摘要 |
An adaptive output driver circuit utilizes an initial point matched impedance model to match the impedance of an output driver to the transmission line and produce an initial step voltage into the transmission line that is half of the desired final voltage. The driver output impedance is controlled by comparing a model of the actual working output stage to a target resistance given by the user. Control signals used to calibrate the impedance of the model to match the target are also used to adjust the working output buffer, so that when the impedance of the model matches the target, the impedance of the working buffer also matches the target impedance.
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