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navigation_gps:gps_antenna_signal_splitter [2016/12/17 11:01] kjeld |
navigation_gps:gps_antenna_signal_splitter [2016/12/19 15:25] (current) |
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- | In the real world capacitors are not ideal however, the construction and external leads add inductive and resistive components. This causes a number of complications, one of them being that capacitors have a series self-resonant frequency (SRF) due to parasitic inductance. ((http://www.ti.com/lit/an/sloa069/sloa069.pdf)). | + | In the real world capacitors are not ideal however, the construction and external leads add inductive and resistive components. This causes a number of complications, one of them being that capacitors have a series self-resonant frequency (SRF) due to parasitic inductance((http://www.ti.com/lit/an/sloa069/sloa069.pdf)). |

- | * At frequencies below the SRF the impedance is primarily capacitive. | + | * At frequencies below the SRF the impedance is primarily capacitive. |

- | * At the SRF the capacitive and inductive components cancels each other leaving only the resistive component which is typically stated in the data sheets as Equivalent Series Resistor (ESR). | + | * At the SRF the capacitive and inductive components cancels each other leaving only the resistive component which is typically stated in the data sheets as Equivalent Series Resistor (ESR). |

- | * Above SRF the impedance is primarily inductive. | + | * Above SRF the impedance is primarily inductive. |

In theory the lowest resistance at a working frequency would be obtained by selecting a capacitor with a SRF at this frequency. But since capacitor values are not accurate, SRF should be higher than the working frequency to avoid inductive properties. | In theory the lowest resistance at a working frequency would be obtained by selecting a capacitor with a SRF at this frequency. But since capacitor values are not accurate, SRF should be higher than the working frequency to avoid inductive properties. |