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公开(公告)号:US20110156725A1
公开(公告)日:2011-06-30
申请号:US12649590
申请日:2009-12-30
申请人: Leslie Carmichael , Michele Stein
发明人: Leslie Carmichael , Michele Stein
IPC分类号: G01R27/26
CPC分类号: G01R31/2824
摘要: Described herein are techniques for determining a board parasitic capacitance of a crystal oscillator circuit. A crystal's frequency is measured under load condition off-circuit. After coupling the crystal to the oscillator circuit, external capacitors may be adjusted to produce frequencies approximating the off-circuit measurement with upper and lower margins. Calculation of the load capacitor values at the exact frequency measured off-circuit allows for derivation of the board parasitic capacitance by subtracting the calculated capacitor values from the original total load value used in the off-circuit measurement.
摘要翻译: 这里描述了用于确定晶体振荡器电路的板寄生电容的技术。 晶体的频率是在负载条件下测量的。 在将晶体耦合到振荡器电路之后,可以调整外部电容器以产生接近具有上部和下部边缘的非线性测量的频率。 在测得的非正常频率下的精确频率下的负载电容值的计算允许通过从在电路测量中使用的原始总负载值减去计算的电容值来推导电路板的寄生电容。
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公开(公告)号:US08299777B2
公开(公告)日:2012-10-30
申请号:US12649590
申请日:2009-12-30
申请人: Leslie Carmichael , Michele Stein
发明人: Leslie Carmichael , Michele Stein
CPC分类号: G01R31/2824
摘要: Described herein are techniques for determining a board parasitic capacitance of a crystal oscillator circuit. A crystal's frequency is measured under load condition off-circuit. After coupling the crystal to the oscillator circuit, external capacitors may be adjusted to produce frequencies approximating the off-circuit measurement with upper and lower margins. Calculation of the load capacitor values at the exact frequency measured off-circuit allows for derivation of the board parasitic capacitance by subtracting the calculated capacitor values from the original total load value used in the off-circuit measurement.
摘要翻译: 这里描述了用于确定晶体振荡器电路的板寄生电容的技术。 晶体的频率是在负载条件下测量的。 在将晶体耦合到振荡器电路之后,可以调整外部电容器以产生接近具有上部和下部边缘的非线性测量的频率。 在测得的非正常频率下的精确频率下的负载电容值的计算允许通过从在电路测量中使用的原始总负载值减去计算的电容值来推导电路板的寄生电容。
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