Back to results
US 6,856,200 B1Granted
Protection circuit and method for RF power amplifiers in WLAN tranceivers
AssigneeMarvell International Ltd.
InventorsShuran Wei, Lawrence Tse, Sehat Sutardja
Life of this patent
Estimating the term…
Abstract
A protection circuit for a power amplifier of a radio frequency transmitter includes a sensing circuit that generates a sensed signal based on an output of the power amplifier. A reference signal generator generates a reference signal. A comparator communicates with the sensing circuit and the reference signal generator and outputs a first state when the reference signal exceeds the sensed signal and a second state when the sensed signal exceeds the reference signal. A turn off circuit turns off the power amplifier when the comparator is in the second state.
Claims36
A protection circuit for protecting a power amplifier, comprising:
- a sensing circuit that generates a sensed signal based on an output of said power amplifier;
- a reference signal generator that generates a reference signal;
- and
- a comparator that communicates with said sensing circuit and said reference signal generator and that outputs a first state when said reference signal exceeds said sensed signal and a second state when said sensed signal exceeds said reference signal,
- wherein said comparator communicates with said power amplifier and suppresses AC signals applied to said power amplifier when said comparator is in said second state.
2 more elements
A protection circuit for protecting a power amplifier, comprising:
- a sensing circuit that generates a sensed signal based on an output of said power amplifier;
- a reference signal generator that generates a reference signal;
- and
- a comparator that communicates with said sensing circuit and said reference signal generator and that outputs a first state when said reference signal exceeds said sensed signal and a second state when said sensed signal exceeds said reference signal, wherein said power amplifier includes a transistor and wherein said comparator turns off said transistor prior to breakdown of said transistor,
- wherein said sensing circuit includes first and second transistors having a control terminal that is biased at a first voltage, first terminals that communicate with positive and negative outputs of said power amplifier, and second terminals that communicate with one input of said comparator.
2 more elements
A protection circuit for protecting a power amplifier, comprising:
- a sensing circuit that generates a sensed signal based on an output of said power amplifier;
- a reference signal generator that generates a reference signal;
- and
- a comparator that communicates with said sensing circuit and said reference signal generator and that outputs a first state when said reference signal exceeds said sensed signal and a second state when said sensed signal exceeds said reference signal, wherein said power amplifier includes a transistor and wherein said comparator turns off said transistor prior to breakdown of said transistor;
- and
- a turn-off circuit that turns said power amplifier off when said comparator is in said second state.
3 more elements
A protection circuit for protecting a power amplifier, comprising:
- sensing means for generating a sensed signal based on an output of said power amplifier;
- reference signal generating means for generating a reference signal;
- and
- comparing means for communicating with said sensing means and said reference signal generating means and for outputting a first state when said reference signal exceeds said sensed signal and a second state when said sensed signal exceeds said reference signal,
- wherein said comparing means communicates with said power amplifier and suppresses AC signals applied to said power amplifier when said comparing means is in said second state.
2 more elements
A protection circuit for protecting a power amplifier, comprising:
- sensing means for generating a sensed signal based on an output of said power amplifier;
- reference signal generating means for generating a reference signal;
- and
- comparing means for communicating with said sensing means and said reference signal generating means and for outputting a first state when said reference signal exceeds said sensed signal and a second state when said sensed signal exceeds said reference signal,
- wherein said power amplifier includes a transistor and wherein said comparing means turns off said transistor prior to breakdown of said transistor.
2 more elements
A protection circuit for protecting a power amplifier, comprising:
- sensing means for generating a sensed signal based on an output of said power amplifier;
- reference signal generating means for generating a reference signal;
- and
- comparing means for communicating with said sensing means and said reference signal generating means and for outputting a first state when said reference signal exceeds said sensed signal and a second state when said sensed signal exceeds said reference signal, wherein said sensing means includes first and second transistors having a control terminal that is biased at a first voltage, first terminals that communicate with positive and negative outputs of said power amplifier, and second terminals that communicate with one input of said comparing means.
1 more element
A method for protecting a power amplifier, comprising:
- generating a sensed signal based on an output of said power amplifier;
- generating a reference signal;
- outputting a first state when said reference signal exceeds said sensed signal and a second state when said sensed signal exceeds said reference signal;
- and
- suppressing AC signals applied to said power amplifier when in said second state.
2 more elements
A method for protecting a power amplifier, comprising:
- generating a sensed signal based on an output of said power amplifier;
- generating a reference signal,
- outputting a first state when said reference signal exceeds said sensed signal and a second state when said sensed signal exceeds said reference signal;
- and
- turning off said transistor prior to breakdown of said transistor.
2 more elements
A protection circuit for protecting a power amplifier, comprising:
- a direct sensing circuit that directly senses an output of said power amplifier and that generates a sensed signal based on said directly sensed output of said power amplifier;
- a reference signal generator that generates a reference signal;
- and
- a comparator that communicates with said direct sensing circuit and said reference signal generator and that outputs a first state when said reference signal exceeds said directly sensed signal and a second state when said directly sensed signal exceeds said reference signal.
1 more element
A protection circuit for protecting a power amplifier, comprising:
- direct sensing means for directly sensing an output of said power amplifier and for generating a sensed signal based on said directly sensed output of said power amplifier;
- reference signal generating means for generating a reference signal;
- and
- comparing means for communicating with said sensing means and said reference signal generating means and for outputting a first state when said reference signal exceeds said directly sensed signal and a second state when said directly sensed signal exceeds said reference signal.
1 more element
Dependencies are inferred from the claim text.