A 233-GHz low noise amplifier with 22.5dB gain in 0.13μm SiGe

Abstract

A low noise amplifier (LNA) design for 230GHz applications in an advanced SiGe heterojunction bipolar transistor technology is presented. The circuit consists of a four-stage pseudo-differential cascode topology. It was implemented in a commercially available SiGe BiCMOS technology with fT/fmax of 300/450GHz. By employing positive feedback for unilateralization the small-signal gain is increased, enabling circuit operation in high frequency bands and improved efficiency. The amplifier has measured 22.5dB gain at 233GHz with a 3dB bandwidth of 10GHz and a simulated noise figure of 12.5dB. The low noise amplifier draws only 17mA from a 4V supply.