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How to use Transmission Lines

• Special Case for BalancedDifFerential Signals Connect shields together

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Balanced = equal and opposite That is for AC components:

(+OUT) - -(-OUT)

Gdzie jest używane?

Standardy szeregowe

Serial ATA SATA1- 1.5 Gb/s; SATA2 - 3Gb/s FireWire HF.F.F. 1394 ) 400Mb/s (1600Mb/s)

Standardy równoległo/szeregowe

RocetlO - dołączenia układów scalonych 6.25Gb/s /linię PCI-Express 2.5Gb/s / linie - dla 161inii= 4GB/s ver2: 5Gb/s/linię;

HyperTransport: 200Mb/s - 26Gb/s / linie

Na podstawie: hitD://www.fbaa.aah.edu.Dl/ic/Linia Dluganoi

En.wikipedia.org:

LVDS is a differential sianalina system, meaning that it transmits Information as the difference between the voltages on a pair of wires; the two wire voltages are compared at the receiver. In a typical implementation, the transmitter injects a smali current, typically 3.5 mA. into one wire or the other, depending on the logie level to be sent. The current passes through a resistor of about 100 to 120 ohms (matched to the characteristic impedance of the cable) at the rcceiving end, then retums in the opposite direction along the other wire. From Ohm's law, the voltage difference across the resistor is therefore about 350 mV. The receiver senses the polarity of this voltage to determine the logie leveL This type of signalling is called a current Ioop.

The smali amplitudę of the signal and the tight electric- and magnetic-field coupling between the rwo wires reduces the amount of radiated electromagnetic noise (and power lost to conductor resistance).