FUNDAMENTAL WAVE/OVERTONE CRYSTAL OSCILLATOR

• Main Authors: AKAIKE KAZUO, MOHD HAFIDZ, HOSHIGAMI HIROSHI
• Format: Patent
• Language: English
• Published: 08.09.2011
• Subjects: BASIC ELECTRONIC CIRCUITRY; ELECTRICITY; GENERATION OF NOISE BY SUCH CIRCUITS; GENERATION OF OSCILLATIONS, DIRECTLY OR BY FREQUENCY-CHANGING,BY CIRCUITS EMPLOYING ACTIVE ELEMENTS WHICH OPERATE IN ANON-SWITCHING MANNER

PROBLEM TO BE SOLVED: To provide a fundamental wave/overtone crystal oscillator capable of obtaining fundamental wave oscillation and overtone oscillation by one crystal oscillator and optimizing an excitation current depending on the fundamental wave oscillation and the overtone oscillation. SOLUTION: The fundamental wave/overtone crystal oscillator includes the crystal oscillator 1 capable of oscillating a fundamental wave or an overtone, and an oscillation circuit 30 that amplifies an excitation current from the crystal oscillator 1 and outputs an oscillatory frequency. A capacitor Cf and a capacitor Co are connected in parallel with the base of a transistor Tr31 in the oscillation circuit 30 and connected with an emitter, and a capacitor C32 and a resistor R32 are connected in parallel with the emitter. A switch SW31 is provided so as to connect or disconnect the capacitor Cf to/from the circuit by a switching signal, and the switch SW31 is operated so as to be turned on when oscillating at fundamental waves and turned off when oscillating at overtones. COPYRIGHT: (C)2011,JPO&INPIT