CN101173973B - Method for detecting circuit on-and-off of flexible circuit board - Google Patents

Abstract

The invention discloses a detection method of circuit on-off of the flexible circuit board, and the flexible circuit board comprises a plurality of first golden fingers with smaller spacing at the upper part of the flexible circuit board, a plurality of second golden fingers with larger spacing at the lower part of the flexible circuit board, a plurality of solder pads arranged between the first golden fingers and the second golden fingers and a plurality of connecting wires for connection of the first golden fingers, the second golden fingers and the solder pads. The method is composed of the following steps: (1) the flexible circuit board is fixed on the on-off testing jig; (2) the conductive cloth is arranged on the first golden fingers of the flexible circuit board under test; (3) theon-off situation among the conductive cloth, all the second golden fingers and the solder pads are tested by a testing probe, further the on-off situation among the first golden fingers, all the second fingers and the solder pads are judged. The invention has the advantages that the testing probes of uncommon specifications are not used, so that the production cost and the production cycle of thetesting jigs are reduced effectively, and the service life of the testing jigs is improved.

Description

The circuit on-off detecting method of flexible PCB

Affiliated technical field

The present invention relates to a kind of circuit on-off detecting method of flexible PCB, relate in particular to a kind of low cost, the circuit on-off detecting method of flexible PCB fast and accurately.

Background technology

FPC (Flexible Printed Circuit Board) is a flexible printed circuit board, is the P.e.c. made from flexible insulating substrate, has the advantage that many rigid printed circuit boards do not possess.For example it can free bend, coiling, folding, can require to arrange arbitrarily according to space layout, and move arbitrarily and flexible, thereby reach integrated that the components and parts assembling is connected with lead at three dimensions.Utilize FPC can dwindle the volume of electronic product greatly, be suitable for the needs that electronic product develops to high density, miniaturization, highly reliable direction.Therefore, FPC has obtained using widely on field such as space flight, military affairs, mobile communication, laptop computer, computer peripheral equipment, PDA, digital camera or product.FPC also has good thermal diffusivity and weldability and is easy to advantages such as load, integrated cost be lower, and the design of soft or hard combination has also remedied flexible parent metal not enough slightly on the assembly load-bearing capacity to a certain extent.Flexible print circuit board has the branch of single face, two-sided and multilayer board.The base material that is adopted is based on polyimide copper clad lamination.This kind material thermal resistance height, dimensional stability are good, form final products with the coverlay that has mechanical protection and good electrical insulating property concurrently by compacting.Top layer and inner conductor two-sided, multilayer printed wiring board are realized being electrically connected of ectonexine circuit by metallization.

Along with high density flexible wiring board high speed development in recent years, traditional line manufacturing process is in the face of more challenge.Correspond to traditional circuit plate manufacture craft, the technology difficulty of high density flexible wiring board, complexity can be described as and be multiplied, and directly have influence on manufacturing.Present stage PCB industry is along with the development of electron trade is constantly advancing always, and the flexible circuit board of fine-line is on the increase, and has brought no small challenge meanwhile for FPC on off test aspect.

At present commonly used in the circuit on-off field tests of flexible PCB have electric on off test, two kinds of method of testings of flying probe.

Electric on off test is a kind of hand inspection mode.At first at the flexible PCB of needs test, make corresponding measurement jig, then measurement jig is installed to testing apparatus, golden finger, the pad needs tested by the test probe of measurement jig carry out on off test.Yet, when the line pitch of flexible PCB too small (during spacing≤0.2mm), because the size of conventionally test probe restriction and can't flexible PCB being tested needs to make littler unconventional test probe this moment and tests.Need more cost of manufacture and longer fabrication cycle yet make this unconventional test probe, and this unconventional test probe compares the test probe of routine, its serviceable life is shorter.

Summary of the invention

The circuit on-off detecting method that the purpose of this invention is to provide a kind of flexible PCB can effectively reduce the cost of manufacture and the fabrication cycle of measurement jig.

