Suited for applications with 400–1,100 nm wavelength, Silicon Avalanche photodiodes (Si APDs) are optical detectors that come in hermetic TO Cans and feature internal gain mechanism, rise times as low as 300 psec, and high sensitivity in NIR region. Optical sensitivity peak is optimized for 800 or 905 nm, and standard versions are available with 200, 500, and 800 µm active diameter. Additional characteristics include 80–200 V breakdown voltage and frequency response up to 1 GHz.