Method of evaluating quality of crystal unit
AssigneeSuwadenshi Co., Ltd.
InventorHajime Ushiyama
Life of this patent
Estimating the term…
Abstract
A method of evaluating quality of a crystal unit, capable of performing quantitative measurement of an actual operation of a crystal unit which is to be oscillated in an actual oscillator to ensure an accurate quality evaluation, is provided. The method includes increasing a DC input voltage of a crystal oscillator, the crystal oscillator having at least one AGC amplifier whose amplification rate varies depending on the DC input voltage and having a crystal unit connected thereto, measuring a maximum value of the DC input voltage at a start of oscillation of the crystal oscillator, and evaluating quality of the crystal unit by the measured maximum value.
Claims20
A method of evaluating quality of a crystal unit, said method comprising:
- increasing a DC input voltage of a crystal oscillator, the crystal oscillator having at least one AGC amplifier whose amplification rate varies depending on the DC input voltage and having a crystal unit connected thereto;
- measuring a maximum value of the DC input voltage at a start of oscillation of the crystal oscillator;
- and
- evaluating the quality of the crystal unit by the measured maximum value of the DC input voltage.
A method of evaluating quality of a crystal unit, said method comprising:
- setting a DC input voltage of a crystal oscillator at a specific voltage value for evaluation, the crystal oscillator having at least one AGC amplifier whose amplification rate varies depending on the DC input voltage and having a crystal unit connected thereto;
- observing whether the crystal oscillator starts oscillation or not with the DC input voltage set at the specific voltage value;
- and
- evaluating the quality of the crystal unit by presence or absence of start of oscillation.
A method of evaluating quality of a crystal unit, said method comprising:
- setting a driving power of a crystal oscillator at a specific power value for evaluation, the crystal oscillator having at least one AGC amplifier whose amplification rate varies depending on a DC input voltage and having a crystal unit connected thereto;
- measuring, after the crystal oscillator enters a stable oscillation state, at least one of the DC input voltage and an oscillation frequency at the specific power value;
- and
- evaluating the quality of the crystal unit by the measured value.
A method of evaluating quality of a crystal unit, said method comprising:
- setting a driving power of a crystal oscillator at a plurality of specific power values for evaluation, the crystal oscillator having at least one AGC amplifier whose amplification rate varies depending on a DC input voltage and having a crystal unit connected thereto;
- measuring, after the crystal oscillator enters a stable oscillation state, at least one of the DC input voltage and an oscillation frequency at each of the plurality of specific power values;
- and
- evaluating the quality of the crystal unit by the measured values.
A method of evaluating quality of a crystal unit, said method comprising:
- changing a driving power of a crystal oscillator continuously, the crystal oscillator having at least one AGC amplifier whose amplification rate varies depending on a DC input voltage and having a crystal unit connected thereto;
- measuring, after the crystal oscillator enters a stable oscillation state, at least one of the DC input voltage and an oscillation frequency continuously;
- and
- evaluating the quality of the crystal unit by the continuously measured values of the at least one of the DC input voltage and the oscillation frequency.
Dependencies are inferred from the claim text.