Patent ID: 7145396

Claim:
A circuit for protecting devices in an RF power amplifier comprising: a power detector coupled to the output of the RF power amplifier for detecting the output power of the RF power amplifier; a peak detector coupled to one or more critical nodes in the RF power amplifier for detecting peak voltages at the one or more critical nodes, wherein the peak detector further comprises a first peak detector having an input coupled to the one or more critical nodes in the RF power amplifier, and a second peak detector having an input coupled to a reference tone; a divider circuit coupled between the peak detector and the one or more critical nodes; and power control circuitry coupled to the power detector and to the peak detector for controlling the output power of the power amplifier, wherein the power control circuitry protects devices in the RF power amplifier by decreasing the gain of the power amplifier when the peak detector detects a voltage above a voltage threshold at the one or more critical nodes in the RF power amplifier.