Method and apparatus for controlling or managing bandwidth of a filter circuit within a system having two integrated circuits

An adjustable filter system comprising:

• a first integrated circuit comprising a first filter that is characterized by a first passband used to pass at least one desired frequency component of an input signal that is within the first passband, a first stopband used to attenuate at least one undesired frequency component of the input signal that is within the first stopband, and at least one corner frequency between the first passband and the first stopband, wherein first integrated circuit is an envelope tracking power supply circuit, and wherein the input signal is an envelope tracking signal generated from a baseband signal;
• a second integrated circuit comprising a filter control circuit configured to generate a first filter adjustment value to move the at least one corner frequency of the first filter, wherein the second integrated circuit is a transceiver integrated circuit, wherein the second integrated circuit further comprises:
• a delay adjustment circuit coupled to the filter control circuit and configured to calculate a delay of the first filter based on the first filter adjustment value to use in synchronizing timing of arrival, at a power amplifier, of a power supply signal generated from the envelope tracking signal and a radio frequency signal generated from the baseband signal;
• and
• an interface coupled between the first and second integrated circuits and configured to communicate the first filter adjustment value from the filter control circuit to the first filter.