Motorola Corporation

Sin Kai Henry Lau

Glenn A Watanabe

Thomas E Schiltz

A low noise amplifier ( ) having an amplifier mode and a bypass mode. In the amplifier mode the input signal received at an input terminal ( ) is amplified by an amplifying transistor ( ) and the output signal supplied at an output terminal ( ). In the bypass mode the input signal is not amplified, but transferred by a bypass circuit ( ) from the base to the collector of the amplifying transistor. An input impedance matching circuit ( ) and an output impedance matching circuit ( ), along with the bypass circuit ( ) provide a constant input and output impedance when the low noise amplifier ( ) operates in the amplifier mode and the bypass mode.

Low noise amplifier having bypass circuitry

A radio frequency single to differential buffer amplifier provides a 180 degree phase difference between two output signals by using a current mirroring circuit and using different referencing on the two output signals. Fine adjustment on the phase of the two output signals can be done by adjusting a phase adjustment device embedded in a cascode amplifier. High input power handling capability is accomplished by class AB operation on two input transistors in the amplifier.

Single-to-differential buffer amplifier

The present invention concerns a method for variable linear amplification and an apparatus for a variable linear amplifier, which is particularly suited for RF communication applications. One embodiment includes a high gain circuit in communication with a transconductor to receive an RF signal, a low gain circuit in communication with the transconductor and a current dissipation circuit in communication with the transconductor and a ground source. In one embodiment, the high gain circuit is a NMOS device which is characteristically larger than the low gain device.

Growing community of inventors

Scottsdale, AZ, United States of America

Sin Kai Henry Lau