A 6–12 GHz Wideband Low-Noise Amplifier With 0.8–1.5 dB NF and ±0.75 dB Ripple Enabled by the Capacitor Assisting Triple-Winding Transformer
Tenghao Zou, Hao Xu, Yizhuo Wang, Weitian Liu, T. T. Han, Mi Tian, Weiqiang Zhu, Na Yan
Abstract
This paper presents a wideband 6-12GHz two-stage low noise amplifier (LNA) that utilizes capacitor assisting triple-winding transformer in the inter-stage matching network. The electric coupling introduced by the assisting capacitor expands the design space by allowing independent control of each effective coupling strength of the three coupled inductors. The equivalent negative resistor enhanced by this capacitor improves the quality factor of the inter-stage network at high frequencies, which further improves the overall design trade-off among gain, bandwidth and noise figure. Fabricated in a 130nm SOI CMOS process, the LNA achieves a remarkable 0.8-1.5dB NF, <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$< $ </tex-math></inline-formula> -14dB S11, <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$< $ </tex-math></inline-formula> -8dB S22, -11.8dBm IP <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$_{\mathbf{1dB}}$ </tex-math></inline-formula> and 21.8-23.3dB power gain across the 6-12GHz passband with ±0.75dB ripple while drawing 20mA from a 3.3V supply.