CN117310562A - A device and method for electrical contact detection of welded metal leads - Google Patents
A device and method for electrical contact detection of welded metal leads Download PDFInfo
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- CN117310562A CN117310562A CN202311112264.1A CN202311112264A CN117310562A CN 117310562 A CN117310562 A CN 117310562A CN 202311112264 A CN202311112264 A CN 202311112264A CN 117310562 A CN117310562 A CN 117310562A
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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
- G01R31/50—Testing of electric apparatus, lines, cables or components for short-circuits, continuity, leakage current or incorrect line connections
- G01R31/66—Testing of connections, e.g. of plugs or non-disconnectable joints
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- General Physics & Mathematics (AREA)
- Testing Of Short-Circuits, Discontinuities, Leakage, Or Incorrect Line Connections (AREA)
Abstract
The invention provides a welding metal connecting wire electric contact detection device and method, the invention connects an inter-frequency voltmeter, an inter-frequency ammeter and a welding wire, two ends of a short-circuit wire are respectively connected with two welding wires, thereby a component, two welding metal connecting wires, two welding wires and a short-circuit wire form an electric loop, an inter-frequency power supply supplies alternating current to a magnetic flux ring, the short-circuit wire excites an inter-frequency electric induction signal, the inter-frequency ammeter collects the current value of a test wire, the inter-frequency voltmeter collects the voltage values at two ends of the short-circuit wire, the resistance of the welding wire and the welding metal connecting wire contact point is calculated and obtained according to the law of electromagnetic induction and ohm law, and whether the electric contact between the welding wire and the welding metal connecting wire is qualified is judged according to the resistance of the welding wire and the welding metal connecting wire contact point. The invention can search defects in the welding stage without considering complex circuits behind the welding plates at two sides of the welding metal connecting wire, and has high detection efficiency and high accuracy.
Description
Technical Field
The invention relates to the technical field of short circuit lead connection detection, in particular to a device and a method for detecting electrical contact of a welding metal lead.
Background
In electronic devices, for bridging or space connection, metal wire members such as gold and aluminum are often used to bond electrodes on integrated circuit silicon chips to lead frames to electrically connect the electrodes to each other, thereby realizing the purpose of conducting electrical signals. In the actual manufacturing and device module installation processes, electrical connection failure is often caused by loosening of welding points, virtual connection and the like, and element module failure is caused. The traditional detection means is that the defects are searched by checking the excitation, response and other parameter analysis of the device after the components are welded and assembled, so that the efficiency is low and the precision is poor.
Disclosure of Invention
Aiming at the problems mentioned in the background art, the invention provides a device and a method for detecting the electrical contact of a welding metal connecting wire, which can carry out nondestructive testing on the electrical connection state of an element wire in the welding stage and before debugging, and has the advantages of simple and convenient operation and high efficiency.
In order to achieve the technical purpose, the invention adopts the following technical scheme:
the utility model provides a weld metal wire electrical contact detection device, including components and parts, bonding pad and weld metal wire, the both ends of components and parts are connected with a bonding pad through a weld metal wire respectively, two bonding pads are connected respectively at a short circuit wire both ends, thereby make components and parts, two weld metal wires, two bonding pads and short circuit wire form the electrical circuit, detection device still includes voltage-current detection device, voltage-current detection device includes the inter-frequency ammeter, inter-frequency voltmeter and test wire, the inter-frequency ammeter connects on test wire, test wire both ends are connected at the short circuit wire both ends, inter-frequency voltmeter is parallelly connected with the inter-frequency ammeter for detect short circuit wire both ends voltage, detection device still includes excitation device, excitation device is used for the excitation to short circuit wire out the inter-frequency electric induction signal.
The voltage and current detection device further comprises a first conductive probe and a second conductive probe, the first conductive probe is fixed at one end of the test lead, the second conductive probe is fixed at the other end of the test lead, and the test lead is in contact with the bonding pad through the first conductive probe and the second conductive probe, so that the test lead is electrically connected with two ends of the short-circuit lead.
