Abstract: A mobile station (102) has electrical circuitry (301) that operates to reduce power consumption. A synthesizer (318) is tuned so that a receiver (314) receives a home radio frequency (RF) signal during a receive slot (504) of a PCH subframe (209). A controller (310) detects if an upcoming subframe has an uplink requirement and if data from the home RF signal indicates that an idle condition exists. If the upcoming subframe does not have an uplink requirement, synthesizer (318) is tuned during a long idle slot (506) of PCH subframe (209) to measure signal strengths of two peripheral RF signals. If the idle condition does exist, electrical circuitry (301) is placed into a low power mode throughout a transmit slot (508), a receive slot (512), a long idle slot (514), and a transmit slot (516).

Abstract: A voltage reference generator (200) generates a temperature compensated voltage at an output (202). The voltage reference generator includes a first transistor (204) and a second transistor (206) series connected between a supply voltage and the output. The first transistor and the second transistor establishing the temperature compensated voltage in response to a bias current (I.sub.BIAS) and a first bias voltage and a second bias voltage. The voltage reference generator further includes a current source (208) coupled to the first transistor and the second transistor to establish the bias current in the first transistor and the second transistor. The current source produces the first bias voltage and the second bias voltage.

Abstract: A level detector detects an input signal level. A rectifier (210) receives the input signal and provides a rectified signal. A prefilter (220) receives the rectified signal and attenuates high frequency components at frequencies near multiples of a decimation sample rate. The prefiltered signal is decimated (230) and low pass filtered by a lowpass filter (240) having a passband below the input frequency of the input signal. The level detector can be provided to control a variable gain stage circuit (935, 1010) which applies a gain to the input signal based on the level to form a dynamic range compressor or expander.

Abstract: A method for synchronizing base stations (104, 106, 108, 110) or radio ports in a communication system (100) such as a cordless or cellular telephone system uses a mobile station (114) or handset for synchronizing unsynchronized base stations. The mobile station (114) is first synchronized to a reference base station. The mobile station (114) then initiates communication with the unsynchronized base station and calculates a synchronization adjustment. The mobile station (114) transmits the synchronization adjustment to the unsynchronized base station which uses the synchronization adjustment to adjust its time base.

Abstract: An electronic device such as a radiotelephone (100) includes a bottom housing (108) defining a first hinge aperture (2207) and a slot (2208) adjacent the first hinge aperture. A top housing (102) defines a second hinge aperture (2223) having an inner rotation surface (2226). A shaft (2210) extends from the first housing at the first hinge aperture. The shaft is sized for insertion in the second hinge aperture and terminates in a bearing surface (2216), the inner rotation surface pivoting on the bearing surface as the second housing moves in relation to the first housing. The shaft and the bearing surface both define a shaft slot (2218) aligned with the slot in the first housing for routing a flexible circuit element (216) between the first housing and the second housing.

Abstract: Dual band voltage controlled oscillators (VCOs) incorporate a combiner circuit with a single output operable at two widely separated frequency bands such as 900 MHz and 1.8 GHz, for example. The combiner circuit includes a duplexer used as a combiner on the outputs of the VCOs. The duplexer can be realized in transmission line or inductor configurations. The use of the duplexer improves spurious performance and phase noise by more than 10 dB between the two operating frequency bands and supplies band rejection at the non-operating frequency.

Abstract: In a time division, multiple access system, a base station (102) transmits an isochronous beacon (404, 422) at the start of each frame (400), conveying control and timing information. Following the isochronous beacon (404), isochronous time slots (414, 416, 418, 420) are dynamically allocated for communication of isochronous data. After communication of the isochronous data, the remainder of the frame (400) before the next isochronous beacon (422) is used for transmission of packets of asynchronous data. This technique gives priority to the isochronous data, which is real time, while also maximizing the bandwidth allocated for asynchronous data. A single transmitter circuit (124, 158) and receiver circuit (122, 156) at each station are used for communication of both isochronous data and asynchronous data.

Abstract: A combined radiotelephone and paging device (101), hereinafter the combined unit, normally operates as a radiotelephone. In response to a predetermined condition, the combined unit operates as a paging device. The predetermined conditions include low battery voltage and poor communication channel quality or a request signal from a remote transceiver (109) of the radiotelephone system. The paging system and the radiotelephone system may be independent communication systems or they may be a single communication system. The combined unit (101) and its unique switching characteristics allows the combined unit (101) to utilize the paging devices beneficial qualities of lower power consumption and broader service range to enhance the usefulness of a radiotelephone.

Abstract: A portable radio communication device (102) includes a housing (302), and a transmitter (906) and control circuitry (902) disposed in the housing (302). The housing (302) is configured to carry a first battery source (112) and to optionally simultaneously carry a second battery source (114). The control circuitry (902) configures the transmitter (906) to transmit in accordance with a first set of power levels when the second battery source (114) is available, and in accordance with a second set of power levels when the second battery source (114) is unavailable. The first set of power levels includes at least one power level greater than any of the second set of power levels.

Abstract: A digital-to-analog converter with cascaded coarse and fine resistor divider strings. The fine resistor string contains 2.sup.N or more resistor segments controlled by N number of fine divider control bits. Resistors located at each end of the fine divider string are a fraction of the nominal value for the remaining fine divider resistor segments. The on-resistance of switches coupling the coarse and fine resistor divider strings is less than or equal to a predetermined fraction of the nominal value for the fine divider resistor segments to minimize contributions to linearity error. The DAC uses all CMOS devices including NMOS and PMOS switches which utilize approximately the full rail-to-rail voltage of the voltage source without the use of additional amplifiers. The DAC provides linearity of about one-fourth LSB.

