Who makes drivers and TIAs for AI data centers

In an optical transceiver the DSP does the digital work; these are the analogue chips either side of it. The driver takes the electrical signal and swings it hard enough to modulate the laser, and the transimpedance amplifier takes the very small current out of the photodetector and turns it into a usable voltage. They sit physically closest to the optics, and they set how clean the signal is before the DSP ever sees it. Because they are analogue and close to the light, they scale differently from the DSP. Each jump in per-lane rate demands more bandwidth and better linearity from the driver and TIA, and the design margin comes from process and layout skill rather than from a node shrink. That is why this remains a specialist analogue business rather than being absorbed into the DSP. AI networking is what drives the volume: a large GPU cluster needs an enormous number of optical lanes, and every one of them carries a driver and a TIA at each end. Co-packaged optics changes the packaging of these parts but does not remove them. What to look for is which lane rates a supplier has silicon shipping at, whether it sells into module makers or into the switch vendors directly, and how exposed it is to a single module customer — this is a component sale into a competitive module market, so pricing pressure travels straight through.