An ultra broadband DC-12 GHz 4-bit GaAs monolithic digital attenuator

A novel FET-based switchable attenuator circuit has been developed which can easily be realized in MMIC (monolithic microwave integrated circuit) form. The resulting 4-bit 1 dB step attenuator has achieved the broadest bandwidth (DC-12 GHz) yet reported. Impressive attenuation accuracy has been preserved over the 15 dB attenuation range and full 12 GHz bandwidth while the reference insertion loss at 12 GHz is only 3.5 dB. The die size of 1.2*0.8 mm (48*32 mils) represents a significant reduction in size and cost over all prior realizations of this function.<>