Patent attributes
Disclosed is envelope tracking circuitry having an envelope tracking integrated circuit (ETIC) coupled to a power supply to provide an envelope tracked power signal to a power amplifier (PA) with a filter equalizer configured to inject an error-correcting signal into the ETIC in response to equalizer settings. Further included is PA resistance estimator circuitry having a first peak detector circuit configured to capture within a window first peaks associated with a sense current generated by the ETIC, a second peak detector circuit configured to capture within the window second peaks associated with a scaled supply voltage corresponding to the envelope tracked power signal, comparator circuitry configured to receive the first peaks and receive the second peaks and generate an estimation of PA resistance, and an equalizer settings correction circuit configured to receive the estimation of PA resistance and update the equalizer settings in response to the estimation of PA resistance.
