Showing papers on "Flexible electronics published in 1998"

Handbook of Flexible Circuits

Abstract: Materials. Constructions. Design guidelines. Applications. Implementing flex. Manufacturing. Integrated features. Assembly. Polymer thick film flex. Performance and reliability.

Thin profile keypad with integrated LEDs

Abstract: A backlit keypad assembly includes a flexible film having a bottom surface having electrical circuits, typically referred to as flex circuits, thereon and a top surface having at least one, and preferably a plurality of keys defined thereon. Each backlit key includes a cavity on the underside thereof. In each cavity is a light emitting diode, preferably of bottom emitting type, attached to the flexible film and connected to the electrical circuits and a filler material which at least partially surrounds the light emitting diode. Associated with each key is a push-type switch below and in respective aligned relationship with the light emitting diodes which senses when the corresponding key is pressed down by a user. The light emitting diodes emit light directly through the flexible film without intervening layers such as light guides, thereby allowing the overall lighted keypad assembly to be thinner than with previous approaches. Such a keypad may be fabricated by directly attaching a plurality of bottom emitting light emitting diodes to the bottom side of the flexible film and connecting the light emitting diodes to the electrical circuits. Thereafter, the flexible film is vacuum formed so as to form a plurality of depressible keys on the top surface thereof and a corresponding plurality of cavities on the bottom surface thereof containing therein the light emitting diodes. The process continues by thereafter substantially filling the remainder of the cavities with a filler material which hardens upon curing and adheres to the bottom surface of the flexible film so as to form a flexible pad. The flexible pad is then typically placed in intimate contact with the printed circuit board and preferably mated thereto.

Iontophoretic drug delivery device and method of manufacturing the same

Abstract: An iontophoretic drug delivery device comprising a flexible reservoir sandwiched between a flexible printed circuit board and a pair of flexible electrodes. A rigid top cover is mounted on a spine on the reservoir by means of snap-fit connections. The rigid cover protects the device from damage while the flexible reservoir, circuit board and electrodes can conform to the skin of a subject. The configuration of the flexible elements allows the manufacturing process to be simplified considerably, resulting in a less expensive device with ease of fabrication.

Microelectric packages including flexible layers and flexible extensions, and liquid crystal display modules using the same

Abstract: The printed circuit board and tape carrier package of an LCD module are replaced with a microelectronic package that includes a substrate and a layer integrally formed on the substrate that is flexible relative to the substrate. The flexible layer includes at least one flexible extension that extends beyond the substrate. A plurality of conductive lines are included on the substrate that extend onto the flexible layer and extend along the flexible layer onto the at least one flexible extension. The conductive lines on the flexible extension are electrically connected to the data lines, the gate lines or both. Accordingly, tape carrier packages need not be used so that cost may be reduced. Moreover, separate operations to connect tape carrier packages to printed circuits boards may be eliminated, thereby improving reliability and/or cost of the device.

Display unit with flexible printed circuit board

Abstract: A display unit has a peripheral driver circuit mounted on a flat display substrate. The flat display substrate has on a surface thereof a plurality of scanning lines, a plurality of signal lines perpendicular to the scanning lines, and an input electrode connected to each of the scanning lines or the signal lines. The peripheral driver circuit has on a surface thereof a peripheral driver circuit for energizing the scanning lines or the signal lines, and input and output electrodes electrically connected to the peripheral driver circuit. The display unit also includes a driver circuit board having on a surface thereof a driver circuit for supplying a power supply voltage and transmitting a control signal to the peripheral driver circuit on the peripheral driver circuit substrate, and an output electrode electrically connected to the driver circuit. The input electrode of each of the scanning lines or the signal lines is electrically connected to the output electrode on the peripheral driver circuit substrate by a flexible printed circuit board. The input electrode on the peripheral driver circuit substrate is also electrically connected to the output electrode on the driver circuit board by the flexible printed circuit board. Since the electrodes on the boards are electrically connected by the flexible printed circuit board, it is not necessary to form bumps on the input and output electrodes of the peripheral driver circuit substrate.

Rigid/flex printed circuit board using angled prepreg

Abstract: A rigid flex printed circuit board wherein the flex section of said board comprises a basestock composite with edges, formed by laminating a conductive layer (56) to a flexible insulator layer (60), the conductor layer containing at least one conductive pathway (50) and the flexible insulator layer comprises fibers (48) dispersed in a matrix polymer. The fibers are oriented with respect to the conductive pathway so that the conductive pathway is substantially non-aligned with said fibers, substantially along an entirety of the conductive pathway in the flex section, so as to be flexible.

