CN213302436U

CN213302436U - CAF test fixture

Info

Publication number: CN213302436U
Application number: CN202022063798.8U
Authority: CN
Inventors: 余军; 陈永华
Original assignee: GCI Science and Technology Co Ltd; Zhuhai GCI Science and Technology Co Ltd
Current assignee: GCI Science and Technology Co Ltd; Zhuhai GCI Science and Technology Co Ltd
Priority date: 2020-09-18
Filing date: 2020-09-18
Publication date: 2021-05-28
Anticipated expiration: 2030-09-18

Abstract

The utility model discloses a CAF test fixture, include support, constant voltage power supply and survey test panel. Be equipped with anodal terminal and negative terminal on surveying the board, anodal terminal and negative terminal respectively with the anodal and negative pole electric connection of constant voltage power supply, be equipped with a plurality of test branches between anodal terminal and the negative terminal, every test branch all includes a pair of test pad and definite value resistance, second test pad and definite value resistance's first end electric connection, first test pad reaches the both ends as test branch are respectively with anodal terminal and negative terminal electric connection, and definite value resistance's both ends are connected with voltmeter anodal pad and voltmeter negative terminal pad respectively. According to the CAF test fixture of the technical scheme, the voltage and the current flowing through the PCB are limited through the constant value resistor, the conductive anode wire is prevented from being broken due to overlarge current in the test process, the test result is accurate, the structure is simple, the manufacturing is easy, and the manufacturing cost is low.

Description

CAF test fixture

Technical Field

The utility model relates to a circuit board test field, in particular to CAF test fixture.

Background

With the development of electronic products tending to small models, the design of the PCB board is more and more intensive, and the intensive design causes the insulation distances between holes, between holes and bonding pads and between bonding pads to be reduced, so that the products have poor phenomena of short circuit or insulation and the like after being used for a period of time at a client. To monitor this phenomenon, PCB manufacturers periodically perform SIR (surface insulation resistance) tests and CAF (conductive anode filament) tests on PCB boards during the manufacturing process.

The special test equipment in the market has high accuracy and good repeatability, but is expensive. Most small and medium-sized enterprises can directly test the voltage at the specified temperature and humidity by testing the spot welding lead, and can not know whether the test sample fails in the test process in time.

SUMMERY OF THE UTILITY MODEL

The utility model discloses aim at solving one of the technical problem that exists among the prior art at least. Therefore, the utility model provides a CAF test fixture can restrict test current, prevents that the heat fusing that electrically conductive anode wire produced by the heavy current from leading to the test result inaccurate, and low in manufacturing cost.

According to the utility model discloses a CAF test fixture, include: a support; the stabilized voltage power supply is placed on the bracket; survey test panel, set up in on the support, be equipped with anodal terminal and negative terminal on surveying the test panel, anodal terminal reaches negative terminal respectively with the positive and negative pole electric connection of constant voltage power supply, anodal terminal reaches be equipped with a plurality of test branches between the negative terminal, every the test branch road all includes a pair of test pad and definite value resistance, second test pad and definite value resistance's first end electric connection, first test pad reaches definite value resistance's second end is as the both ends of test branch road respectively with anodal terminal reaches negative terminal electric connection, definite value resistance's both ends are connected with voltmeter anodal pad and voltmeter negative terminal pad respectively.

According to the utility model discloses CAF test fixture has following beneficial effect at least: the testing point of the PCB to be tested is connected with the testing pad on the testing board, the voltmeter is connected with the positive pad and the negative pad of the voltmeter, and each testing branch can test one testing point. The constant value resistor divides voltage and limits current, so that the current flowing through the test point is not too large, and a conductive anode wire formed by copper ion migration is not blown, so that the test result is not accurate.

According to the utility model discloses a some embodiments, the support is including two-layer, constant voltage power supply place in the lower floor of support, the upper strata of support be equipped with the upper strata be the grillage of certain contained angle, survey test panel set up in on the grillage.

According to some embodiments of the utility model, the upper strata reaches all be equipped with insulating backing plate on the lower floor.

