Step Attenuator with Constant Input Capacitance

摘要

A step attenuator with constant input capacitance and having good performance is disclosed. In an exemplary design, an apparatus includes a step attenuator having a constant input capacitance for different amounts of attenuation. The step attenuator receives an input signal, provides a variable amount of attenuation for the input signal, and provides an output signal. The step attenuator may include a plurality of attenuator sections coupled in series. Each attenuator section may include a plurality of capacitors and may have the constant input capacitance. At least one of the plurality of attenuator sections may be selected or unselected to obtain a selected amount of attenuation for the step attenuator. An attenuator section may provide a predetermined amount of attenuation or a variable amount of attenuation when selected. The apparatus may further include a power detector that receives and determines the power of the output signal from the step attenuator.

主权项

1. An apparatus comprising:
a step attenuator configured to receive an input signal, provide a variable amount of attenuation for the input signal, and provide an output signal, the step attenuator having a constant input capacitance for different amounts of attenuation.