From Ohm's law, the voltage difference across the resistor is therefore about 350 mV.
The current passes through a termination resistor of about 100 to 120 ohms (matched to the cable's characteristic impedance to reduce reflections) at the receiving end, and then returns in the opposite direction via the other wire. In a typical implementation, the transmitter injects a constant current of 3.5 mA into the wires, with the direction of current determining the digital logic level. LVDS is a differential signaling 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.
- 5 LVDS for very high data-throughput applicationsĭifferential vs.
- 4 LVDS transmission with 8b/10b encoding.
- 3 Comparing serial and parallel data transmission.
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The typical applications are high-speed video, graphics, video camera data transfers, and general purpose computer buses.Įarly on, the notebook computer and LCD display vendors commonly used the term LVDS instead of FPD-Link when referring to their protocol, and the term LVDS has mistakenly become synonymous with Flat Panel Display Link in the video-display engineering vocabulary. LVDS was introduced in 1994, and has become popular in products such as LCD-TVs, in-car entertainment systems, industrial cameras and machine vision, notebook and tablet computers, and communications systems. LVDS is a physical layer specification only many data communication standards and applications use it and add a data link layer as defined in the OSI model on top of it. LVDS operates at low power and can run at very high speeds using inexpensive twisted-pair copper cables. Low-voltage differential signaling ( LVDS), also known as TIA/EIA-644, is a technical standard that specifies electrical characteristics of a differential, serial signaling standard. Basic LVDS circuit operation showing current flowing in a loop back to the driver and the resulting lower radiated emission (EMI) due to field coupling within the differential pair