The excitation device comprises a magnetic flux ring and an inter-frequency power supply, the inter-frequency power supply is communicated with the magnetic flux ring, the short circuit lead wire penetrates through the inner ring of the magnetic flux ring, the inter-frequency power supply can enable the magnetic flux ring to be electrified with alternating current, and the magnetic flux ring excites an inter-frequency electric induction signal at the short circuit lead wire.
In order to optimize the technical scheme, the specific measures adopted further comprise:
the method for detecting the electrical contact of the welding metal connecting wire comprises the following steps of: the inter-frequency power supply supplies alternating current to the magnetic flux ring, the short circuit lead excites an inter-frequency electric induction signal, the inter-frequency ammeter collects current values of the test lead, the inter-frequency ammeter collects voltage values of two ends of the short circuit lead, the resistance of a contact point of the bonding pad and the welding metal lead is calculated and obtained according to the law of electromagnetic induction and ohm law, and whether the electrical contact between the bonding pad and the welding metal lead is qualified or not is judged according to the resistance of the contact point of the bonding pad and the welding metal lead.
The specific method for calculating and obtaining the resistance of the contact point of the bonding pad and the welding metal connecting wire according to the law of electromagnetic induction and the law of ohm comprises the following steps:
the inter-frequency power supply supplies alternating current to the magnetic flux ring twice, the frequencies are F1 and F2 respectively, the voltages induced by the inter-frequency voltmeter are U_F1 and U_F2 respectively, the currents induced by the inter-frequency voltmeter are I_F1 and I_F2 respectively,
z_f1=u_f1/i_f1= ((r0+r1)/(2 pi×f1×l)/(2)/(0.5) (1)
Z_f2=u_f2/i_f2= ((r0+r1)/(2 pi×f2×l)/(2)/(0.5) (2)
The combination formula (1) and the formula (2) are as follows:
r0= ((F2≡2X Z_F1≡2-F1≡2X Z_F2≡2)/(F2≡2-F1≡2))0.5-R1 formula (3)
R2=4000 ρl/(pi×d≡2) formula (4)
R3=R0-R2
Wherein Z_F1 is the impedance of the short circuit lead at the frequency F1, Z_F2 is the impedance of the short circuit lead at the frequency F2, R0 is the sum of the contact point of the bonding pad and the bonding metal lead and the resistance value of the bonding metal lead, R1 is the resistance value of the voltage and current detection device, R2 is the theoretical resistance value of the bonding metal lead, L is the length of the bonding metal lead, ρ is the resistivity of the bonding metal lead, D is the diameter of the bonding metal lead, and R3 is the resistance of the contact point of the bonding pad and the bonding metal lead.
When R3 > 0.2R2, the electrical contact of the welding metal connecting wire is judged to be bad.
The invention has the beneficial effects that:
1. the invention designs the short circuit lead, so that the components and the short circuit lead to be tested form an annular electric loop through the bonding pad, the coupling excitation unit penetrates the short circuit lead and forms a magnetic flux closed loop, induced voltages with different frequencies are excited through the different-frequency power supply, the annular channel response current is tested, the obtained resistances of the short circuit lead to be tested and the bonding pad are calculated according to the law of electromagnetic induction and ohm law, and the welding electric connection state is judged through the resistance value.
2. The invention can search defects in the welding stage without the need of finishing inspection of welding and assembling components and without considering complex circuits behind welding plates on two sides of a welding metal lead, and has high detection efficiency and high accuracy.
Drawings
FIG. 1 is a schematic diagram of a bond pad and shorting pin configuration of the present invention;
FIG. 2 is a schematic diagram of an electrical circuit;
fig. 3 is a schematic structural view of the present invention.
Name of the label in the figure: a bonding pad 1, a short-circuit lead 2, a different-frequency ammeter 3, a different-frequency voltmeter 4, an excitation device 5, a magnetic flux ring 51, a different-frequency power supply 52, a welding metal lead 6 and a test lead 7.
