Thermally coupled current limiter

摘要

This disclosure relates generally to radio frequency (RF) amplification devices and methods of limiting an RF signal current. Embodiments of the RF amplification device include an RF amplification circuit and a feedback circuit. The RF amplification circuit is configured to amplify an RF input signal so as to generate an amplified RF signal that provides an RF signal current with a current magnitude. The feedback circuit is used to limit the RF signal current. In particular, a thermal sense element in the feedback circuit is configured to generate a sense current, and thermal conduction from the RF amplification circuit sets a sense current level of the sense current as being indicative of the current magnitude of the RF signal current. To limit the RF signal current, the feedback circuit decreases the current magnitude of the RF signal current in response to the sense current level reaching a trigger current level.

主权项

1. A radio frequency (RF) amplification device, comprising:
an RF amplification circuit configured to amplify an RF input signal so as to generate an amplified RF signal that provides an RF signal current with a current magnitude, wherein the RF amplification circuit is heated in accordance with the current magnitude of the RF signal current; and a feedback circuit comprising a thermal sense element, wherein:
the thermal sense element is configured to generate a sense current having a sense current level;the thermal sense element is positioned such that thermal conduction from the RF amplification circuit sets the sense current level of the sense current as being indicative of the current magnitude of the RF signal current, and such that the sense current level reaches a trigger current level of the feedback circuit in response to the current magnitude of the RF signal current being above a current magnitude limit; andthe feedback circuit is operable to decrease the current magnitude to or below the current magnitude limit in response to the sense current level of the sense current reaching the trigger current level.