For achieving the above object, the invention provides a kind of detection method of circuit on-off of flexible PCB, this flexible PCB comprises at less some first golden fingers of the spacing on flexible PCB top, some second golden fingers that spacing in the flexible PCB bottom is bigger, is located at some pads and some connecting lines between first golden finger and second golden finger, these some connecting lines are connected between first golden finger and second golden finger, between first golden finger and the pad or between second golden finger and the pad, this method comprises the steps:

(1) flexible PCB is fixed on the on off test tool;

(2) conductive fabric is placed on some first golden fingers of flexible PCB to be measured;

(3), and then judge break-make situation between described first golden finger and all second golden fingers, the pad by the break-make situation between test probe testing conductive cloth and all second golden fingers, the pad.

As mentioned above, the break-make detection method of the present invention's flexible PCB utilizes conductive fabric to be placed on the enterprising disconnected test that works of first golden finger of flexible PCB, do not need to use the test probe of non-common specification, effectively reduce the cost of manufacture and the fabrication cycle of measurement jig, the serviceable life of having improved measurement jig.

Description of drawings

In Figure of description:

Fig. 1 is the synoptic diagram of flexible PCB.

Fig. 2 is the synoptic diagram that flexible PCB is positioned over measurement jig.

The description of reference numerals of assembly is as follows among the figure:

Measurement jig 100 flexible PCBs 200

First golden finger, 20 second golden fingers 21

Pad 22 connecting lines 23

Conductive fabric 300

Embodiment

By describing technology contents of the present invention, structural attitude in detail, being reached purpose and effect, below exemplify specific embodiment and cooperate the graphic detailed explanation of giving.

See also Fig. 1, adopt the flexible PCB 200 of circuit on-off detecting method of the present invention's flexible PCB to comprise to be positioned at flexible PCB 200 tops be arranged parallel to each other and some first golden fingers 20 that spacing is less and be positioned at flexible PCB 200 bottoms be arranged parallel to each other and some second golden finger, 21, the first golden fingers 20 that spacing is bigger and second golden finger 21 between be provided with some pads 22.Flexible PCB 200 further comprises some connecting lines 23, and these some connecting lines 23 are connected between first golden finger 20 and second golden finger 21, between first golden finger 20 and the pad 22 or between second golden finger 21 and the pad 22.

See also Fig. 2, flexible PCB 200 is installed with the centre at measurement jig 100.During test, conductive fabric 300 is placed on some first golden fingers 20 of flexible PCB 200, by the electric action of conductive fabric 300, with these a little first golden finger, 20 short circuits.

The circuit on-off detecting method of the present invention's flexible PCB comprises the steps:

(1) flexible PCB 200 is fixed on the on off test tool 100;

(2) conductive fabric 300 is placed on some first golden fingers 20 of flexible PCB to be measured 200;

(3) by the break-make situation between test probe (figure do not show) testing conductive cloth 300 and all second golden fingers 21, the pad 22, and then judge break-make situation between described first golden finger 20 and all second golden fingers 21, the pad 22, if there is the situation that opens circuit, then described tested flexible PCB 200 is a substandard product.

For the high density flexible circuit board, with respect to existing electric on off test, adopt the break-make detection method of the present invention's flexible PCB 200, promptly utilize conductive fabric 300 to be placed on first golden finger, the 20 enterprising disconnected tests that work of flexible PCB 200, do not need to use the test probe of non-common specification, effectively reduce the cost of manufacture and the fabrication cycle of measurement jig, the serviceable life of having improved measurement jig.

The above; only for the preferable specific embodiment of the present invention, but protection scope of the present invention is not limited thereto, and anyly is familiar with those skilled in the art in the technical scope that the present invention discloses; the variation that can expect easily or alternative all should be encompassed within protection scope of the present invention.Therefore, protection scope of the present invention should be as the criterion with the protection domain of claims.

Claims (1)

1. the circuit on-off detecting method of a flexible PCB, this flexible PCB comprises at less some first golden fingers of the spacing on flexible PCB top, some second golden fingers that spacing in the flexible PCB bottom is bigger, is located at some pads and some connecting lines between first golden finger and second golden finger, these some connecting lines are connected between first golden finger and second golden finger, between first golden finger and the pad or between second golden finger and the pad, it is characterized in that: this method comprises the steps:

(1) flexible PCB is fixed on the on off test tool;

(2) conductive fabric is placed on some first golden fingers of flexible PCB to be measured;

(3), and then judge break-make situation between described first golden finger and all second golden fingers, the pad by the break-make situation between test probe testing conductive cloth and all second golden fingers, the pad.

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