FR3022101A1 - PRINTED CIRCUIT BOARD FOR WIRING ELECTRONIC CIRCUITS. - Google Patents

Abstract

The present invention relates to a printed circuit board for wiring electronic circuits, of the type consisting of a plate (20) of electrically insulating material on at least one surface of which are printed conductive pads (21 and 22) arranged in a matrix . According to the present invention, said card is characterized in that the pellets (21) of the pellet group or groups which are aligned with each other in a first direction are electrically interconnected by a conductive line (23) extending in the first direction. direction and in that the pellets (22) of the or groups of pellets aligned with each other in a second direction different from the first direction, different from the pellets (22) electrically connected by the lines 23 parallel to the first direction, are electrically connected between them by conductive lines (24) extending in said second direction, without being in contact with the pellets (22) or with the conductive lines (23). The present invention also relates to a system for testing electronic components using at least one printed circuit board according to the invention as a configuration card of the test system.

Description

The present invention relates to a printed circuit board for the wiring of electronic circuits as well as an electronic component testing system using at least one such printed circuit board as a configuration board of the test system.

In FIG. 1, there is shown an embodiment of a printed circuit board for wiring electronic circuits according to the state of the art. It consists of a plate 10 of electrically insulating material on a surface of which are printed conductive pads 11, here square. The plate 10 is pierced right through with holes 12 in the center of each pellet 11. It is thus possible to mount electronic components, such as the component 13, so that each of their lugs 14 passes through a hole 12 of a pellet 11 and is welded to it. In the same way, electrical wires, such as the wire 15, can be welded between two adjacent pellets 11 or, on the contrary, remote. It will be understood that it is then possible to mount and solder all the electronic components of an electronic circuit and thus to carry out the wiring of this electronic circuit. The example shown in FIG. 1 is single-sided or single-layer but more complex multi-layer circuit boards are also known. Such printed circuit boards are known as test plates because they make it possible to rapidly produce an electronic circuit for testing its electrical characteristics and this, before its final embodiment where the electronic components are mounted on a circuit board with tracks. drawn optimally. Also known is US-A-5 387 861 which discloses an electronic component testing system essentially consisting of a motherboard on which is mounted a plurality of electronic component holders, such as an integrated circuit. It also comprises, for each electronic component support, connectors each connection element of which is, firstly, electrically connected to a tab of said electronic component support and, secondly, is capable of being connected to a connector. connecting element of a complementary connector of a configuration plate. Each configuration plate is of the same type as that shown in FIG. 1, further incorporating connections to the complementary connector. Such a test system is used to test electronic components powered and receiving various signals, including clocking or timing signals, under relatively high temperature conditions obtained in appropriate ovens. Such systems are known as "burn-in systems" in English terminology. For a series of electronic components of a first type, the configuration cards are all wired in a first manner so that each electronic component is powered and can receive and transmit signals correctly. For another series of a second type, new configuration cards are made to be all wired in a second manner adapted to the components of the second series.

The main disadvantage of printed circuit boards for wiring electronic circuits according to the state of the art as just described is that they often require the use of electrical wires (ie the tabs 14). a component, or wires such as wire 15) to provide the connections necessary for the realization of the electronic circuit. These electrical wires can, if they are numerous, cross each other and form bundles of threads that are very difficult to locate. The electronic circuit can become rather quickly rough. In addition, the use of electrical wires and electronic components with electrical wires implies that these elements are mounted and welded manually. This is particularly disadvantageous, especially in the case of burn-in systems, where a new series of several configuration cards must be made and where automatic wiring of the electronic circuit by means of a machine would be advantageous in terms of time spent on the machine. realization of the series and in terms of reliability. The object of the present invention is to provide a printed circuit board for the wiring of electronic circuits that does not use electrical son to achieve the interconnection of the electronic components of said electronic circuits. Thus, it is possible to carry out wiring of an electronic circuit automatically by means of a suitable machine. To do this, a printed circuit board for wiring electronic circuits according to the present invention is of the type consisting of a plate of electrically insulating material on at least one surface of which are printed conductive pads arranged in a two-dimensional network. . A card according to the invention is characterized in that the pellets of or groups of pellets which are aligned with each other in a first direction are electrically interconnected by a conductive line extending in the first direction and in that the pellets the group or groups of pads aligned with each other in a second direction perpendicular to the first direction, different from the pads electrically connected by the lines parallel to the first direction, are electrically interconnected by conductive lines extending in said second direction, without being in contact with the pellets or the conductive lines. According to another advantageous characteristic of the invention, the pellets connected to a conductor line and the pellets aligned with said pellets are alternated in the second direction.

