A 10–67-GHz CMOS step attenuator with improved flatness and large attenuation range

A four-bit CMOS step attenuator is designed using a new design method to achieve improved flatness and large attenuation range from 10–67 GHz. The design method is based on the frequency-response characteristics of the conventional Pi-, T-, and distributed attenuators. Over 10–67 GHz, the measured results exhibit attenuation flatness of 6.8 dB and attenuation range of 32–42 dB.