Detailed Description
In order to make the objects, technical solutions and advantages of the present application more apparent, the present application is described and illustrated below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the present application. All other embodiments, which can be made by one of ordinary skill in the art without undue burden on the person of ordinary skill in the art based on the embodiments provided herein, are intended to be within the scope of the present application.
It is apparent that the drawings in the following description are only some examples or embodiments of the present application, and it is possible for those of ordinary skill in the art to apply the present application to other similar situations according to these drawings without inventive effort. Moreover, it should be appreciated that while such a development effort might be complex and lengthy, it would nevertheless be a routine undertaking of design, fabrication, or manufacture for those of ordinary skill having the benefit of this disclosure, and thus should not be construed as having the benefit of this disclosure.
Reference in the specification to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the application. The appearances of such phrases in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. It is to be expressly and implicitly understood by those of ordinary skill in the art that the embodiments described herein can be combined with other embodiments without conflict.
Unless defined otherwise, technical or scientific terms used herein should be given the ordinary meaning as understood by one of ordinary skill in the art to which this application belongs. Reference to "a," "an," "the," and similar terms herein do not denote a limitation of quantity, but rather denote the singular or plural. The terms "comprising," "including," "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, article, or apparatus that comprises a list of steps or elements is not limited to only those listed or may include additional steps or elements not expressly listed or inherent to such process, method, article, or apparatus. The terms "connected," "coupled," and the like in this application are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. The term "plurality"/"a number" as used herein refers to two or more. "and/or" describes an association relationship of an association object, meaning that there may be three relationships, e.g., "a and/or B" may mean: a exists alone, A and B exist together, and B exists alone. The character "/" generally indicates that the context-dependent object is an "or" relationship. The terms "first," "second," "third," and the like, as used herein, are merely distinguishing between similar objects and not representing a particular ordering of objects.
Fig. 1 is a schematic diagram of a pad and a short-circuit lead, and the space bridging of a circuit is realized through the short-circuit lead, and the equivalent circuit structure is shown in fig. 2.
The invention relates to a welding metal connecting wire electric contact detection device which is developed for detecting whether the electric contact between a welding pad 1 and a welding metal connecting wire 6 is qualified or not, and mainly comprises the structures of the welding pad 1, a short-circuit lead 2, an inter-frequency ammeter 3, an inter-frequency voltmeter 4, a magnetic flux ring 51, an inter-frequency power supply 52 and the like.
The inter-frequency ammeter 3 and the inter-frequency voltmeter 4 are connected with a first conductive probe and a second conductive probe through test leads 7, the first conductive probe and the second conductive probe can be respectively contacted with the two bonding pads 1, the first conductive probe and the second conductive probe are connected with the inter-frequency ammeter 3 and the inter-frequency voltmeter 4 through the test leads 7, so that the inter-frequency ammeter 3 detects the current value of the test leads 7, the inter-frequency voltmeter 4 detects the voltage between two ends of the short-circuit lead 2,
the inter-frequency power supply 52 is communicated with the magnetic flux ring 51, the short-circuit lead wire 2 penetrates through the inner ring of the magnetic flux ring 51, the inter-frequency power supply 52 can enable the magnetic flux ring 51 to be powered with alternating current, and the magnetic flux ring 51 excites an inter-frequency electric induction signal at the short-circuit lead wire 2.
A method of detecting electrical contact of a soldered metal wire bond comprising:
step one: the inter-frequency ammeter 3 and the inter-frequency voltmeter 4 are connected with the bonding pads 1 through test leads and probes, two ends of a component are respectively connected with one bonding pad 1 through one welding metal bonding wire 6, and two ends of one short circuit lead 2 are respectively connected with two bonding pads 1, so that the component, the two welding metal bonding wires 6, the two bonding pads 1 and the short circuit lead 2 form an electric loop. The voltage and current detecting device is connected with the bonding pad 1 by a test probe through a test lead, and the electrical connection state is confirmed, specifically:
connecting the test lead with the inter-frequency ammeter 3 and two ends of the voltmeter, connecting the test lead with the inter-frequency ammeter 3 in series, and shorting the test lead with the inter-frequency voltmeter 4;
(2) Touching and electrically connecting a first probe of the voltage and current detection device with one side bonding pad 1 of the short circuit lead 2, and checking the electric connection state;
(3) The second probe of the voltage and current detecting device is touched and electrically connected to the other side pad 1 of the short-circuited lead 2, and the electrical connection state is checked.
