A Fast Startup 38.4-MHz Crystal Oscillator Achieving 99-nJ Startup Energy With Adaptive Chirping. - Abdolraouf Rahmani; Harikrishnan Ramiah; Ka-Meng Lei; Chee-Cheow Lim; Nai Shyan Lai; Pui-In Mak; Rui Paulo Martins (IEEE Access, 2024)