According to another advantageous characteristic of the invention, said card is at least two printed layers, the pellets as well as the conductive lines extending in the first direction are printed on one of said two layers, the conductive lines extending in the second direction being printed on another layer, the pellets being connected to the conductive lines of said other layer.

According to another advantageous characteristic of the invention, the pellets are connected to the conductive lines of said other layer via metallized holes. According to another advantageous characteristic of the invention, a printed circuit board comprises at least one printed layer serving as a ground plane.

According to another advantageous characteristic of the invention, it comprises another printed layer almost identical to the layer on which the pellets are printed as well as the conductive lines extending in the first direction. According to another advantageous characteristic of the invention, it comprises connectors for connecting other cards or measuring devices.

According to another advantageous characteristic of the invention, it comprises at least one drawing making it possible to weld one or more active components. The present invention also relates to a system for testing electronic components of the type comprising a motherboard on which a plurality of electronic component supports are mounted, each support being intended to receive an electronic component, such as an integrated circuit to be tested in adverse temperature and humidity conditions and configuration boards mounted via appropriate connectors. According to the present invention, such a system is characterized in that each configuration card is a printed circuit board as just described.

According to another advantageous characteristic of the invention, said motherboard comprises printed conductive lines (which provide the connection between connection terminals of a part of the motherboard and pads of each connector and printed conductive lines which provide the electrical connection of the tabs of the component supports to respectively other pads of said connectors). The characteristics of the invention mentioned below, as well as others, will appear more clearly on reading the following description of exemplary embodiments, said description being given in relation to the attached drawings, among which: FIG. 1 is a perspective view of an exemplary embodiment of a printed circuit board for wiring electronic circuits according to the state of the art, FIG. 2 is a perspective view of an exemplary embodiment of a printed circuit board for the wiring of electronic circuits according to the invention, and FIG. 2a is a top view of a pair of pellets of a printed circuit board according to the present invention, Figs. 3a-3c are views of the layers of a printed circuit board for wiring electronic circuits according to an advantageous embodiment of the present invention, Figs. 4a and 4b are views of an electronic component testing system using printed circuit boards according to the present invention as configuration boards, and Figs. 5a to 5c are three-layer views of the same embodiment of a printed circuit board according to the present invention which can be used as a configuration board of a system according to Figs. 4a and 4b.

The printed circuit board for the electronic circuit wiring shown in FIG. 2 consists of a plate 20 of electrically insulating material, on a surface of which are printed pairs of conductive pads 21 and 22. In FIG. 2, the pairs of pellets 21 and 22 are arranged in a single group forming a matrix (here 3 x 4 pairs of pellets 21 and 22). In general, the present invention is applicable to printed circuit boards which would include several groups of pairs of pellets, the pairs of each group being arranged in a matrix. The arrangement of the pairs of pellets 21 and 22 in the matrix is such that the pellets 21 of the or each pair of pellet pairs which are aligned with each other in a first direction are electrically interconnected by a conductive line 23 (not necessarily rectilinear, in this case broken so as not to come into contact with the pellets 22) which extends in this first direction. The pellets 22 of the or each group of pellets which are aligned with each other in a second direction different from the first direction (for example perpendicular to the first direction), are electrically interconnected by conductive lines 24 extending in said second direction. direction, without being in contact with the pellets 21 nor with the conductive lines 23. In addition, in the first direction, because they are in pairs, the pellets 21 and the pellets 22 are alternated. Thus, by moving in FIG. 2, from left to right in the first direction, there is successively a pellet 21, a pellet 22 of the same pair as the preceding pellet 21, again a pellet 21 and a pellet 22, etc. In FIG. 2a, there is shown, from above, a pair of pellets 21 and 22. Each pad 21, 22 consists of a pad 210, 220, in this case a square pad, adjacent to another pad 211, 221, in this case circular, drilled in the center of a hole 212, 222 provided to receive a tab of a component or a wire. In the exemplary embodiment shown, if one considers a pair of two pellets 21 and 22, the two pierced pads 211 and 221 abut the non-pierced pads 210 and 220 at their farthest sides. The latter comprise protrusions 213 and 223, in this case rectangular, at their sides facing each other. Thus, the pellets 21 and 22 of the same pair of pellets are close to one another so as to be able to deposit on this pellet 21 and this pellet 22 a weld spot 26 (in particular on the protuberances 213 and 223). , which has the effect of short-circuiting said two pads and thus connect together a line 23 in the first direction and a line 24 (drawn in dotted line) in the second direction (in this case the lowest line 23 and the second line 24 from the left in Fig. 2). It is also possible to weld a surface component component 27, called CMS, between a chip 21 and a chip 22 of the same pair of pellets. The size of the pellets 21 and 22 associated with the protuberances 213 and 223 offers the possibility of welding CMS components of different dimensions. Thus, via said component 27, a line 23 is connected in the first direction and a line 24 in the second direction (in this case the highest line 23 and the rightmost line 24 in Fig. 2). .

