Method and apparatus for reducing local oscillator leakage in integrated circuit receivers

摘要

Technique for reducing local oscillator leakage in integrated frequency conversion circuits is disclosed, which provides coupling an external portion of a resonator circuit to the integrated frequency conversion circuit. The coupling is accomplished without using any of the DC power or ground pins of the conversion circuit. A frequency conversion circuit based on this technique includes resonator, oscillator, and mixer circuits. Part of the oscillator and mixer circuit is encapsulated in a package, whereas at least a portion of the resonator circuit is located outside the package. The outside portion of the resonator circuit connects to at least two external resonator pins of the package such that, during the operating of the conversion circuit, the net current entering the package via said external resonator pins is approximately zero.