Abstract: Apparatus, positioned at an inlet port to a pump, for shielding the pump from a process chamber of a semiconductor wafer processing system, where the apparatus has a controllably variable effective throughput area, and method for electrically controlling the size of the effective throughput area. Specifically, the apparatus is a controllable restrictor shield supported by an actuator, having a first effective throughput area and a second effective throughput area, where the first effective throughput area is typically less than the second effective throughput area. The size of the effective throughput area is directly responsive to an electric signal that controls the actuator.
Type:
Grant
Filed:
May 12, 1997
Date of Patent:
December 14, 1999
Assignees:
Applied Materials, Inc., Motorala, Inc.
Inventors:
David Datong Huo, Bret W. Adams, John Jarvis
Abstract: A wideband phase-lock loop frequency synthesizer (200) used in a radio transceiver capable of being reconfigured to operate in either a transmit, receive, or battery save mode. The wideband phase-lock loop frequency synthesizer (200) includes, a divide-by-two divider (205), quadrature detector (204), offset VCO (209) and offset mixer (207) for generating a quadrature phase modulated signal. Moreover, a programmable filter (211) is used for removing predetermined harmonic components of the offset mixed signal enabling the synthesizer to operate over a wide frequency range.
Type:
Grant
Filed:
April 17, 1997
Date of Patent:
April 13, 1999
Assignee:
Motorala, Inc.
Inventors:
Daniel E. Brueske, Gary A. Kurtzman, Richard B. Meador
Abstract: A communication system (100) that includes a plurality of communication units (101-108) and infrastructure equipment (110-115, 140, 141) employs a method and apparatus for providing communication services to a communication unit (e.g., 101). The infrastructure equipment includes a plurality of base sites (110-115) that provide communication services to corresponding service coverage areas (120-125). The service coverage areas (120-125) are further arranged into paging location areas (130-132). When the communication unit (101) becomes active in the system (100), the communication unit (101) determines its registration type. When the communication unit (101) is of a first registration type, the communication unit (101) transmits a registration message to the infrastructure equipment (e.g., 141) whenever the unit (101) enters a new location area (130-132).