BCK Technology Specialized for Peripheral Applications


M31 provides customers with not only a standard USB PHY solution, but also a unique BCK (Built-in-Clock, i.e., crystal-free) function to eliminate the need of external crystal oscillator. The IP processes background calibration during USB data transfer to ensure frequency accuracy. The USB IP with BCK can meet the USB-IF compliance specification and possess the same electrical performances as the standard USB IP.


  • Worldwide smallest USB 3.2 Gen1X1 BCK PHY IP (<0.36mm²)
  • Fully compliant with Universal Serial Bus USB 3.2 Gen1X1, USB 2.0 and USB 1.1 electrical specifications
  • Supports clock outputs from internal BCK module
  • Real-time calibrations to assure the frequency accuracy
  • Data UI (unit interval) is well-controlled within ±500ppm during data transfer
  • Concise and explicit design structure to ease the IP integration
  • Available in 40nm, 55nm, and 110nm logic process

The BCK Series USB PHY still exhibit very good jitter control even if it’s without the external clock sources