Step two: the magnetic flux ring 51 is connected with a different-frequency power supply, penetrates into the short-circuit lead 2 and forms a magnetic flux closed loop, excites a different-frequency electric induction signal to the annular electric loop, and tests induction current, specifically:
(1) The corresponding frequency is F1 excitation current, the test induced voltage is U_F1, and the test induced current is I_F1;
(2) The corresponding frequency is F2 excitation current, the test induced voltage is U_F2, and the test induced current is I_F2.
Step three: and calculating the resistance of the tested short circuit lead 2 and judging defects. The short-circuit lead 2 and the contact resistance R0 with the pad 1 were calculated as follows:
z_f1=u_f1/i_f1= ((r0+r1)/(2 pi×f1×l)/(2)/(0.5) (1)
Z_f2=u_f2/i_f2= ((r0+r1)/(2 pi×f2×l)/(2)/(0.5) (2)
The combination formula (1) and the formula (2) are as follows:
r0= ((F2≡2X Z_F1≡2-F1≡2X Z_F2≡2)/(F2≡2-F1≡2))0.5-R1 formula (3)
R2=4000 ρl/(pi×d≡2) formula (4)
R3=R0-R2
Wherein z_f1 is the impedance of the short-circuit lead 2 at the frequency F1, z_f2 is the impedance of the short-circuit lead 2 at the frequency F2, R0 is the sum of the contact point of the bonding pad 1 and the bonding metal lead 6 and the resistance value of the bonding metal lead 6, R1 is the resistance value of the voltage and current detection device, R2 is the theoretical resistance value of the bonding metal lead 6, L is the length of the bonding metal lead 6, ρ is the resistivity of the bonding metal lead 6, D is the diameter of the bonding metal lead 6, and R3 is the resistance of the contact point of the bonding pad 1 and the bonding metal lead 6.
When R3 > 0.2R2, the electrical contact of the welding metal connecting wire is judged to be bad.
While preferred embodiments of the present application have been described, additional variations and modifications in those embodiments may occur to those skilled in the art once they learn of the basic inventive concepts. It is therefore intended that the following claims be interpreted as including the preferred embodiments and all such alterations and modifications as fall within the scope of the application.
It will be apparent to those skilled in the art that various modifications and variations can be made in the present application without departing from the spirit or scope of the application. Thus, if such modifications and variations of the present application fall within the scope of the claims and the equivalents thereof, the present application is intended to cover such modifications and variations.
Claims (6)
1. The utility model provides a welding metal wire electrical contact detection device, includes components and parts, pad (1) and welding metal wire (6), the both ends of components and parts respectively be connected characterized by through a welding metal wire (6) and a pad (1): two bonding pads (1) are connected respectively at two ends of a short-circuit lead (2) to make components and parts, two welded metal connect lead (6), two bonding pads (1) and short-circuit lead (2) form the electrical loop, detection device still includes voltage and current detection device, voltage and current detection device include pilot frequency ammeter (3), pilot frequency voltmeter (4) and test lead (7), pilot frequency ammeter (3) connect on test lead (7), test lead (7) both ends are connected at short-circuit lead (2) both ends, pilot frequency voltmeter (4) and pilot frequency ammeter (3) parallelly connected for detect short-circuit lead (2) both ends voltage, detection device still includes excitation device (5), excitation device (5) be used for exciting pilot frequency electric induction signal to short-circuit lead (2).
