to third amplifier（A3）Normal phase input end, the 8th resistance（R8）With the first capacitance（C1）It
Between pass through the second capacitance（C2）Ground connection, third amplifier（A3）Normal phase input end pass through the 9th resistance（R9）Ground connection, third amplifier
（A3）Inverting input pass through the tenth resistance（R10）It is connected to third amplifier（A3）Output end, third amplifier（A3）It is anti-
Phase input terminal passes through eleventh resistor（R11）Ground connection, the 8th resistance（R8）With the first capacitance（C1）Between pass through twelfth resistor
（R12）It is connected to the first triode（Q1）Base stage, the first triode（Q1）Base stage be connected to the first triode（Q1）Collection
Electrode, the first triode（Q1）Collector be connected to third amplifier（A3）Output end, the first triode（Q1）Emitter
Pass through thirteenth resistor（R13）It is connected to the second triode（Q2）Collector, the second triode（Q2）Base stage pass through third
Capacitance（C3）It is connected to third amplifier（A3）Output end, the second triode（Q2）Collector pass through the 4th capacitance（C4）It connects
Ground, the second triode（Q2）Emitter pass through the 5th capacitance（C5）Ground connection, the first amplifier（A1）Inverting input be connected to
Zener diode（DZ）Cathode, zener diode（DZ）Anode be connected to third amplifier（A3）Inverting input, third
Amplifier（A3）Output end pass through the 14th resistance（R14）It is connected to the output（OUT）.
3. the measuring device according to claim 2 for multilayer wire girth sheets, it is characterised in that：The third amplifier（A3）
Output end pass through the 6th capacitance（C6）Ground connection, third amplifier（A3）Output end pass through the 15th resistance（R15）It is connected to
Four high guaily unit（A4）Normal phase input end, four high guaily unit（A4）Inverting input pass through the 16th resistance（R16）Ground connection, the 4th fortune
It puts（A4）Output end pass through the 17th resistance（R17）It is connected to the 5th amplifier（A5）Inverting input, the 5th amplifier（A5）
Normal phase input end pass through the 18th resistance（R18）Ground connection, the 5th amplifier（A5）Inverting input pass through the 7th capacitance（C7）
It is connected to the 5th amplifier（A5）Output end, the 5th amplifier（A5）Output end pass through the 19th resistance（R19）It is connected to the 4th
Amplifier（A4）Normal phase input end, four high guaily unit（A4）Output end pass through the 20th resistance（R20）It is connected to third transistor
（Q3）Base stage, third transistor（Q3）Collector be connected to the output（OUT）, third transistor（Q3）Emitter pass through
8th capacitance（C8）Ground connection.
4. a kind of measurement method of the measuring device for multilayer wire girth sheets described in claim 1-3, it is characterised in that including
Following steps：
A, two magnetic field output probes（1）Alternately to multilayer wire girth sheets time alternating magnetic field；
B, signal output apparatus（3）The energy storage variation of inductance in multilayer wire girth sheets is acquired, and after being converted into voltage signal
It is delivered to controller after filtered noise reduction process（4）；
C, controller（4）The quality of lattice coil inner cord circuit is judged according to voltage signal variation.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810056374.3A CN108362993B (en) | 2018-01-20 | 2018-01-20 | Measuring device and measuring method for multilayer coil plate |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810056374.3A CN108362993B (en) | 2018-01-20 | 2018-01-20 | Measuring device and measuring method for multilayer coil plate |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN108362993A true CN108362993A (en) | 2018-08-03 |
| CN108362993B CN108362993B (en) | 2020-08-18 |
Family
ID=63006509
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201810056374.3A Active CN108362993B (en) | 2018-01-20 | 2018-01-20 | Measuring device and measuring method for multilayer coil plate |
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| Country | Link |
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| CN (1) | CN108362993B (en) |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0961494A (en) * | 1995-08-21 | 1997-03-07 | Fuji Photo Film Co Ltd | Pattern for testing printed circuit board |
| CN1155082A (en) * | 1995-09-27 | 1997-07-23 | Lg产电株式会社 | Passive-element testing circuit for printed circuit |
| CN1403826A (en) * | 2001-09-12 | 2003-03-19 | 明碁电通股份有限公司 | Method of detecting short circuit of inner layer in multilayer printed circuit board |
| CN105958962A (en) * | 2016-06-07 | 2016-09-21 | 河北梅特电气设备有限公司 | Filtering circuit for lighting metering distribution box |
| CN205622840U (en) * | 2016-04-11 | 2016-10-05 | 迟明欣 | A speaker circuit for english show teaching aid |
| CN205809224U (en) * | 2016-06-15 | 2016-12-14 | 深圳市光彩凯宜电子开发有限公司 | Contactless PCB coil turn-to-turn short circuit detection device |
-
2018
- 2018-01-20 CN CN201810056374.3A patent/CN108362993B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0961494A (en) * | 1995-08-21 | 1997-03-07 | Fuji Photo Film Co Ltd | Pattern for testing printed circuit board |
| CN1155082A (en) * | 1995-09-27 | 1997-07-23 | Lg产电株式会社 | Passive-element testing circuit for printed circuit |
| CN1403826A (en) * | 2001-09-12 | 2003-03-19 | 明碁电通股份有限公司 | Method of detecting short circuit of inner layer in multilayer printed circuit board |
| CN205622840U (en) * | 2016-04-11 | 2016-10-05 | 迟明欣 | A speaker circuit for english show teaching aid |
| CN105958962A (en) * | 2016-06-07 | 2016-09-21 | 河北梅特电气设备有限公司 | Filtering circuit for lighting metering distribution box |
| CN205809224U (en) * | 2016-06-15 | 2016-12-14 | 深圳市光彩凯宜电子开发有限公司 | Contactless PCB coil turn-to-turn short circuit detection device |
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| Publication number | Publication date |
|---|---|
| CN108362993B (en) | 2020-08-18 |
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