Connector for flexible conductive line components

Abstract: The present invention relates to a connector for flexible conductive line components suitable for a lower mounted profile in a device mounted on a printed circuit board. The connector comprises a metal plate, resilient spring portions, and connection terminal portions wherein the resilient portions, which allow the metal plate and individual contacts to accommodate and clamp a inserted flexible printed circuit parallel with respect to the printed circuit board, are disposed such that the lengthwise spring extension thereof lies in the parallel direction, leaving the height unaffected. The metal plate further comprises a substantially U-shaped transverse cross section which affords both a low mounting profile and a stable connection that experiences minimal bending.

Flexible printed circuit and connected printed circuit structure

Abstract: A flexible printed circuit having wiring patterns printed on a flexible resin film, comprising a narrow flexible area having first wiring patterns and constituting a flexible wiring part and a broad connection area adapted to be adhered to a main board and having second wiring patterns connected to the first wiring patterns and adapted to be electrically connected to wiring patterns on the main board. The second wiring patterns serve to electrically connect the first wiring patterns of the flexible wiring part to the wiring patterns on the main board. Also included is a conductive adhesion surface formed on the broad connection area along a side of the main board, having a width larger than a width of the first wiring patterns, and extending from an inside of a region to an outside thereof. The region is defined in the broad connection area by extending a boundary of the flexible area into the broad connection area. A flexible printed circuit can be provided which has a high peel-off resistance to an applied stress.

Ultrasonic probe with disconnectable transducer

Abstract: An ultrasonic transducer probe that provides a connector for quickly, easily, and reliably connecting and disconnecting the transducer electrical connections in such a manner that the connection is removable. In a preferred embodiment of the present invention, the connector provides means for receiving one end of a flex circuit that is attached at its other end to a multi-element transducer located at the distal end of a probe. The flex circuit is oriented and aligned in the connector with a separate flex circuit in such a manner that compression of the connector sections creates an electrical connection between the flex circuits. Since the connector is solderless, the flex circuits may be removed and replaced without damage to the flex circuits or flex circuit conductors.

Structure and method of mounting driver IC using anisotropic conductive film in liquid crystal display device

Abstract: A structure and method of mounting a driver IC using an anisotropic conductive film (ACF) in a liquid crystal display device is disclosed. ACFs are used in bonding a FPC (Flexible Printed Circuit) and in a COG (Chip on Glass) process at the same time. A film according to the present invention comprises a support film, a COG ACF adhered on one portion of the support film and a FPC ACF adhered on the other portion of the support film. Using the film disclosed in the present invention, the manufacturing process of the LCD panel becomes simpler and easier.

Method of manufacturing a circuit assembly from two or more layers of flexible film

Abstract: A method of manufacturing an electronic circuit assembly that includes a number of electrically interconnected flexible films, each flexible film having a flexible electrical wiring circuit. The electrical wiring circuits are interconnected between film layers and the film layers are adhered to a molded backing structure. A first flexible film is formed with a pattern of flexible electrical wiring circuits created on at least one surface thereof. The first flexible film has a passage that provides an electrical connection through the flexible film. A second flexible film is formed with a pattern of flexible electrical wiring circuits created on a least one surface thereof. The second flexible film has an electrical interconnect feature that connects with the electrical passage on the first film and electrically connects the first film with the second film. The first flexible film is overlaid juxtaposed the second flexible film so that the passage is aligned adjacent the electrical interconnect feature. The first and second flexible films are placed within an open mold. The mold is closed and a plastic material is injected within the mold adjacent at least one surface of the first and second flexible films. The molten plastic adheres to the first and second flexible films and forms an integral backing structure. The backing structure and first and second flexible films together form the circuit assembly.

Flexible printed wiring board, flexible printed circuit board, and their manufacture

Abstract: PROBLEM TO BE SOLVED: To provide a flexible printed circuit board and a flexible wiring board which can prevent the breakage of electronic parts by bending and the separation or disconnection of junctions, and methods for manufacturing the boards. SOLUTION: A flexible printed circuit board 1 is provided with a flexible resin film base 2, a circuit pattern 3 formed by etching or stamping conductive foil provided to the surface of the film base 2, electronic parts including a semiconductor chip 5 mounted on the circuit pattern 3 and bonded to the pattern 3, for example, through a BGA, a sealant 7 which seals the mounting and joining sections, and a plurality of relaxation holes 4 which are formed through a flexible printed wiring board in the periphery of the semiconductor chip 5.

