Abstract: Method and apparatus for spatially optimizing the arrangement of surface mount pads on a ball grid array package. An array containing T surface mount pads with a diameter less than or equal to 0.4 millimeter is arranged in an array of rows and columns less than or equal to 0.5 millimeters center-to-center. The array of pads is subdivided into N groups of pads respectively numbered Gx (for X from 1 to N), each group containing Px pads (for X from 1 to N). Each pad in each group is located so as to maximize the number of empty spaces Sz that are adjacent to each pad, where Sz=(Gx?1). The number of fanout possibilities for each group (Px*Sz) is calculated, and then the total number of fanout possibilities, FP, is calculated using the function ?1N (Px*Sz). The resulting spatially optimized pattern has a quality score, FP/T, that is equal to or greater than 2.

Abstract: Method and apparatus for spatially optimizing the arrangement of surface mount pads on a ball grid array package. An array containing T surface mount pads with a diameter less than or equal to 0.4 millimeter is arranged in an array of rows and columns less than or equal to 0.5 millimeters center-to-center. The array of pads is subdivided into N groups of pads respectively numbered Gx (for X from 1 to N), each group containing Px pads (for X from 1 to N). Each pad in each group is located so as to maximize the number of empty spaces Sz that are adjacent to each pad, where Sz=(Gx?1). The number of fanout possibilities for each group (Px*Sz) is calculated, and then the total number of fanout possibilities, FP, is calculated using the function ?1N (Px*Sz). The resulting spatially optimized pattern has a quality score, FP/T, that is equal to or greater than 2.

Abstract: A location determination device (104) is worn on a user's head to facilitate searching and tracking for another individual carrying a portable radio (102) as well as locating exit routes. At least two antennas (108), a monopulse receiver (110) and a display are integrated into the location determination device (104). Location determination device (104) scans for an incoming signal (106) from the portable device (102) and coverts the signal into angular location data. The location data and egress information are displayed to the peripheral vision of the user of the location determination device (104).

Abstract: A method for shielding one or more circuits (21, 21?) of a printed circuit board includes depositing a layer of dielectric material (43) over a printed circuit board substrate (22) and the printed circuits (21, 21?), creating a trench-like opening (44) in the dielectric layer (43) such that the trench-like opening (44) surrounds the one or more circuits (21, 21?) to be shielded, depositing a layer of metal (27) over the layer of dielectric material (43) and within the trench-like openings (44), creating a solder pad (24) at each location where an electrical connection is to be made to the printed circuits (21, 21?) by removing a border of the metal layer (27) surrounding each connection location, and providing a microvia (25) through each solder pad (24) penetrating the dielectric layer (43) and terminating at the metal of the printed circuit (21, 21?).

Abstract: A location determination device (104) is worn on a user's head to facilitate searching and tracking for another individual carrying a portable radio (102) as well as locating exit routes. At least two antennas (108), a monopulse receiver (110) and a display are integrated into the location determination device (104). Location determination device (104) scans for an incoming signal (106) from the portable device (102) and coverts the signal into angular location data. The location data and egress information are displayed to the peripheral vision of the user of the location determination device (104).

Abstract: A method for shielding one or more circuits (21, 21?) of a printed circuit board includes depositing a layer of dielectric material (43) over a printed circuit board substrate (22) and the printed circuits (21, 21?), creating a trench-like opening (44) in the dielectric layer (43) such that the trench-like opening (44) surrounds the one or more circuits (21, 21?) to be shielded, depositing a layer of metal (27) over the layer of dielectric material (43) and within the trench-like openings (44), creating a solder pad (24) at each location where an electrical connection is to be made to the printed circuits (21, 21?) by removing a border of the metal layer (27) surrounding each connection location, and providing a microvia (25) through each solder pad (24) penetrating the dielectric layer (43) and terminating at the metal of the printed circuit (21, 21?).

