JPS60132383A - Printed circuit board - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a printed wiring board on which heavy components are mounted.

BACKGROUND ART Conventionally, when a large number of electrodes are extracted from a printed wiring board of a panel display having a matrix structure and connected to electrodes of other printed wiring boards, a part of the electrodes at the connection part of the side board is used. Perform temporary soldering. In this case, since the electrodes at the connecting portions of both substrates are facing each other, it is impossible to directly heat the entire connecting portion.

Object The object of the present invention is to meet the above-mentioned technical objectives. 4; To provide a printed wiring board in which both the printed wiring boards can be easily temporarily fixed by soldering.

In order to fully drive a display device in which display elements having an XY matrix electrode structure such as the thin film EL element of the embodiment are mounted, the same number of drive circuits are required for all the electrodes required for driving. E
L is an abbreviation for electroluminescence. For example, in a display device having 240 lines of electrodes on the X side and 320 lines on the Y side, a total of 560 drive circuits are required.

Therefore, in order to process such a large number of electrodes and drive circuits, various improved techniques have been proposed regarding drive circuits and mounting methods.

FIG. 1 is a block diagram of peripheral circuits of a thin film EL display device showing one example of this. A detailed explanation will be given below based on FIG. When driving a display element 1 having IJ electrodes, as shown in FIG. 6, 7, memory circuit 5, gate circuit 4, etc.) are required. Furthermore, the number of connection lines between logic circuits and the number of connection lines between logic circuits and I/J box electrodes are enormous. On the other hand, only a few wires are needed to send signals from the data circuits 8 and 9 and the control circuit 10 to the logic circuit, and by forming the logic on a substrate such as ceramic, the number of connection lines between the logic can be reduced within the integrated circuit. can be processed. Also, in the electrode drive circuit part, the second
As shown in the figure, the drain of the high voltage drive transistor 11 and the cathode of the diode 12 are connected and the intersection is output as a high voltage output.
When using two chips, the high-voltage pivoting integrated circuit 13 containing the high-voltage driving diode array 14, and the high-voltage drive diode array 14, intersection points inevitably occur, so several sets of these two chips are placed on a small board. A hybrid type has been proposed in which wiring is processed within the overlying board (Japanese Patent Application No. 51-8742).
No. 0, see Japanese Patent Application No. 51-106518). In this proposal, complex circuit systems are processed on the same board,
This board is attached to a motherboard such as a flexible board to obtain output lines in one-to-one correspondence with the matrix electrodes with little human effort.

FIG. 2 is an enlarged electrical circuit diagram showing an embodiment of the driving line of the XY matrix electrode in FIG. 2;

A high voltage drive transistor 11 and a high voltage drive diode 12 are connected to one electrode line group of the X-Y matrix electrodes arranged in the thin film EL display element 1, one for each line. .

Therefore, the number of high-voltage driving diodes 12 required is the same as the number of electrode lines, and a transistor array 13 in which transistors 11 are integrated and a diode array 14 in which diodes 12 are integrated are formed. The transistors 11 and diodes 12 are connected in a one-to-one correspondence, and are connected one-to-one to each electrode line at the connection point.

Each transistor 11 is a circuit element that selectively applies a driving voltage to each electrode line, and each diode 12 is a circuit element that selectively applies a driving voltage to each electrode line, and each diode 12 applies a driving voltage to each electrode line of a display device driven at a high voltage, such as a thin film EL transistor. It has a protective effect against
This is a circuit element required to prevent overcurrent. Therefore, the transistor 11 and the diode 12 are arranged in a one-to-one correspondence with each other and with respect to the electrode lines.

FIG. 3 is a sectional view of the mounting part of the circuit board on which all circuit elements are mounted.

Conductive wiring 22 is formed on the screen of a flexible substrate 21 made of an organic film or the like, and electrical continuity is obtained between the conductive wiring 22 on both the front and back surfaces through through holes 23 formed in the substrate 21. This portion is extended and connected to the electrode line of the XY matrix electrode.