Flexible printed circuit board unit having electronic parts mounted thereon

Abstract: A flexible printed circuit unit includes a flexible printed circuit board having one or more electronic parts mounted on a front surface thereof. A reverse side reinforcing plate is provided at a location of the reverse side of the flexible printed circuit board corresponding to a region in which the electronic parts are mounted. An upper reinforcing structure is provided on the front surface of the flexible printed circuit board for covering at least one of the electronic parts.

Improved iontophoretic drug delivery device and method of manufacturing the same

Abstract: This invention is an iontophoretic drug delivery device comprising a flexible reservoir (16) sandwiched between a flexible printed circuit board (12) and a pair of flexible electrodes (20, 21). A rigid top cover is mounted on a spine on the reservoir by means of snap-fit connections. The rigid cover protects the device from damage while the flexible reservoir, circuit board and electrodes can conform to the skin of a subject. The configuration of the flexible elements allows the manufacturing process to be simplified considerably, resulting in a less expensive device with ease of fabrication.

Positioning structure of a flexible printed circuit for a pick-up used in a disc drive and a pick-up assembly used in a disc drive

Abstract: A positioning structure of a flexible printed circuit for a pick-up used in a disc drive is disclosed. The structure comprises a turntable driven by a motor for supporting a disc thereon, a pick-up movable in a radial direction of the disc for reproducing information recorded on the disc to be supported on the turntable, a chassis provided with the turntable and the pick-up and having an opening and positioning members provided at or near the opening, a printed circuit board arranged below the chassis and provided with electrical circuits for inputting and outputting electrical signals to and from the pick-up, and a flexing printed circuit for connecting the pick-up to the printed circuit board through the opening of the chassis, wherein the flexible printed circuit is formed with engaging members to be engaged with the positioning members, respectively. This structure is capable of positioning the flexible printed circuit with respect to the chassis easily and reliably.

Printed circuit board to flexible printed circuit connection system

Abstract: A connection system requiring little or no force to mechanically and electrically connect a printed circuit board to a flexible printed circuit. The connection system includes a flat and rigid carrier having an upper surface upon which is affixed a flexible printed circuit having an electrically conductive raised area in the form of a plurality of raised dots. At the upper surface, the carrier has a groove formed therein, wherein the raised dots are located in the groove. An elastomeric insert is situated in the groove in abutting relation to the flexible printed circuit behind the raised dots. A rigid printed circuit board has an electrically conductive area in the form of a plurality of pads. The printed circuit board is inserted into the groove, whereupon the elastomer resiliently compresses so as to press the plurality of raised dots into tight electrical contact with the plurality of pads. In a first preferred embodiment the printed circuit board is inserted vertically with slight force. In a second preferred embodiment, the printed circuit board is inserted at an acute angle with zero insertion force and then rotated to the vertical.

COG type liquid crystal panel and fabrication method thereof having first and second conductive bumps in different planes

Abstract: A liquid crystal panel incorporating a chips on glass (COG) system has a significantly increased field area and greatly reduced glass substrate size because driving integrated circuit chips for applying signals to electrode pads connected to pixels and flexible printed circuit films for applying electrical signals to the driving integrated circuit chips are overlappedly mounted on a lower glass substrate.

Flexible printed circuit with damping sheet and disk device using the same

Abstract: PROBLEM TO BE SOLVED: To obtain a disk device in which the vibration of a flexible printed circuit(FPC) can be suppressed by a damping sheet, which realizes the FPC having the long bending life of a conductor pattern and which suppresses the vibration of an actuator SOLUTION: In this disk device, a cover film 15 which is bonded, by a second adhesive 14, to the surface of a conductor pattern 13 which is bonded, by a first adhesive 12, to one face of a base film 11 is used, and an FPC which is bonded to the other face of the base film 11 or to the surface of the cover film 15 and which is provided with a damping sheet 17 is used The thickness of the base film 11, that of the cover film 15 and that of the damping sheet 17 are selected in such a way that the conductor pattern 13 is situated in the center of their thickness direction Thereby, a neutral face N is situated at the inside of the conductor pattern 13

