Abstract: A small size, low cost balun is formed on a substrate, such as gallium arsenide, as an integrated passive device. Multiple baluns are formed on a same substrate, allowing multi-band operation. For example, symmetrical transformers are provided for two different bands of operation, such as for a quad-band GSM application. Each of the two different baluns is used for two different frequency bands of operation of the quad-band device. A ground ring allows two Hi-Q baluns to be formed on the same integrated circuit side-by-side with minimum spacing and minimum impact on phase and amplitude performance over the frequency bands of operation. By using multiple integrated circuit baluns on a same substrate or chip, the size and cost of baluns for multi-band operation may be reduced.

Abstract: A small size, low cost balun is formed on a substrate, such as gallium arsenide, as an integrated passive device. Multiple baluns are formed on a same substrate, allowing multi-band operation. For example, symmetrical transformers are provided for two different bands of operation, such as for a quad-band GSM application. Each of the two different baluns is used for two different frequency bands of operation of the quad-band device. A ground ring allows two Hi-Q baluns to be formed on the same integrated circuit side-by-side with minimum spacing and minimum impact on phase and amplitude performance over the frequency bands of operation. By using multiple integrated circuit baluns on a same substrate or chip, the size and cost of baluns for multi-band operation may be reduced.

Abstract: In a particular embodiment, an oscillator adjustment circuit is disclosed. The oscillator adjustment circuit includes a resonator portion comprising a capacitive element coupled to an inductive element and a signal balancing portion comprising a secondary coil of the transformer. The inductive element comprises a primary coil of a transformer. The secondary coil has a grounded center tap.

Abstract: A variable gain control amplifier (10) and method provides a substantially constant input impedance and output impedance, and provides a substantially constant noise figure and third order harmonic. The variable gain control amplifier (10) includes an amplifier stage including at least a first intermediate fixed gain stage (22) operative to produce a first intermediate signal (30) in response to the input signal (20). The variable gain control amplifier (10) further includes at least a second intermediate fixed gain stage (24) operative to produce an output signal (18) in response to the first intermediate signal (30). A feedback circuit (16) is operative to produce a gain control signal (32) in response to the output signal (18). A gain control circuit (26) is coupled to the at least first intermediate fixed gain stage (22) and the second intermediate fixed gain stage (24), and receives the gain control signal (32) to control an amplitude of the intermediate signal (30).

Abstract: A variable gain control amplifier (10) and method provides a substantially constant input impedance and output impedance, and provides a substantially constant noise figure and third order harmonic. The variable gain control amplifier (10) includes an amplifier stage including at least a first intermediate fixed gain stage (22) operative to produce a first intermediate signal (30) in response to the input signal (20). The variable gain control amplifier (10) further includes at least a second intermediate fixed gain stage (24) operative to produce an output signal (18) in response to the first intermediate signal (30). A feedback circuit (16) is operative to produce a gain control signal (32) in response to the output signal (18). A gain control circuit (26) is coupled to the at least first intermediate fixed gain stage (22) and the second intermediate fixed gain stage (24), and receives the gain control signal (32) to control an amplitude of the intermediate signal (30).

Abstract: In a particular embodiment, an oscillator adjustment circuit is disclosed. The oscillator adjustment circuit includes a resonator portion comprising a capacitive element coupled to an inductive element and a signal balancing portion comprising a secondary coil of the transformer. The inductive element comprises a primary coil of a transformer. The secondary coil has a grounded center tap.

Abstract: A method for operating a wide band voltage controlled oscillator comprises using a control voltage to tune the capacitance of at least one hybrid n+ and p+ gate-doped voltage variable capacitor of the wide band voltage controlled oscillator. A hybrid voltage variable capacitor includes a substrate, a well adjacent to the substrate, a first and second set of contact elements adjacent to the well, a first channel layer adjacent to the well and bound by the first set of contact elements, a first insulating layer adjacent to the first channel layer, a first electrode adjacent to the first insulating layer, a second channel layer adjacent to the well and bound by the second set of contact elements, a second insulating layer adjacent to the second channel layer, and a second electrode adjacent to the second insulating layer.

Abstract: A method for operating a wide band voltage controlled oscillator comprises using a control voltage to tune the capacitance of at least one hybrid n+ and p+ gate-doped voltage variable capacitor of the wide band voltage controlled oscillator. A hybrid voltage variable capacitor includes a substrate, a well adjacent to the substrate, a first and second set of contact elements adjacent to the well, a first channel layer adjacent to the well and bound by the first set of contact elements, a first insulating layer adjacent to the first channel layer, a first electrode adjacent to the first insulating layer, a second channel layer adjacent to the well and bound by the second set of contact elements, a second insulating layer adjacent to the second channel layer, and a second electrode adjacent to the second insulating layer.