A method to lower VCO phase noise by using HBT darlington pair
Paper in proceedings, 2012

The paper presents a novel method to enhance tank voltage swing in LC VCOs design using bipolar transistor. The method is successfully demonstrated in an InGaP/GaAs HBT MMIC process. A gm-boosted VCO and a modified version, using Darlington-pair transistors, are compared. The latter exhibits lower phase noise, increased tuning range, and less variation in output power. The gm-boosted VCO has tuning range of 22.8% centered at 5.7GHz and phase noise ranging from 103 to 95 dBc/Hz at offset frequency of 100kHz. The modified version using Darlington pair has tuning range of 26% centered at 5.9 GHz and phase noise ranging from 103.5 to 98.5 dBc/Hz at offset frequency of 100kHz.

Phase-noise

MMIC

VCO

Darlington pair

HBT

Author

Szhau Lai

GigaHertz Centre

Chalmers, Microtechnology and Nanoscience (MC2), Microwave Electronics

M. Bao

GigaHertz Centre

Dan Kuylenstierna

Chalmers, Microtechnology and Nanoscience (MC2), Microwave Electronics

GigaHertz Centre

Herbert Zirath

GigaHertz Centre

Chalmers, Microtechnology and Nanoscience (MC2), Microwave Electronics

IEEE MTT-S International Microwave Symposium Digest

0149645X (ISSN)

6259421

Subject Categories

Electrical Engineering, Electronic Engineering, Information Engineering

DOI

10.1109/MWSYM.2012.6259421

ISBN

978-146731087-1

More information

Latest update

2/7/2019 1