According to the utility model discloses a some embodiments, first test pad the second test pad the positive pad of voltmeter reaches voltmeter negative pole pad all welds and has the connection pin gang.

According to the utility model discloses a some embodiments, survey test panel from inside to outside and include double sided board and solder mask.

According to some embodiments of the present invention, the surface of the test board is treated by spraying tin on the surface.

Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.

Drawings

The above and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

fig. 1 is a schematic front structural view of a CAF test fixture according to an embodiment of the present invention;

fig. 2 is a schematic side view of a CAF test fixture according to an embodiment of the present invention;

fig. 3 is a schematic diagram of a test board according to an embodiment of the present invention;

fig. 4 is a schematic circuit diagram of the test board according to the embodiment of the present invention.

Reference numerals:

bracket 100, plate frame 110;

a regulated power supply 200;

the testing board 300, a testing branch 310, a first testing pad 311, a second testing pad 312, a constant resistor 313, a voltmeter anode pad 314, a voltmeter cathode pad 315, an anode terminal 320, and a cathode terminal 330.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are exemplary only for the purpose of explaining the present invention, and should not be construed as limiting the present invention.

In the description of the present invention, it should be understood that the orientation or positional relationship indicated with respect to the orientation description, such as up, down, front, rear, left, right, etc., is based on the orientation or positional relationship shown in the drawings, and is only for convenience of description and simplification of description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention.

In the description of the present invention, a plurality of means are one or more, a plurality of means are two or more, and the terms greater than, less than, exceeding, etc. are understood as not including the present number, and the terms greater than, less than, within, etc. are understood as including the present number. If the first and second are described for the purpose of distinguishing technical features, they are not to be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated or implicitly indicating the precedence of the technical features indicated.

In the description of the present invention, unless there is an explicit limitation, the words such as setting, installation, connection, etc. should be understood in a broad sense, and those skilled in the art can reasonably determine the specific meanings of the above words in combination with the specific contents of the technical solution.

Referring to fig. 1, fig. 3 and 4 are CAF test fixtures according to embodiments of the present invention, which includes a bracket 100, a voltage-stabilized power supply 200 and a test board 300. The regulated power supply 200 is placed on the stand 100, and the test board 300 is disposed on the stand 100. Referring to fig. 3 and 4, the testing board 300 is provided with a positive terminal 320 and a negative terminal 330, the positive terminal 320 is electrically connected to the positive electrode of the regulated power supply 200, and the negative terminal 330 is electrically connected to the negative electrode of the regulated power supply 200. A plurality of test branches 310 are arranged between the positive terminal 320 and the negative terminal 330, each test branch 310 includes a pair of test pads and a fixed value resistor 313, wherein the second test pad 312 is electrically connected with a first end of the fixed value resistor 313, the first test pad 311 and a second end of the fixed value resistor 313 are used as two ends of the test branch 310 to be electrically connected with the positive terminal 320 and the negative terminal 330 respectively, two ends of the fixed value resistor 313 are also electrically connected with the positive pad 314 and the negative pad 315 of the voltmeter respectively, and the positive pad 314 and the negative pad 315 of the voltmeter are used for connecting the voltmeter respectively. When the test device is used, the test points on the PCB to be tested are respectively electrically connected with the first test pad 311 and the second test pad 312, the PCB to be tested is connected into the test branch 310 in series, the voltmeter is connected in parallel at two ends of the constant value resistor 313 through the voltmeter anode pad 314 and the voltmeter cathode pad 315, the output value of the stabilized voltage power supply 200 and the resistance value of the constant value resistor 313 are known, the resistance value of the PCB can be calculated, and the resistance value of the PCB can be compared with a reference value to know whether the PCB has conductive anode wires generated by copper ion migration, so that poor insulation or short circuit of the PCB part is caused. Because the constant value resistor 313 shares voltage and limits the current value flowing through the PCB, the conductive anode wire on the PCB can be effectively prevented from being fused by heat generated by large current, so that the test result is normal and inaccurate. According to the utility model discloses CAF test fixture still has simple structure, advantage that low in manufacturing cost. It can be understood that the resistance of the fixed resistor 313 should be selected to be suitable according to the power that the PCB to be tested can bear. The resistance of the fixed resistor 313 on each test branch 310 may be the same or different, so as to implement the test for PCBs with different powers.

