View All num of num Add Photos Scintera Networks www.scinteranetworks.com Unclaimed Profile Overview Reviews Salaries Interviews Jobs Photos Benefits 4 Reviews 20 Salaries 3 Interviews Follow Add Review or Salary Follow Add Review or Salary Interview Question Analog Design Engineering Interview Sunnyvale, CA Scintera Networks Why do we need the "DOWN" pulse in Hogge detector? Can we get by not using it? Tags: hogge phase detectors, cdr See more , See less 8 Answer Add Tags Answer Interview Answer 1 Answer ▲ 0 ▼ My answer was we don't need to use it. But we have to change our filter structure. Using UP and DOWN fit well to charge pump and passive RC filter topology. Since DOWN is always 50% duty cycle when there is data transition, it acts as a reference. However, if we took the UP pulse alone, feed it to an active filter with one pole ar zero and one zero at a non- zero frequency we preserve the loop dynamics. Interview Candidate on Jul 6, 2010 Interviews > Analog Design Engineering > Scintera Networks Add Answers or Comments To comment on this, Sign In or Sign Up.