Four‐segment oscillator circuit for piezoelectric sensing devices

Abstract

Novel circuit design is proposed for a low‐frequency quartz crystal oscillator circuit that consists of four segments. The characteristics of the negative resistance in a low‐frequency Complementary Metal Oxide Semiconductor (CMOS)‐inverter quartz oscillator were reviewed for the two modes of SC (stress‐compensated) cut mode and the overtone of low‐frequency mode; separation of two modes and suppression of overtone oscillation were demonstrated successfully. Experimental results and an estimate of the absolute value of the negative resistance are presented for the four‐segment oscillator circuit and the conventional Colpitts circuit and two new types of oscillator circuits. © 2011 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.

Suppression of overtone oscillation and low‐current operation using novel‐design scheme for quartz crystal oscillators

“…In this case, the stabilization is realized by the gain suppression. The gain is controlled by R 3 and R 4 in the power line through the negative feedback [5]. These resistors suppress the drive current and realize the stabilization of gain.…”

Control and monitoring of the quartz crystal current in the quartz crystal oscillator

“…1. CMOS-inverter oscillator circuit: (a) new oscillator circuit with grounded terminal [8][9][10][11][12][13], (b) the Colpitts oscillator [4][5][6][7] OCXO, the high stability of the oscillation frequency needs the suppression of the excitation level. Simpler method, such as the limiter system is also known.…”

“…In these applications, the oscillator is realized by the elaborated circuits designed with bipolar transistors. Simple is the best: in this work, new oscillator circuit is realized using a single gate CMOS inverter and simpler limiter circuit [8][9][10][11][12][13]. Figure 2 shows a simplified equivalent circuit of the quartz crystal oscillator with grounded terminal, shown in Fig.…”