The CAF test fixture according to an embodiment of the present invention is described in detail with a specific embodiment with reference to fig. 1 to 3. It is to be understood that the following description is illustrative only and is not intended as a specific limitation on the invention.

Referring to fig. 1 and 2, in this embodiment, the support 100 includes two layers, the regulated power supply 200 is disposed on the lower layer of the support 100, the upper layer of the support 100 is disposed with the board frame 110 having a certain included angle with the upper layer, the test board 300 is disposed on the board frame 110, and during testing, the PCB board to be tested can be disposed on the upper layer of the support 100, so that the PCB board to be tested and the test board 300 are electrically connected. In the present embodiment, the plate frame 110 forms an included angle of 110 degrees with the upper layer. In this embodiment, the bracket 100 is made of stainless steel, so that insulating pads are disposed on both the upper layer and the lower layer of the bracket 100.

Referring to fig. 3, in the present embodiment, there are 20 testing branches 310 on the testing board 300, so that the testing of 20 PCB boards can be realized. The test board 300 is a PCB made of a double-sided board, both sides of the double-sided board are provided with solder resists, and both sides of the double-sided board are subjected to surface tin spraying treatment, so that a layer of tin layer is arranged on each of the test pad, the voltmeter positive pad 314 and the voltmeter negative pad 315, and welding is facilitated. In this embodiment, the PCB is sprayed with lead-free tin. In this embodiment, in order to facilitate the connection with the PCB to be tested, the test pad, the voltmeter positive pad 314 and the voltmeter negative pad 315 are all provided with a connection pin header for facilitating the connection.

According to the CAF test fixture of the technical scheme, the voltage and the current flowing through the PCB are limited through the fixed value resistor 313, the conductive anode wire is prevented from being broken due to overlarge current in the test process, the test result is accurate, the structure is simple, the manufacturing is easy, and the manufacturing cost is low.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an illustrative embodiment," "an example," "a specific example," or "some examples" or the like mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

The embodiments of the present invention have been described in detail with reference to the accompanying drawings, but the present invention is not limited to the above embodiments, and various changes can be made without departing from the spirit of the present invention within the knowledge of those skilled in the art.

Claims

1. The utility model provides a CAF test fixture which characterized in that includes:

a support;

the stabilized voltage power supply is placed on the bracket;

survey test panel, set up in on the support, be equipped with anodal terminal and negative terminal on surveying the test panel, anodal terminal reaches negative terminal respectively with the positive and negative pole electric connection of constant voltage power supply, anodal terminal reaches be equipped with a plurality of test branches between the negative terminal, every the test branch road all includes a pair of test pad and definite value resistance, second test pad and definite value resistance's first end electric connection, first test pad reaches definite value resistance's second end is as the both ends of test branch road respectively with anodal terminal reaches negative terminal electric connection, definite value resistance's both ends are connected with voltmeter anodal pad and voltmeter negative terminal pad respectively.

2. The CAF test fixture of claim 1, wherein the support comprises two layers, the stabilized voltage power supply is placed on the lower layer of the support, a plate frame forming a certain included angle with the upper layer is arranged on the upper layer of the support, and the test board is arranged on the plate frame.

3. The CAF test fixture of claim 2, wherein said upper layer and said lower layer are provided with insulating pads.

4. The CAF test fixture of claim 1, wherein the first test pad, the second test pad, the voltmeter anode pad and the voltmeter cathode pad are welded with a connection pin header.

5. The CAF test fixture of claim 1, wherein the test board comprises a double-sided board and a solder mask layer from inside to outside.

6. The CAF test fixture of claim 1, wherein the surface of the test board is subjected to a surface tin spraying treatment.