On the conductor wiring 22 on one side of the substrate 21 is mounted a multiplier circuit for driving a driver, i.e., a transistor array 13, in which a predetermined number of transistors 11 shown in FIG. A diode package 25 comprising a diode array 14 in which a predetermined number of diodes 12 are similarly integrated is mounted on the diode package 22 . The transistor package 24 and the diode package 25 are resin-molded so that their external shapes are substantially the same, and are connected to the conductor wiring 22 at the same position from both the front and back directions using left and right lead terminals. This connection is performed by solder reflow or the like. Note that the through holes 23 are formed at inner positions of the left and right lead terminals in consideration of space factor gain. The leads of the transistor package 24 and diode package 25 are connected between conductors a22i.
They are connected to a plurality of electrode lines of the same number through each other.

The number of connected electrode lines is determined by the number of circuit elements integrated in each package 24, 25, and the number of packages 24, 25 mounted on the substrate 21 is determined by the total number of electrode lines.

The transistor packages 24 and diode packages 25 mounted on both the front and back surfaces of the substrate 21 are arranged symmetrically on the front and back, and can be arranged on the substrate 21 at a uniform pitch.

FIG. 4 is a plan view of a narrow connecting portion of a printed wiring board according to an embodiment of the present invention. When the printed wiring board 33 in FIG. 4(a) and another printed wiring board 35 on which the same pattern is formed are fully overlapped and connected, the pattern 31 on the surface 38 of the printed wiring board 33 and the pattern 36 on the printed wiring board 35 Perform temporary soldering on the part. In order to facilitate such temporary soldering, lands 3 are provided around the through holes 34 on the back side 39 of the printed wiring board 33, as shown in FIG. 4(C).
7 is provided. When soldering between the pattern 31 of the printed wiring board 33 and the pattern 36 of the printed wiring board 35, if the heater is brought into full contact with the land 37 shown in FIG. 4(c), the heat from the heater will be transferred onto the pattern 34. To quickly and reliably melt solder plating and perform soldering. Like this +c 1. Printed wiring board 33 and printed wiring board 35
are temporarily soldered.

After that, the patterns 32 and 39 of the printed wiring board 33 and the printed wiring board 35 are soldered and connected with resin.

Such a printed wiring board is effective for temporary soldering when connecting a circuit with many circuit terminals as shown in FIG.

Effects As described above, according to the present invention, by providing a land around the through-hole on the connection portion side of a double-sided printed wiring board, temporary soldering to the connection portion of another printed wiring board can be performed quickly and reliably. I can do it.

Further, the time required for connecting the circuit boards can also be shortened.

[Brief explanation of drawings]

Fig. 1 is a block diagram of the peripheral circuit of a thin film electroluminescent display device, Fig. 2 is a fully enlarged electrical and electrical circuit diagram showing an example of the drive line of the X-Y matrix electrode, and Fig. 3 is the circuit. A cross-sectional view of the main parts of a circuit board equipped with an element,
FIG. 4 is a plan view of the vicinity of the connection portion of the printed wiring board 33 according to an embodiment of the present invention. 31.36... Pattern, 33.35... Printed wiring board, 34... Through hole, 37... Land, 38
...Printed wiring board 330 surface, 39...Printed wiring board 33 back surface Agent Patent attorney Kei Nishi-1i No. 4 (b) ((c) Written amendment to oral proceedings Patent application 1982-24122-9 2. Name of the invention Printed wiring board 3. Relationship with the case of the person making the amendment Applicant's address and name (504) Spontaneous amendment by the representative of Sharp Corporation 6. Detailed description of the invention in the specification to be amended 7. Contents of the amendment (1) Lines 13 to 14 on page 7 of the specification are corrected as follows. Dissolve the plating quickly and reliably. (2) In the 18th line of page 7 of the specification, [and] is corrected to ``or.'' (3) The 6th line of page 8 of the specification is as follows: Correct to

Claims (1)

[Claims] One side of the double-sided printed wiring board having a double-sided wiring pattern is bonded to the other side of the double-sided printed wiring board in order to conduct heat conduction when fully overlapping solder connection is made with the pattern of the connection part of the other printed wiring board. A printed wiring board characterized in that a land is provided around a through hole on one side.