Abstract: Methods for forming a metal shield on a printed circuit board (10) include depositing a first layer of metal (41) on a substrate (22) of the printed circuit board (10), depositing a first layer of dielectric material (42) on the first layer of metal (41), printing one or more circuits (21, 21?) on the first dielectric layer (42), depositing a second layer of dielectric material (43) over the one or more printed circuits (21, 21?), forming a trench-like opening (44) in the two layers of dielectric material (42, 43) surrounding the one or more printed circuits (21, 21?) so that the metal of the first layer (41) is exposed by the trench-like opening (44), depositing a second layer of metal (27) on the second layer of dielectric material (43) such that the second layer of metal (27) plates the trench-like opening (44) and makes electrical contact with the first metal layer (41).

Abstract: A method of forming a coaxial transmission line on a high density PCB. A metal layer (102) on the PCB (104) forms the bottom part of the shield, and is covered by a first dielectric (112). Two parallel trenches (122) are formed in the first dielectric to reveal part (123) of the metal strip. The signal conductor (132) is then formed on the first dielectric. A second dielectric (142) covers the signal conductor and the first dielectric. A second set of two parallel trenches (172) are formed in the second dielectric immediately above the first two trenches. Metal deposit (182) is plated in the parallel trenches to contact the metal strip, and also covers a portion of the second dielectric that lies between the trenches, to create a shield. The resulting coaxial transmission line has a center conductor insulated from the shield by the dielectrics.

Abstract: Methods and apparatus for forming a metal shield on a printed circuit board (10) include a layer of dielectric material (23) one or more printed circuits (21) on the layer of dielectric material (23), a layer of metal (27) on the layer of dielectric material (23), a metal-clad trench or opening surrounding the printed circuit (44) and electrically connected to the layer of metal(27), a solder pad (24) on the layer of dielectric material (23), a microvia (25) through the solder pad (24) and the layer of dielectric material (23), and electrical components (11) soldered to the solder pads (24) and to the printed circuit (21).

Abstract: Methods and apparatus for forming a metal shield on a printed circuit board (10) include a layer of dielectric material (23) one or more printed circuits (21) on the layer of dielectric material (23), a layer of metal (27) on the layer of dielectric material (23), a metal-clad trench or opening surrounding the printed circuit (44) and electrically connected to the layer of metal(27), a solder pad (24) on the layer of dielectric material (23), a microvia (25) through the solder pad (24) and the layer of dielectric material (23), and electrical components (11) soldered to the solder pads (24) and to the printed circuit (21).

Abstract: An electrostatic discharge protection device for a high-density printed circuit board consists of a layered structure starting at the bottom layer with a ground conductor. A dielectric layer covers the ground conductor to electrically isolate it from a circuit trace that is on top of the dielectric layer. A via is formed in the dielectric layer such that a portion of the ground conductor is exposed, and the via is strategically located such that the edge of the via is tangent to an edge portion of the circuit trace. The via forms a spark gap between the edge portion of the circuit trace and the underlying ground conductor, using air as the dielectric medium.

Abstract: Methods and apparatus for forming a metal shield on a printed circuit board (10) include a layer of dielectric material (23) one or more printed circuits (21) on the layer of dielectric material (23), a layer of metal (27) on the layer of dielectric material (23), a metal-clad trench or opening surrounding the printed circuit (44) and electrically connected to the layer of metal (27), a solder pad (24) on the layer of dielectric material (23), a microvia (25) through the solder pad (24) and the layer of dielectric material (23), and electrical components (11) soldered to the solder pads (24) and to the printed circuit (21).

Abstract: A method of forming a coaxial transmission line on a high density PCB. A metal strip (102) on the PCB (104) forms the bottom part of the shield, and is covered by a first dielectric (112). Two parallel trenches (122) are formed in the first dielectric to reveal part (123) of the metal strip. The signal conductor (132) is then formed on the first dielectric. A second dielectric (142) covers the signal conductor and the first dielectric. A second set of two parallel trenches (172) are formed in the second dielectric immediately above the first two trenches. Metal (182) is plated in the parallel trenches to contact the metal strip, and also covers a portion of the second dielectric that lies between the trenches, to create a shield. The resulting coaxial transmission line has a center conductor insulated from the shield by the dielectrics.