Differential digital step attenuators with leakage cancellation

Abstract

An attenuator circuit includes a differential input having first and second inputs, and a differential output having first and second outputs. The attenuator circuit further includes a first transistor coupled between the first input and the first output, a second transistor coupled between the second input and the second output, a third transistor coupled between the first input and the second output, and a fourth transistor coupled between the second input and the first output. During a pass-through state, the first and second transistors are enabled, and the third and fourth transistors may be disabled. During an attenuation state, the first, second, third, and fourth transistors are all disabled. An attenuator network (e.g., T or Pi network) may have its differential input terminals coupled to the first and second inputs of the differential input, and its differential output terminals coupled to the first and second outputs of the differential output.

Dependencies are inferred from the claim text.