That's orthogonal to differential or single ended, but typically the transmit side uses some form of current steering; it just goes well with it. E.g. PCIe tra

That's orthogonal to differential or single ended, but typically the transmit side uses some form of current steering; it just goes well with it. E.g. PCIe transmitters are HSCL, which is a form of current steering that gives the receiver exactly the voltages it needs to see at nominal currents and termination values.