AllenD
Member level 5
Hi Team
I am trying to design 8 phases non overlapping clocks with a pair of non_overlapping "envelope clocks" as depicted in the attached picture
The left side of the picture: The first 8 signals are the non-overlapping clocks and the last 2 (white and brown) clock signals are the envelope clocks. In other words, the envolope clock (white) should be "1" before the first clock phase(green) is "1" and remain the level after last clock phase (yellow) is one. However, it also have to be "0" before the next round of 8 phases.
The right side of the picture: The illustration of such a relationship.
All of the nonoverlapping is achieved by cross-coupled NOR with 2 inverters. The 8 phases non-overlapping clocks are achieved by johns counter
and the envelope signal is by a frequency divider of one if the flipflops as in the pic
BUT THE PHASE/DELAY RELATIONSHIP BETWEEN 2 ENVELOPE SIGNALS AND 8 PHASES CLOCKS IS BY HAND TUNED INVERTER DELAY UNITS.
Question:
Unlike the non-overlapping-ness is secured by the topology, the phase relationship between the 2 envelope signals and 8 phases clock is affected by process variations. In other words, one of the envelope signal may fail to cover the last clock phase or may cover the first clock phase of the next 8 phases round.
Is there a topology that I can use to secure the phase relationship between the 2 envelope signals and 8 phases clock as I desired?
Thank you!
Allen
I am trying to design 8 phases non overlapping clocks with a pair of non_overlapping "envelope clocks" as depicted in the attached picture
The left side of the picture: The first 8 signals are the non-overlapping clocks and the last 2 (white and brown) clock signals are the envelope clocks. In other words, the envolope clock (white) should be "1" before the first clock phase(green) is "1" and remain the level after last clock phase (yellow) is one. However, it also have to be "0" before the next round of 8 phases.
The right side of the picture: The illustration of such a relationship.
All of the nonoverlapping is achieved by cross-coupled NOR with 2 inverters. The 8 phases non-overlapping clocks are achieved by johns counter
and the envelope signal is by a frequency divider of one if the flipflops as in the pic
BUT THE PHASE/DELAY RELATIONSHIP BETWEEN 2 ENVELOPE SIGNALS AND 8 PHASES CLOCKS IS BY HAND TUNED INVERTER DELAY UNITS.
Question:
Unlike the non-overlapping-ness is secured by the topology, the phase relationship between the 2 envelope signals and 8 phases clock is affected by process variations. In other words, one of the envelope signal may fail to cover the last clock phase or may cover the first clock phase of the next 8 phases round.
Is there a topology that I can use to secure the phase relationship between the 2 envelope signals and 8 phases clock as I desired?
Thank you!
Allen