Similarly, it is possible to weld components, such as the component 28 between a pellet 21 and a pellet 22 not necessarily of the same pair (the tabs 29 and 29 'of the component 28 are respectively housed in the holes 212 and 222 pellets 21 and 22 considered). These components 28 can be mounted flat as shown in FIG. 2, but also in ears. The printed circuit board of FIG. 2 is two printed layers. In general, a printed circuit board according to the invention comprises at least two layers. The pellets 21 and 22 as well as the conductive lines 23 are printed on one of the two layers, in this case the upper layer of the card 20. The conductive lines 24 are printed on another layer, in this case the lower layer of the card 20. The pellets 22 which are connected to a line 24 are via metallized holes 25, for example made of sleeves housed in the holes 222. A circuit board such as one just described can be used as a test plate, that is to say a printed circuit board on which the user temporarily cable an electronic circuit to be able to appreciate the feasibility and functionality of an electronic assembly which will then be done in a clean and definitive way. By means of the printed circuit board of the present invention, the realized electronic circuit is cleaner than that of the state of the art. FIGS. 3a to 3c are the printed circuit board drawings of a printed circuit board 300 for constituting such a test plate and according to one embodiment of the present invention. Fig. 3a represents the upper layer. There can be seen pellets 21 which are interconnected by conductive lines 23 extending in the horizontal direction of FIG. 3a and pellets 22 which in this FIG. 3a, seem not to be connected to each other (they are on another layer). In this FIG. 3a, there are two groups 301 and 302 of pairs of pellets 21 and 22. The horizontal lines 23 of the group 301 are respectively connected to integrated circuit pads 303 and to connector pads 305 of a connector (not shown) for possible connection to another circuit board, or other such as measuring devices, power supply, etc. Similarly, the horizontal lines 23 of the group 302 are respectively connected to integrated circuit pads 304 and connector pads 306 of a connector (not shown) for possible connection to another printed circuit board or the like. The integrated circuit pads 303 and 304 are provided to receive the tabs respectively on one side and the other of integrated circuits (not shown) whose housings are of the so-called DIP type. Another design of the integrated circuit pads 303 and 304 could be adapted to integrated circuits whose housings are of another type, for example of the SO type, etc. Each of the pads 22 of the pellet pair line 21 and 22 is connected to the connector pads 307, a connector (not shown) for possible connection to another circuit board or the like. Fig. 3b represents another layer than the upper layer. There can be seen conductive lines 24 (vertical lines in Fig. 3b) which connect together connected pads, through holes 222 metallized, pellets 22 of the upper layer. These conductive lines 24 are also connected to connector pads 308 for possible connection to another integrated circuit card or the like. It can also see the connector pads 305 and 306. The connectors 305 and 306 are advantageously double. While lines 23 connect the left connector pads 306 to the left integrated circuit pads 304 (see Fig. 3a), lines 23 'printed on a third layer shown in FIG. 3c, connect the right connector pads 306 to the integrated circuit pads 303. Similarly, while lines 23 connect the right connector pads 305 to the right integrated circuit pads 303 (see Fig. 3a, lines 23). , also printed on this third layer, connect the left 305 connector pads to the integrated circuit pads 304. This arrangement ensures continuity between the connector pads 305, the connector pads 306 and the integrated circuit pads. 303 and 304. Another possible application of a printed circuit board according to the present invention will now be described.This application relates to a system, of the "burn-in systems" type, for the testing of electronic components. 4a and 4b and essentially consists of a motherboard 30 on which is mounted a plurality of electronic component supports 31, each support 31 being intended to receive a electronic component, such as an integrated circuit (not shown), to be tested under adverse temperature and humidity conditions obtained in a suitable oven. Mounted via appropriate connectors 32, are also provided configuration cards 33, each associated, alone or with several (in this case in pairs), an electronic component support 31. According to the present invention, each card 33 is a printed circuit board according to the present invention.

In FIG. 4a, the configuration cards 33 are mounted perpendicularly to the motherboard 30 but, if the connectors 32 were different, they could also be mounted in a plane parallel to the plane of the motherboard 30, for example below the latter . The motherboard 30 has a portion 35 which is intended to be plugged into a connector (not shown) of a test machine so as to power the motherboard 30 in voltage and test signals, for example signals from clock or timing, and also be able to recover test result signals delivered by the components to be tested. The portion 35 of the motherboard 30 has connection terminals 36.

