发明名称 |
Power amplifiers having improved startup linearization and related operating methods |
摘要 |
Systems and methods are described for improving the startup linearization of a power amplifier. A bias network is provided to generate a bias signal during amplifier startup, and the amplifier is configured to produce an output signal in response to the input signal and the bias signal. A variable impedance is provided to couple the input signal and the output signal in parallel with the amplifier. A controller is configured to apply a weighting function to the variable impedance over at least a startup phase of the amplifier system. By applying a non-linear or other weighting function to the variable impedance during startup, the gain of the amplifier can be controlled to thereby extend a time period over which the output power of the amplifier increases in a generally linear manner toward an operating level.
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申请公布号 |
US7701285(B2) |
申请公布日期 |
2010.04.20 |
申请号 |
US20080051450 |
申请日期 |
2008.03.19 |
申请人 |
FREESCALE SEMICONDUCTOR, INC. |
发明人 |
GRIFFITHS JAMES R.;GONZALEZ DAVID M. |
分类号 |
H03F1/36 |
主分类号 |
H03F1/36 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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