Silicon-photonics based high volume manufacturable lasers are playing an increasingly important role in optical communication and sensing due to their low-cost, high performance, and seamless integration with other silicon photonics components. Here we demonstrate a silicon-photonics based widely tunable laser with integrated semiconductor optical amplifier (SOA) and wavelength reference on a high-volume, 300-mm III-V/Si integration platform. The laser shows a tuning range >50 nm with side-mode suppression ratio >55 dB, Lorentzian linewidth