The invention discloses a
fast start crystal oscillator based on phase interpolation synchronous injection. The
fast start crystal oscillator comprises a digital module, a time-to-
digital converter, a
ring oscillator, a phase interpolation module, a first level shifter, a second level shifter, an
amplifier, a
crystal, a first load
capacitor, a second load
capacitor, a first switch, a second switch, a third switch, a fourth switch and a
comparator. According to the invention, the starting of the crystal is accelerated by performing intermittent energy injection on the crystal, in the injection interval, the time-to-
digital converter is used for detecting the
time difference between the injection phase and the crystal oscillation
signal, and the phase interpolation module is used for generating the correct injection phase, so that the rapid starting is realized. According to the invention, high-efficiency energy injection is realized, and stable increase of crystal
oscillation amplitude is ensured; the synchronous injection technology based on the phase interpolation module reduces the precision requirement of an energy injection
signal, guarantees the starting efficiency, reduces the design difficulty of an on-
chip injection source, and remarkably optimizes the yield of a
chip.