Class-C architecture for cross-coupled FBAR oscillator to further improve phase noise

• Published in: IEICE Electronics Express
• Main Author: Enche Ab Rahim S.A.; Pokharel R.K.
• Format: Article
• Language: English
• Published: Institute of Electronics Information Communication Engineers 2017
• Online Access: https://www.scopus.com/inward/record.uri?eid=2-s2.0-85015419698&doi=10.1587%2felex.14.20170056&partnerID=40&md5=644662d0e880b2e3fe7a910c5081cf9f

In this letter, a class-C architecture for an oscillator employing film bulk acoustic resonator (FBAR) is presented to improve the phase noise significantly in 1/f3 region. The advantages offers by class-C operation are exploited in order to reduce the noise contributed by the current-source transistor in cross-coupled topology. An adaptive biasing circuit is used in order to ensure the oscillation start-up. The post-layout simulation incorporating all parasitic and representing FBAR by modified Butterworth Van Dyke (MBVD) model illustrates the phase noise improvement by 17 dBc/Hz at 100 kHz offset of a 1.9 GHz carrier compared to the FBAR based cross-coupled topology presented by the authors [1]. © IEICE 2017.