Low voltage supply amplifier
AssigneeInfineon Technologies AG
InventorSaverio Trotta
Life of this patent
Estimating the term…
Abstract
A circuit includes a differential input pair stage including bipolar transistors and configured to receive an RF input signal; a cascode stage coupled between the differential input pair stage and an output node, the cascode stage including bipolar transistors; and a current source including a first bipolar transistor coupled to a first output of the differential input pair stage and a second bipolar transistor coupled to a second output of the differential input pair stage.
Claims25
A circuit comprising:
- a differential input pair stage comprising bipolar transistors and configured to receive an RF input signal;
- a cascode stage coupled between the differential input pair stage and an output node, the cascode stage comprising bipolar transistors;
- and
- a current source comprising a first bipolar transistor coupled to a first output of the differential input pair stage and a second bipolar transistor coupled to a second output of the differential input pair stage, wherein the differential input pair stage is coupled to a first reference voltage node and is further coupled to a first resistor coupled to a ground terminal, and the current source is coupled to the first reference voltage node and is further coupled to a second resistor coupled to the ground terminal.
A method of operating an RF amplifier comprising a differential input pair stage comprising bipolar transistors, the differential input pair stage coupled to a first resistor coupled to ground, a cascode stage comprising bipolar transistors and having an input coupled to an output of the differential input pair stage, and a current source comprising bipolar transistors having an output coupled to the output of the differential input pair stage, the current source coupled to a second resistor coupled to ground, the current source further coupled to a reference voltage node, the method comprising:
- receiving an RF input signal with the differential input pair stage, wherein the differential input pair stage is coupled to the reference voltage node;
- providing a reference voltage to the reference voltage node;
- generating a first bias current with the current source by biasing the current source with the reference voltage;
- generating a second bias current by adding the first bias current with a current flowing through the differential input pair stage;
- applying the second bias current to the cascode stage;
- and
- generating an RF output signal with the cascode stage based on the RF input signal.
An RF amplifier comprising:
- a first bipolar transistor comprising
- a base coupled to a first differential input node and to a first reference voltage node, and
- an emitter coupled to a first supply terminal through a first resistor;
- a second bipolar transistor comprising
- a base coupled to a second differential input node and to the first reference voltage node, and
- an emitter coupled to the first supply terminal through the first resistor;
- a third bipolar transistor comprising
- an emitter coupled to a collector of the first bipolar transistor, and
- a collector coupled to a second supply terminal;
- a fourth bipolar transistor comprising
- an emitter coupled to a collector of the second bipolar transistor, and
- a collector coupled to the second supply terminal;
- a fifth bipolar transistor comprising
- a collector coupled to the collector of the third bipolar transistor, and
- a base coupled to the first reference voltage node;
- and
- a sixth bipolar transistor comprising
- a collector coupled to the collector of the fourth bipolar transistor, and
- a base coupled to the first reference voltage node.
Dependencies are inferred from the claim text.