It's a tightly integrated assembly of photonic components (lasers, modulators, photodetectors, drivers, TIAs) designed specifically for co-location with the ASIC. This integration significantly reduces the. CPO optical modules put optical and electronic parts together. This can cut power use by up to half. CPO technology lets more data fit in a small space. Whether its simple waveguides, splitters or crossings to propagate optical signal throughout the circuit with high fidelity and low loss, grating or edge couplers to efficiently couple light in and out of the circuit, or. Co-packaged optics is an innovative technology that enables the integration of optical components directly into a switch ASIC package (shown in the below figure) aimed at addressing next-generation bandwidth and power challenges. Refer to my post from almost three years ago to understand the internals of the PIC.
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