Switched gain amplifier circuit
AssigneeRF Micro Devices, Inc.
InventorsDavid Q. Ngo, Mike B. Thomas, Christopher B. Foye
Life of this patent
Estimating the term…
Abstract
An amplifier chain that switches between a saturated mode of operation and a linear mode of operation comprises at least two amplifier stages. A switch is associated with the first amplifier stage and dampens the gain of the amplifier chain when the switch is closed. In a first embodiment, this is done by bypassing the first amplifier stage. In second and third embodiments, this is done by providing a feedback loop to the first amplifier stage. Dynamic device scaling and changing the bias may also be used to affect the performance of the amplifier chain.
Claims36
An amplifier chain, comprising:
- a first amplifier stage;
- a final amplifier stage in series with said first amplifier stage;
- a switch associated with said first amplifier stage;
- said first and final amplifier stages operating in a saturated mode when said switch is open;
- and
- said first amplifier stage being bypassed when said switch is closed and said final amplifier stage operating in a linear mode when said switch is closed.
An amplifier chain comprising:
- a first amplifier stage;
- a final amplifier stage positioned in series with said first amplifier stage;
- a feedback loop comprising a switch and a impedance element, said feedback loop associated with said first amplifier stage;
- said amplifier stages operating in a saturated mode when said switch is open;
- and
- said amplifier stages operating in a linear mode when said switch is closed.
An amplifier chain comprising:
- a first amplifier stage;
- a final amplifier stage positioned in series with said first amplifier stage;
- a switch associated with said first amplifier stage;
- said final amplifier stage comprising a plurality of transistors cells arranged in a parallel array;
- said amplifier chain operating in a first mode when said switch is open and in a second mode when said switch is closed;
- and
- said plurality of transistor cells all operating in said first mode and a portion of said plurality of transistor cells operating in said second mode.
A method of controlling an amplifier chain with a plurality of amplifier stages, comprising:
- providing a switch associated with a first amplifier stage in the amplifier chain;
- operating the amplifier chain in a first mode when said switch is open, said first mode comprising operating the amplifier stages in a saturated mode;
- operating the amplifier chain in a second mode when said switch is closed, said second mode comprising operating at least one of said amplifier stages in a linear mode;
- dampening gain associated with said first amplifier stage when said switch is closed;
- and
- increasing a bias control signal to at least one of said amplifier stages when said switch is closed.
Dependencies are inferred from the claim text.