Three‐stage GaN‐on‐SiC medium‐power LNA exploiting a current‐reuse architecture

Abstract

A recently presented implementation of the current‐reuse concept, specifically devised for microwave cascaded single‐ended amplifiers, is applied to the design of a three‐stage medium‐power low‐noise amplifier (LNA) operating in X‐band. The LNA is realized on a GaN‐on‐SiC 0.25 µm technology supplied by Leonardo S.p.A.'s internal foundry and achieves a transducer gain (GT) of 24 dB, a noise figure (NF) better than 2.5 dB and an output power at 1 dB gain compression (Pout,1dB) higher than 20 dBm over the whole X‐band. The first two stages of the LNA are stacked and share the same current while requiring, as a pair, a doubled external supply voltage, which corresponds to that of the third, medium‐power stage. The versatility of the adopted current‐reuse concept is exemplified by the fact that the two low‐noise stages are initially designed in a conventional single‐ended topology: only in a second step are they converted into a current‐sharing stage pair with no significant effect on RF performance. Nonconventional approaches to low‐noise design and small‐signal stability analysis developed by the Authors and adopted in this design are referred to the Reader.

An X-Band State Adjustable Low Noise Amplifier Using Current Reuse Technique

“…Ref. [11], based on GaN-on-SiC technology, designs a medium-power LNA in which the first two stages adopt current reuse architecture and the final stage adopt a CS structure.…”

Design ofGaN‐basedX‐band LNAsto achieve sub‐1.2 dBnoise figure

“…Vignesh et al 6 have proposed quasi circulator LNA with the current reused technique to achieve optimized NF of less than 1.4 dB in X-band using 0.065 μm CMOS technology. Colangeli et al 11 proposed three-stage LNA using 0.25 μm GaN-on-SiC technology by exploiting the same current-reuse architecture. The impedance between the base-collector terminals of common-emitter HBT is considered by Çalıs ¸kan et al 7 to achieve sub-1 dB NF.…”

A scalable electrothermal model using a three‐dimensional thermal analysis model forGaN‐on‐diamondhigh‐electron‐mobility transistors

“…GaN high‐electron‐mobility transistors (HEMTs) are technologically attractive because they can operate at high power density and frequency, which has led to their wide use in high‐power solid‐state microwave amplifiers 1 . However, for the sake of completeness, they should underline that nowadays this technology is attracting some attention also for high‐frequency low‐noise applications 2‐4 . Microwave GaN HEMTs on silicon carbide (SiC) and silicon substrates have become mature technologies, and commercial foundries now produce devices that operate up to 110 GHz.…”