As can be seen in FIG. 4b, the motherboard 30 has printed conductive lines 34 (only a few lines are shown by way of example) which provide the electrical connection of the connection terminals 36 of the motherboard 30 respectively to the pads of the connectors 32, ensuring the electrical connection of the configuration cards 33 to the connection terminals 36 of the motherboard 30. It also comprises printed conductive lines 37 which provide the electrical connection of the tabs of the component supports 31 to respectively other pads of the connectors 32, thus providing the electrical connection between the legs of said supports 37 and the configuration cards 33. When a series of electronic components is to be tested, a lot of configuration cards 33 must be prepared by making, on each configuration card 33, the necessary soldering points 26 and positioning and welding the components 27 and 28 necessary to ensure the connections the functioning of the electronic components under test. The configuration board 33 provides the connections necessary to connect the lines 34 carrying the power signals, the clock and timing signals, the test result signals received or transmitted to the test machine (not shown) to the lines. 37 distributing these signals on the legs of the supports 31 and therefore the electronic components they house.

FIGS. 5a to 5c are the printed circuit board drawings of a printed circuit board for constituting a configuration board 33 according to an embodiment of the present invention. Fig. 5a represents the upper layer. There can be seen pellets 21 which are interconnected by conductive lines 23 extending in the horizontal direction of FIG. 5a and the pellets 22. The conductive lines 23 consist of perforated pads 211 which abut two neighboring unthreaded pads 210. The connector pads 320 for plugging into a connector 32 on the motherboard 30 are also recognized (see Figs 4a and 4b). Conductive lines 230 are connected to pins of the connector 320. FIG. 5b represents an intermediate layer between the upper layer and the lower layer in the insulating material plate 20. There can be seen the conductive lines 24 which extend in the direction perpendicular to the conductive lines 23, in this case in the vertical direction of FIG. 5b and which are connected, for example by metal holes 25 (see Fig. 2) to pellets 22. Finally, FIG. 5c represents the lower layer. It is generally of the same structure as the upper layer. The pads 22 of the lower row (in Fig. 5c) are connected to connector pads 320 by the lines 311. The advantage resulting from having two layers in the respective substantially identical drawings is that it is possible to mount components in parallel, for example a capacitor and a resistor to form an RC network and, more generally, this provides a greater flexibility of wiring design of a configuration card. According to the invention, other layers may be provided, in particular to form a ground plane allowing electromagnetic isolation of the layers between them.

Claims (10)

CLAIMS1) Printed circuit board for the wiring of electronic circuits, of the type consisting of a plate (20) of electrically insulating material on at least one surface of which are printed conductive pads (21 and 22) arranged in a matrix, characterized in that the pellets (21) of the pellet group or groups which are aligned with each other in a first direction are electrically interconnected by a conductive line (23) extending in the first direction and the pellets (22). the group or groups of pads aligned with each other in a second direction different from the first direction, different from the pads (22) electrically connected by the lines 23 parallel to the first direction, are electrically interconnected by conductive lines (24) extending in said second direction, without being in contact with either the pads (22) or the conductive lines (23). 2) printed circuit board according to claim 1, characterized in that the pellets (21 and 22) are arranged in pairs. 3) printed circuit board according to claim 1 or 2, characterized in that said card is at least two printed layers, the pellets (21 and 22) and the conductive lines (23) extending in the first direction are printed on one of said two layers, the conductive lines (24) extending in the second direction being printed on another layer, the pads (22) being connected to the conductive lines (24) of said other layer. 4) printed circuit board according to claim 3, characterized in that the pads (22) are connected to the conductive lines (24) of said other layer through metallized holes (25). 5) printed circuit board according to one of the preceding claims, characterized in that it comprises at least one printed layer serving as a ground plane. 6) printed circuit board according to one of the preceding claims, characterized in that it comprises another printed layer substantially identical to the layer on which are printed the pellets (21 and 22) and the conductive lines (23) s' extending in the first direction. 7) printed circuit board according to one of the preceding claims, characterized in that it comprises connectors (305, 306, 307, 308, 320) for connecting other cards or measuring devices. 8) printed circuit board according to one of the preceding claims, characterized in that it comprises at least one drawing (303, 304) for welding one or more active components. A system for testing electronic components of the type comprising a motherboard (30) on which a plurality of electronic component holders (31) is mounted, each support (31) being adapted to receive an electronic component, such as a integrated circuit to be tested under adverse temperature and humidity conditions and configuration boards (33) mounted via appropriate connectors (32), characterized in that each configuration board (33) is a circuit board printed matter according to one of the preceding claims. An electronic component testing system according to claim 9, characterized in that said motherboard (30) has printed conductive lines (34) which provide connection between connection terminals (36) of a portion (35) ) of the motherboard (30) and the pads of each connector (32) and printed conductive lines (37) which provide the electrical connection of the tabs of the component supports (31) to respectively other pads of said connectors (32). ).