Cr type oscillator

Abstract

Abstract PURPOSE:To obtain an oscillation signal having a nearly stable oscillating frequency by generating a control signal when the oscillation frequency is discriminated as outside of a permissible frequency so as to select and switch plural time constant elements in a way that the oscillating frequency is converged into the permissible frequency. CONSTITUTION:A CR oscillation circuit 11 has plural time constant elements and the frequency of the oscillator output is changed by connecting selectively the plural time constant elements respectively so as to change the time constant. An oscillation signal phi3 outputted from the CR oscillating circuit 11 is fed to an oscillating frequency discriminating circuit 12. The oscillating frequency discriminating circuit 12 receives a reference frequency signal phia outputted from a reference frequency signal generating circuit together with the said oscillating signal phi3 and compares each frequency of the two signals phia and phis to discriminate whether an oscillation frequency fosc of the oscillation signal phis is within the permissible frequency range to be preset, more than the permissible frequency or less than the permissible frequency and a discrimination signal in response to the result of each discrimination is generated and outputted. The discrimination signal is fed to a control signal generating circuit 13.

Inventors

• 👤 Akira Yamaguchi
• 👤 明 山口
• 👤 Koichi Sato
• 👤 晃一 佐藤

Bibliographic Details