2. The electrical contact detection device for a solder wire according to claim 1, wherein: the voltage and current detection device also comprises a first conductive probe and a second conductive probe, wherein the first conductive probe is fixed at one end of the test lead (7), the second conductive probe is fixed at the other end of the test lead (7), and the test lead (7) is in contact with the bonding pad (1) through the first conductive probe and the second conductive probe, so that the electrical connection between the test lead (7) and the two ends of the short-circuit lead (2) is realized.
3. The electrical contact detection device for a solder wire according to claim 2, wherein: the exciting device (5) comprises a magnetic flux ring (51) and a different-frequency power supply (52), the different-frequency power supply (52) is communicated with the magnetic flux ring (51), the short circuit lead (2) penetrates through the inner ring of the magnetic flux ring (51), the different-frequency power supply (52) can enable the magnetic flux ring (51) to be electrified with alternating current, and the magnetic flux ring (51) excites different-frequency electric induction signals on the short circuit lead (2).
4. A method of detecting electrical contact of a soldered metal wire, comprising: use of the device for detecting electrical contact of a soldered metal wire as claimed in claim 3, the detection method being: the inter-frequency power supply (52) is used for supplying alternating current to the magnetic flux ring (51), the short-circuit lead (2) is used for exciting an inter-frequency electric induction signal, the inter-frequency ammeter (3) is used for collecting current values of the test lead (7), the inter-frequency voltmeter (4) is used for collecting voltage values at two ends of the short-circuit lead (2), the resistance of the contact point of the bonding pad (1) and the welding metal lead (6) is obtained through calculation according to the law of electromagnetic induction and the ohm law, and whether the electrical contact between the bonding pad (1) and the welding metal lead (6) is qualified or not is judged according to the resistance of the contact point of the bonding pad (1) and the welding metal lead (6).
5. A method of detecting electrical contact of a solder metal wire according to claim 4, wherein: the specific method for calculating and obtaining the resistance of the contact point of the bonding pad (1) and the welding metal connecting wire (6) according to the law of electromagnetic induction and ohm law comprises the following steps:
the inter-frequency power supply (52) is used for supplying alternating current to the magnetic flux ring (51) twice, the frequencies are F1 and F2 respectively, the voltages induced by the inter-frequency voltmeter (4) are U_F1 and U_F2 respectively, the currents induced by the inter-frequency ammeter (3) are I_F1 and I_F2 respectively,
z_f1=u_f1/i_f1= ((r0+r1)/(2 pi×f1×l)/(2)/(0.5) (1)
Z_f2=u_f2/i_f2= ((r0+r1)/(2 pi×f2×l)/(2)/(0.5) (2)
The combination formula (1) and the formula (2) are as follows:
r0= ((F2≡2X Z_F1≡2-F1≡2X Z_F2≡2)/(F2≡2-F1≡2))0.5-R1 formula (3)
R2=4000 ρl/(pi×d≡2) formula (4)
R3=R0-R2
Wherein Z_F1 is the impedance of the short-circuit lead (2) at the frequency F1, Z_F2 is the impedance of the short-circuit lead (2) at the frequency F2, R0 is the sum of the contact point of the bonding pad (1) and the bonding metal lead (6) and the resistance value of the bonding metal lead (6), R1 is the resistance value of the voltage and current detection device, R2 is the theoretical resistance value of the bonding metal lead (6), L is the length of the bonding metal lead (6), ρ is the resistivity of the bonding metal lead (6), D is the diameter of the bonding metal lead (6), and R3 is the resistance of the contact point of the bonding pad (1) and the bonding metal lead (6).
6. A method of detecting electrical contact of a solder metal wire according to claim 5, wherein: when R3 > 0.2R2, it is judged that the electrical contact of the bonding wire is poor.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311112264.1A CN117310562A (en) | 2023-08-31 | 2023-08-31 | A device and method for electrical contact detection of welded metal leads |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311112264.1A CN117310562A (en) | 2023-08-31 | 2023-08-31 | A device and method for electrical contact detection of welded metal leads |
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| CN117310562A true CN117310562A (en) | 2023-12-29 |
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Application publication date: 20231229 |