Abstract: A multilayer ceramic package 200 with a center ground via 202 for size reduction is disclosed. Package 200 includes dielectric layers 204A-204G each having a major surface 206. The package also includes an input electrode 208 and an output electrode 210 as well as a top ground plane 212 and a bottom ground plane 214. Package 200 includes a substantially spiral transmission line structure made from electrodes 216. Package 200 also includes a ground via 202 extending vertically through the plurality of dielectric layers 204A-204G. The center ground via 202 is substantially centered inside the substantially spiral transmission line structure and electrically isolated therefrom and connected to the top ground plane 212 and the bottom ground plane 214.

Abstract: A peak detector circuit (100) includes an output transconductance amplifier (102), a current rectifier (104) and an averaging circuit (108). The current rectifier includes an amplifier (115) which reduces input impedance of the current rectifier to increase the operating frequency of the peak detector circuit. An isolator (106) employs a current mirror (509) with a cascode transistor (512) having a bias potential which is dynamically adjusted to achieve accurate mirroring. An amplifier of a common mode feedback circuit (110) has improved linearity.

Abstract: A communications unit includes a processor (11), a data bus (12), an address bus (13), memory means (14,15,16), a data interface (36) between the data bus and a host computer (35), and a monitoring interface (30) with the host computer. The monitoring interface (30) includes monitoring address generating means fed from the host computer and including a bank register (31) loadable by the host computer as its high-order portion and a direct path (32) from the host computer as its low order portion. The monitoring interface also includes address coupling means (18) for passing the contents of the monitoring address generating means to the address bus (13) to address the memory means (14,15,16) of the communications unit directly. The host computer can also write to the unit via the monitoring interface.

Abstract: A dual mode communication device (102) includes a first radio (124) operable according to a first mode and a second radio (126) operable according to a second mode. A common user interface (130) controls both the first radio and the second radio. Using two, complete, preexisting radios reduces development and manufacturing costs of the dual mode communication device.

Abstract: A method (100) for tuning a voltage controlled oscillator by changing electrical circuit parasitics includes a first step (102) of providing a voltage controlled oscillator circuit on a circuit board and a plurality of different metal lids each having different numbers, sizes and locations of holes. Each different lid presents a different electrical circuit parasitic to the voltage controlled oscillator. In a second step (104), the voltage controlled oscillator frequency is measured, and the frequency shift needed to achieve a desired operating frequency is calculated in a third step (106). In a fourth step (108), a lid is chosen that will present the parasitics needed to provide the amount of frequency shift needed. As a last step (110), the chosen lid is attaching to the circuit board to obtain the desired nominal operating frequency from the voltage controlled oscillator.

Abstract: A multilayer ceramic package (200) with a floating element (202) to couple transmission lines (214) is disclosed. The package (200) has numerous dielectric layers (204A-204I) including an input electrode (206), an output electrode (208), a top ground plane (210) and a bottom ground plane (212). Transmission lines (214) are formed on some of the dielectric layers (204A-204I). Floating element (202) adjusts the electrical coupling between the transmission lines (214) and is spatially separated therefrom. This may provide the advantage of increased capacitive coupling between transmission line resonator structures in a multilayer packages, including non-adjacent resonant structures, without increasing the overall dimensions of the package (200). The floating element (202) may also increase the operable passband of a multilayer bandpass filter or provide a low-side transmission zero.

Abstract: Performance of a radiotelephone (104) in a CDMA communication system (100) is enhanced using a receiver searcher (114) that includes a matched filter (128) to capture the pilot energies of all receivable transmissions from a base station (102) and other nearby base stations. A detected PN sequence is compared with a predetermined PN sequence stored at the radiotelephone (104). The predetermined PN sequence includes, for example, the last 512 chips in the short PN sequence used for spreading the in-phase channel and the quadrature-phase channel.

Abstract: A housing assembly (100) for an electronic device includes a first housing portion (102), a second housing portion (104), and a slidable element (106). The first and the second housing portions (102, 104) are configured to mate to form a housing (412). The slidable element (106) is slidably disposed in the housing (412), and is configured to fasten the first and the second housing portions (102, 104) when in a first position and unfasten the first and the second housing portions (102, 104) when in a second position. The housing (412) defines an opening (198) to access a positioning tab (123) of the ridable element (106).

Abstract: A comparator circuit (100) produces a binary output voltage at an output (109) in response to a time varying input signal received at an input (108). The comparator circuit includes an output circuit (106) having a first current mirror (202), a second current mirror (204), a bias circuit (206) and a helping current source (208). Bias currents are applied in response to the state of the output voltage at the output to increase the gain and the hysteresis of the output circuit.

Abstract: A power amplifier (517) for amplifying an operating signal includes an amplifier (538), an amplifier (540), and a power combiner (518) with harmonic selectivity. The power combiner (518) includes a transmission line section (541), a transmission line section (545), and a resistor (554). The transmission line section (541) is coupled to an amplifier output of the amplifier (538), and the transmission line section (545) is coupled to an amplifier output of the amplifier (540) and to the transmission line section (541). A capacitor (546) is coupled in parallel to a transmission line section (542) of the transmission line section (541), and a capacitor (548) is coupled in parallel to a transmission line section (544) of the transmission line section (545).