Abstract: A transformer includes multiple differential ports and first and second transformer windings. The first transformer winding includes a first transformer half-winding coupled to a first differential port of the differential ports. The first transformer winding also includes a second transformer half-winding coupled to a second differential port of the differential ports. An amplifier system that has a transformer is also provided. The amplifier system includes a first and a second stage amplifier. The first stage amplifier includes a first and a second amplifier. The second stage amplifier includes a third and a fourth amplifier. The transformer is coupled between the first stage amplifier and the second stage amplifier, where the transformer has a primary loop and a secondary loop. The primary loop of the transformer may be configured to receive differential signals of the first amplifier. A method for fabricating a transformer is also provided.

Abstract: An apparatus includes a cascode amplifier. The cascode amplifier includes a first transistor and a second transistor. The cascode amplifier is configured to receive a first bias voltage, a second bias voltage, and a signal. The cascode amplifier is also configured to amplify the signal based at least on the first bias voltage and the second bias voltage. The apparatus also includes a first feedback module and a second feedback module. The first feedback module is configured to adjust the first bias voltage based at least on the amplified signal. The second feedback module is configured to adjust the second bias voltage based at least on a voltage distribution across the first transistor and the second transistor. A system and method for maintaining cascode amplifier performance are also provided.

Abstract: An apparatus includes a cascode amplifier. The cascode amplifier includes a first transistor and a second transistor. The cascode amplifier is configured to receive a first bias voltage, a second bias voltage, and a signal. The cascode amplifier is also configured to amplify the signal based at least on the first bias voltage and the second bias voltage. The apparatus also includes a first feedback module and a second feedback module. The first feedback module is configured to adjust the first bias voltage based at least on the amplified signal. The second feedback module is configured to adjust the second bias voltage based at least on a voltage distribution across the first transistor and the second transistor. A system and method for maintaining cascode amplifier performance are also provided.

Abstract: A transformer includes multiple differential ports and first and second transformer windings. The first transformer winding includes a first transformer half-winding coupled to a first differential port of the differential ports. The first transformer winding also includes a second transformer half-winding coupled to a second differential port of the differential ports. An amplifier system that has a transformer is also provided. The amplifier system includes a first and a second stage amplifier. The first stage amplifier includes a first and a second amplifier. The second stage amplifier includes a third and a fourth amplifier. The transformer is coupled between the first stage amplifier and the second stage amplifier, where the transformer has a primary loop and a secondary loop. The primary loop of the transformer may be configured to receive differential signals of the first amplifier. A method for fabricating a transformer is also provided.

Abstract: Systems and methods for maintaining power amplifier performance are provided. A system includes a bias supply that generates a bias voltage, and at least one primary power amplifier (PA) that receives the bias voltage and a primary radio frequency (RF) input. The at least one primary PA amplifies the primary RF input based on the bias voltage. The system includes an auxiliary PA that is connected in parallel with the at least one primary PA and receives the bias voltage and an auxiliary RF input, which is a scaled version of the primary RF input. The auxiliary PA amplifies the auxiliary RF input based on the bias voltage. The system includes a detector that measures an output voltage associated with the amplified auxiliary RF input, and a comparator that compares the measured output voltage to a reference voltage. The bias supply adjusts the bias voltage based on the comparison.

Abstract: A transformer has first and second transformer windings including multiple differential ports. Each of the first and second transformer windings include a first transformer half-winding coupled to a first differential port of the differential ports. Each of the first and second transformer windings also include a second transformer half-winding coupled to a second differential port of the differential ports. Each of the first and second transformer windings is divided symmetrically at a common node to form the respective first and second transformer half-windings. The first transformer half-winding is configured to form one half of an inductance in each of the first and second transformer windings. The second transformer half-winding is configured to form another half of the inductance in each of the first and second transformer windings. The common node of the first transformer winding is configured to receive a supply voltage.

Abstract: A transformer has first and second transformer windings including multiple differential ports. Each of the first and second transformer windings include a first transformer half-winding coupled to a first differential port of the differential ports. Each of the first and second transformer windings also include a second transformer half-winding coupled to a second differential port of the differential ports. Each of the first and second transformer windings is divided symmetrically at a common node to form the respective first and second transformer half-windings. The first transformer half-winding is configured to form one half of an inductance in each of the first and second transformer windings. The second transformer half-winding is configured to form another half of the inductance in each of the first and second transformer windings. The common node of the first transformer winding is configured to receive a supply voltage.

Abstract: Systems and methods for maintaining power amplifier performance are provided. A system includes a bias supply that generates a bias voltage, and at least one primary power amplifier (PA) that receives the bias voltage and a primary radio frequency (RF) input. The at least one primary PA amplifies the primary RF input based on the bias voltage. The system includes an auxiliary PA that is connected in parallel with the at least one primary PA and receives the bias voltage and an auxiliary RF input, which is a scaled version of the primary RF input. The auxiliary PA amplifies the auxiliary RF input based on the bias voltage. The system includes a detector that measures an output voltage associated with the amplified auxiliary RF input, and a comparator that compares the measured output voltage to a reference voltage. The bias supply adjusts the bias voltage based on the comparison.