Measuring RF Interference in Audio Circuits

The proliferation of wireless transceivers in portable applications has led to increased attention to an electronic circuits’ ability to operate in the vicinity of high frequency radio transmitters. For example, in a Bluetooth headset using op amp for the voice band audio, special shielding in conjunction with good layout practice and RF suppression are needed to ensure interference-free operation of the headset. In this example, and in other gigahertz radio systems, the close proximity of the radio antenna to low frequency amplifier sub assemblies, can result in the demodulation of the radio signal causing a disruptive interference in the receiving circuit.