A 1.7-GHz 1.5-mW digitally-controlled FBAR oscillator with 0.03-ppb resolution. - Hiroyuki Ito; Hasnain Lakdawala; Ashoke Ravi; Stefano Pellerano; Rick Ruby; Krishnamurthy Soumyanath; Kazuya Masu (ESSCIRC, 2008)