Bump formation method

Abstract: A method for forming bumps in an LSI package in which: semiconductor chips are mounted onto a flexible printed circuit board; electrically conductive balls are temporarily fixed by using a fixing liquid including one selected from a group including flux, solder paste and an adhesive containing an electrically conductive agent, onto pads which are provided on the flexible printed circuit board so as to be electrically connected to the semiconductor chips; the flexible printed circuit board having the electrically conductive balls temporarily fixed thereto is wound up onto a reel; the flexible printed circuit board having the electrically conductive balls temporarily fixed thereto is fed out from the reel and heated to thereby form bumps thereon; and the flexible printed circuit board having the bumps formed thereon is wound up onto another reel; and the flexible printed circuit board is cleansed and trimmed to thereby form LSI packages.

Tamper-proof electrical apparatus

Abstract: The protected electrical device (1) is fully enclosed by a flexible printed circuit board (3), provided with a network of electrical linked conductor paths (17) coupled to a monitoring circuit (2), for detecting mechanical damage to the network. The outer surface of the flexible printed circuit board (3) is enclosed by a covering (19) which cannot be removed without damaging the conductor path network.

Display apparatus for notebook computer

Abstract: A display apparatus that has a light and thin panel module to be capable of preventing noise. In the display apparatus, the row and source drivers for driving the display panel is controlled by the timing control board which is positioned on main printed circuit board of the notebook computer body. The timing control board is connected with the row and source drivers by the flexible printed circuit film.

Design and construction of a new generation of flexible ultrasonic transducer arrays

Abstract: With ultrasonic arrays designed for conventional non-destructive evaluation of non-planar surfaces, significant difficulties are encountered. Typical attempts to solve this problem include the use of a 'shoe'to fit the surface, or an area machined flat for permanent attachment. These, however create additional problems for reliable inspection. An ideal solution would be a small thin transducer conformable to curved surfaces, without necessarily requiring permanent bonding to the test subject. This paper details the design and construction of flexible ultrasonic array transducer which satisfies these requirements. The device we report consists of an active ceramic/polymer platelet configuration, with the platelet aspect ratio greater than five, and a flexible printed circuit board used to support the structure and define the electrodes. Linear systems and finite element (ANSYS) computer modelling have been used to determine material selection and constructional parameters, and a scanning laser vibrometer to confirm the thickness mode behaviour predicted by the finite element work. The operating frequencies of the devices range from 6 to 8 MHz. Pulse-echo mode has been used to detect a variety of flaws in curved test-pieces with the arrays. The devices were attached to test specimens using only Velcro straps, and coupled with a standard couplant gel. Images of the defects are presented to indicate the high-quality data which can be produced, clearly demonstrating the viability of the economical flexible transducer design.

Fold flex electrical connector

Abstract: An electrical connector includes a molded plastic connector body, a flexible printed circuit, a plurality of plastic cable trays, an elastomeric pad and a molded plastic cap. The flexible printed circuit includes a main section and two side sections that are attached to respective longitudinal sides of the main section by flexible webs. A plastic cable tray is attached at a rearward end of each section. Thin copper conductors are arrayed in the flexible printed circuit so that each copper conductor is attached to a raised feature pressure contact in a forward contact portion of the main section of the flexible printed circuit at one end and disposed in a cable channel of one of the plastic cable trays at the other end. Electric cable ends are secured in the cable channels and electrically connected to exposed contact pads of the copper conductors. A first side section is folded over the main section with its cable tray stacked on the top of the cable tray of the main section. The second side section is folded over the first side section with its plastic tray stacked on top of the plastic tray of the first side section. The folded subassembly is disposed in the connector body with the forward contact portion of the main section folded over the elastomeric pad which lies against the front wall of the connector body. The plastic cap is attached to the front of the connector body with the raised feature pressure contacts exposed in an opening in the face of the cap.

Fabrication process for flex circuit applications

Abstract: The invention provides a process for fabricating a flexible printed circuit with at least one etched or plated feature on each major surface of said flexible circuit, comprising the steps of providing an input material (1) with two major surfaces, including a dielectric substrate (10) and at least one conductive base layer (11), laminating a photoresist (16) with a cover sheet (14) onto at least one major surface of the input material (1), and printing an image (18) onto the cover sheet (14) or removing the cover sheet (14) and printing the image (18) onto the photoresist (16) directly.

