Isixhobo yimodyuli ye-silicon avalanche photodiode eneeyunithi ezine ezifanayo, kunye nesekethe eyakhelwe-ngaphakathi ye-preamplifier, enokuthi ikhulise isignali yangoku ebuthathaka kwaye iyiguqule ibe yimveliso yesignali yombane, ukuqonda inkqubo yokuguqulwa "ye-optical-electrical-signal amplification".