RF power amplifier circuit
First Claim
1. A RF power amplifier circuit having at least one output power transistor and a protection circuit protecting the power transistor against high voltages that lead to a destructive breakdown of the power transistor, the circuit comprising:
- (a) a biasing circuit (6) comprising a voltage-to-current convener and a biasing transistor, said biasing circuit biasing the power transistor (2);
(b) a peak detector (8) detecting the output voltage of the power transistor, and(c) a comparator circuit (12) connected to the peak detector (8) and designed to reduce the base current of the power transistor (2) when controlled by the peak detector.
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Accused Products
Abstract
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. The circuit comprises a power transistor (2), a biasing circuit (6) biasing the power transistor; a peak detector (8) measuring the output voltage of the power transistor; and a comparator circuit (12) connected to the peak detector (8) and designed to reduce the base current of the power transistor (2) when controlled by the peak detector (8).
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Citations
14 Claims
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1. A RF power amplifier circuit having at least one output power transistor and a protection circuit protecting the power transistor against high voltages that lead to a destructive breakdown of the power transistor, the circuit comprising:
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(a) a biasing circuit (6) comprising a voltage-to-current convener and a biasing transistor, said biasing circuit biasing the power transistor (2); (b) a peak detector (8) detecting the output voltage of the power transistor, and (c) a comparator circuit (12) connected to the peak detector (8) and designed to reduce the base current of the power transistor (2) when controlled by the peak detector. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13)
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14. A wireless communication device comprising an RF power amplifier circuit having at least one output power transistor and a protection circuit protecting the power transistor against high voltages that lead to a destructive breakdown of the power transistor, the circuit comprising:
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(a) a biasing circuit (6) comprising a voltage-to-current converter and a biasing transistor, said biasing the power transistor (2); (b) a peak detector (8) detecting the output voltage of the power transistor; and (c) a comparator circuit (12) connected to the peak detector (8) and designed to reduce the base current of the power transistor (2) when controlled by the peak detector.
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Specification