Flexible circuit board fitting structure and recording copying device of using the same

Abstract: Disclosed is an inexpensive structure for mounting a flexible printed circuit board to a hard circuit board without using a connector. The terminal section of the flexible printed circuit board is mounted to a holding member, which is secured to the hard circuit board to electrically connect the wiring pattern of the terminal section to the electric circuit of the hard circuit board, whereby it is possible to mount the flexible printed circuit board to the hard circuit board without using an expensive connector, thereby achieving an improvement in terms of cost and operability.

Manufacture of polyimide cover lay film

Abstract: PROBLEM TO BE SOLVED: To manufacture a cover lay film for a flexible printed circuit board with small curl and good adhesion by heating or dampening a mold releasing material just before stacking the mold releasing material, thereby adjusting the moisture content of the mold releasing material within the specified range. SOLUTION: A thermosetting adhesive such as epoxy resin, phenol butyral resin, epoxy-NBR resin, or the like is applied by a roll coater on one side of a polyimide film just before stacking a mold releasing material, and a solvent is evaporated and removed at 50-150 deg.C by an in-line drier so as to half harden the thermosetting adhesive, and then the mold releasing material where the moisture content is adjusted to 2-4wt.% by a heated roll is stacked. Hereby, a cover lay film for a printed circuit board with small curl and good adhesion can be manufactured, and the productivity and yield can be improved.

Flexible printed circuit board

Abstract: PROBLEM TO BE SOLVED: To dissolve troubles, such as damage to mounting components and the injury of an operator, by a method in which the edge part of a flexible printed wiring board is covered with an extension part, which is extended from the edge part of a reinforcing plate. SOLUTION: The width of a mounting region of a flexible printed wiring board 12 is formed in a width roughly equal to that of a reinforcing plate 14 and both side edges of the board 12 are made to coincide with the side edges of the plate 14. The point of the board 2 is extended by a prescribed length from the edge part of the plate 14 and an extension part 22 is formed. In a mounting work, an operator holds the edge part of the plate 14 for a flexible printed circuit board 10 with his finger to make the connection of stacking connectors 15 with the board 12. The operator holes the edge part of the plate 14 via the extension part 22 of the board 12 and his finger never comes into contact directly with the edge part of the plate 14. Thereby, troubles due to the plate 14 or the leads of an electronic component, such as damage to the mounting components and the injury of the operator, can be dissolved.

Flexible printed board

Abstract: PROBLEM TO BE SOLVED: To provide an FPC(flexible printed circuit) which can suppress cross- talk and unnecessary radiation especially at a bent part and a wound part and obtain flexible and durable performance. SOLUTION: This FPC has a three-layer structure consisting of a wiring layer 11, a surface layer 12 and a rear layer 13. The surface layer 12 and the rear layer 13 have lattice-shaped shielding patterns so as to hold the wiring layer 11 between them. The copper foil removed parts 14 and 20 of the shielding patterns of the surface layer 12 and the rear layer 13 are shifted relatively to each other so as not to overlap each other. The copper foil parts 15 and 19 of shielding patterns of the surface layer 12 and the rear layer 13 and the GND pattern of the wiring layer 11 are connected to each other with a plurality of through-holes 16 and 21 and a signal copper foil 18 is totally surrounded by a ground potential (GND). COPYRIGHT: (C)2000,JPO

Connector for flexible printed circuit board

Abstract: PROBLEM TO BE SOLVED: To provide a connector for a flexible printed circuit board capable of working well with an existing automatic wiring line easily and preventing an FPC mounted in an FPC connector from falling out therefrom. SOLUTION: A connector 10 for a flexible printed circuit board has a housing 15, and between the housing 15 and board 11, a latch means 30 is interposed to cause them 15 and 11 to be in mutual engagement when a slider 17 is moved horizontally and inserted into a board insert hole 16. COPYRIGHT: (C)2000,JPO

Glass connector and fabricating method thereof

Abstract: A glass connector that is adapted to simplify a flexible printed circuit film as well as to eliminate the delay in electrical signals. In the glass connector, a low resistance metal wiring is formed on the surface of a glass plate. A plurality of connecting bumps extending upwardly is provided on the metal wiring.