Patent
Circuit to protect rf output amplifier against mismatch damage
TLDR
In this article, a mismatch protection circuit is proposed to protect power output transistors of a communications transmitter from damaging excessive reflected power, as might occur when the antenna is disconnected or broken, which circuit continuously monitors and compares parameters indicative of forward and reflected power or VSWR and when there is excessive mismatch, instantaneously cuts back the dc power delivered to the transistors to a safe low level, but a level sufficient for continued cutback operation of the protection circuit, when and for so long as the excessive mismatch continues.Abstract:
A mismatch protection circuit to protect power output transistors of a communications transmitter from damaging excessive reflected power, as might occur when the antenna is disconnected or broken, which circuit continuously monitors and compares parameters indicative of forward and reflected power or VSWR and when there is excessive mismatch, instantaneously cuts back the dc power delivered to the output transistors to a safe low level, but a level sufficient for continued cutback operation of the protection circuit, when and for so long as the excessive mismatch continues.read more
Citations
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Patent
Systems and methods for controlling output power in a communication device
TL;DR: In this article, a mismatch detector including a directional device adapted to couple signals across the device and a detector coupled to a port on the directional device and configured to measure a reflected power is presented.
Patent
Rf power amplifier circuit
TL;DR: In this paper, a RF power amplifier circuit has at least one power transistor and a protection circuit protecting the power transistor against high voltages that lead to a destructive breakdown of the transistor.
Patent
Systems and Methods of RF Power Transmission, Modulation, and Amplification
TL;DR: In this article, an apparatus, system, and method for energy conversion is described, which can include a trans-impedance node, a reactive element, and a trans impedance circuit.
References
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Patent
Amplifier protection circuit
TL;DR: In this article, a protection circuit for a transmitter amplifier is provided which senses the forward power level and develops a first voltage which is compared with a reference voltage to provide a control voltage which controls the power developed by the transmitter amplifier.
Patent
Transistor protection circuit
TL;DR: In this article, a protection circuit for use with a transistor amplifier comprises a normally nonconductive transistor adapted to be connected across the input and output terminals of the output transistors of a power amplifier.