Apple Inc.
Transformer-based wideband filter with ripple reduction

Abstract:

A radio frequency filtering circuitry includes a first inductor, a second inductor, and a conductive loop. The first inductor receives a first current that induces a second current in the second inductor upon receiving the first current. The first inductor and/or the second inductor induce a third current in the conductive loop. The conductive loop adjusts the third current to reduce a first gain peak of an output signal to correlate to a second gain peak of the output signal.