Transmission line driver circuit for adaptively correcting impedance matching

Abstract

The invention provides a transmission line driver circuit for adaptively correcting impedance matching. The transmission line driver circuit comprises a transmission line driving amplifier having a first transmission end and a second transmission end, a first signal node, a second signal node, a first adjustable resistor disposed between the first transmission end and the first signal node, a second adjustable resistor disposed between the second transmission end and the second signal node, an internal node, a first divider resistor disposed between the first signal node and the internal node, a second divider resistor disposed between the second signal node and the internal node, a comparison circuit used for comparing a reference voltage and the partial voltage on the internal node to generate a comparison signal, and an adjustment circuit used for adjusting the resistance value of one of the first adjustable resistor and the second adjustable resistor according to the comparison signal to enable the transmission line driver circuit and an equivalent load circuit achieve impedance matching.

Description

technical field [0001] The invention relates to the technical field of transmission line driving circuits, in particular to a transmission line driving circuit for adaptively correcting impedance matching. Background technique [0002] In order to transmit signals and energy efficiently, ideally, the output circuit and the input circuit should work in an impedance matching state. That is, the internal resistance of the output circuit should be equal to the input impedance of the output circuit, and the output impedance of the output circuit should be equal to the impedance of the input circuit (also called load). Maximum power transfer is achieved when the impedances of both the output and input circuits match each other. On the contrary, when the impedances of the output circuit and the input circuit do not match, not only the maximum power transmission cannot be obtained, but also the circuit may be damaged. [0003] For example, when the impedances of the output circuit...

AI Technical Summary

Problems solved by technology

Conversely, when the impedances of the output circuit and the input circuit do not match, not only will the maximum power transmission not be obtained, but the circuit may also be damaged.

[0003] For example, when the impedance of the output circuit and the input circuit do not match, the differential output current of the output circuit will be asymmetrical, which will lead to the problem of electromagnetic interference (EMI)

In addition, when the impedance of the output circuit and the input circuit do not match, the return loss (ReturnLoss) of the system will also increase

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