Pros Cons ·Advantages Loop bandwidth is adaptively controlled Residual fractional error is reduced and VCO clock is counted directly Lower phase noise due to the 4/4.5 prescaler Measured low phase noise,low phase error and fast locking time ·Disadvantages >The 4/4.5 prescaler leads to a little bit higher power The fractional spur is high when fractional modulus is close to 0 or 1 2009 IEEE International Solid-State Circuits Conference 2009 IEEE© 2009 IEEE International Solid-State Circuits Conference © 2009 IEEE 4 Pros & Cons • Advantages ¾ Loop bandwidth is adaptively controlled ¾ Residual fractional error is reduced and VCO clock is counted directly ¾ Lower phase noise due to the 4/4.5 prescaler ¾ Measured low phase noise, low phase error and fast locking time • Disadvantages ¾ The 4/4.5 prescaler leads to a little bit higher power ¾ The fractional spur is high when fractional modulus is close to 0 or 1