A 6-bit Step Attenuator With a Single Positive Adjustable Bias Using Source Floating Technique in 0.15 μ m GaAs Technology

This study presents a 6-bit step attenuator in 0.15 μm GaAs technology. The fabricated attenuator's minimum and maximum step attenuation are 0.5 dB and 16 dB, respectively. On attenuator switches, the source floating bias method is utilized to enable operation at voltages greater than the transistors' threshold voltage. Measurement results show that from 5.35 GHz to 11.25 GHz, the RMS amplitude error is less than 1.7 dB and the RMS phase error is between 9.9 and 2.92 degrees using a bias control of 5 V. For bias and control voltages of 5 V, 3.3 V, and 1.8 V, the chip's input P1dB is greater than 27 dBm. The die area is 1.95×1.89 mm2.