摘要 |
Method and apparatus for a bi-direction interface and communication link are described. More particularly, an input/output block is formed with a digitally controlled impedance output driver output coupled at an input/output node to an input terminal of a differential amplifier. Another terminal of the differential amplifier is used for inputting a reference voltage. As the digitally controlled impedance output buffer may be adjusted for impedance matching with transmission line impedance, no parallel terminating resistance is needed. Accordingly, two such input/output blocks may be coupled to form a bi-directional communication link with the advantage of an absence of parallel termination resistance at inputs to such input/output blocks.
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