Abstract: A method and apparatus for facilitating interconnection of lead wires to an integrated circuit including the provision of an additional protective layer of insulation to the top of an integrated circuit chip or die and the provision of enlarged plated electrodes to the surface of the additional insulation to form enhanced bonding pads, such pads being electrically connected through the protective layers to the normal bonding pads of the integrated circuit device. The enhanced bonding pads are made of a soft conductive metal such that external wires to be attached thereto can be bonded to the pads using a thermal compression bonding technique.

Abstract: A method and apparatus for facilitating interconnection of antenna lead wires to an integrated circuit and encapsulating the assembly to form an improved miniature transponder device including the provision of an additional protective layer of insulation to the top of an integrated circuit chip or die and the provision of enlarged plated electrodes to the surface of the additional insulation to form enhanced bonding pads, such pads being electrically connected through the protective layers to the normal bonding pads of the integrated circuit device. The enhanced bonding pads are made of a soft conductive metal such that external wires to be attached thereto can be bonded to the pads using a thermal compression bonding technique, This invention also extends to a method of encapsulating a transponder in heat shrunk plastics material.

Abstract: A transponder system including a transponder and an interrogator having a transmission coil for producing a high-intensity electromagnetic field for inductively powering the transponder and two receiver coils for receiving a low-intensity electromagnetic field reradiated by the transponder. The transmission coil includes one or more conductive windings circumscribing a substantially polygonal volume of space. The receiver coils are diametrically disposed opposite one another within the volume space of the transmitter and are electrically connected to each other in a differential circuit relationship, the output of which is at a minimum when the two receiver coils receive approximately equal quantities of energy and is at a maximum when one of the receiver coils receives more electromagnetic energy from the transponder than the other receiver coil. The transponder uses a coil to derive both a power source and a clock pulse from the high-intensity field for powering and driving an identification circuit.

Abstract: A transponder system including a transponder and an interrogator having a transmission coil for producing a high-intensity electromagnetic field for inductively powering the transponder and two receiver coils for receiving a low-intensity electromagnetic field reradiated by the transponder. The transmission coil includes one or more conductive windings circumscribing a substantially polygonal volume of space. The receiver coils are diametrically disposed opposite one another within the volume space of the transmitter and are electrically connected to each other in a differential circuit relationship, the output of which is at a minimum when the two receiver coils receive approximately equal quantities of energy and is at a maximum when one of the receiver coils receives more electromagnetic energy from the transponder than the other receiver coil. The transponder uses a coil to derive both a power source and a clock pulse from the high-intensity field for powering and driving an identification circuit.

Abstract: A coil assembly for use in an inductively powered transponder including a primary coil and a secondary coil wrapped around the same coil forming ferrite rod. The primary coil's leads are left floating while the secondary coil's leads are connected to the integrated identification circuit of the transponder. There are approximately three times as many turns to the primary coil as there are turns to the secondary coil. The primary coil is configured to self resonate at the operating frequency of the identification circuit when brought within range of an interrogator's magnetic field, thereby creating a voltage across the primary coil having a high source impedance.

Abstract: An improved automated method for the manufacture of alternatively sized passive transponder devices is presented which utilizes a single leadframe design and manufacturing process, including automated coil winding and wire-to-lead termination. A specially designed leadframe is prepared, with augmented leads, and is coated with a thin layer of silver. One or more semiconductor chips are bonded to individual assembly sites on the leadframe, after which the lead-die assembly is encapsulated by transfer molding. The cap and leads are singulated, and a bobbin is attached to the leads, which extend laterally from each individual molded cap. In an automated process, a conductive wire is attached to a first of the protruding leads, fly-wound around the bobbin core, and terminated by connection to a second of the protruding leads.

Abstract: An improved automated method for the manufacture of small implantable passive transponder devices is presented in which semiconductor wafer die are bonded to a conductively coated tape leadframe. This tape, with die attached, is injected molded to form a cap around the leads and the attached die, such that the exposed portion of the leads extend laterally from the cap. A ferrite core is attached to the base of the cap, and a fine coil wire, dispensed from a specially designed applicator, is automatically bonded to one of the leads protruding from the cap body. The wire is subsequently wound around the ferrite core and terminated by automatic attachment to another of the protruding leads. The assembled device is thereafter encapsulated within a small glass housing.

Abstract: An electromagnetic transmission and detection apparatus comprising a transmission coil (20) for producing a high intensity electromagnetic field including one or more conductive windings (24) circumscribing a substantially polygonal volume of space having a central axis, and first and second receiver coils (22) disposed within the polygonal volume of space for receiving a low-intensity electromagnetic field transmitted from an external source. The receiver coils (22) are co-planar with the transmitter coil (20) and are disposed within the polygonal volume of the transmitter coil at positions which are polygonally, diametrical opposed to one another. The receiver coils (22) are electrically connected to each other in a differential circuit relationship such that the magnitude of electrical signals induced in the receiver coils (22) by uniform electromagnetic energy are substantially equal and opposite to one another.