Self alignment system for complement clocks

1. A self alignment system for complement clock signals, the self alignment system comprising:

a first delay circuit operable to delay a first clock signal; and

a second delay circuit operable to delay a second clock signal that is out of phase with the first clock signal,

wherein the delay of the first and second clock signals is independently variable as a function of the relationship of the first clock signal to the second clock signal, and

wherein each of the first and second delay circuits includes a variable resistance and a capacitor coupled between a plurality of inverters.

2. The self alignment system of claim 1 , wherein delay with the first delay circuit is variable as a function of the second clock signal and delay with the second delay circuit is variable as a function of the first clock signal.

3. The self alignment system of claim 1 , wherein independent delay of the first and second clock signals are variable during transitions of the first and second clock signals between clock states.

4. The self alignment system of claim 1 , wherein the first and second delay circuits are operable to adjust the timing of the respective first and second clock signals to maintain the first clock signal phase shifted by about 180 degrees from the second clock signal.

5. The self alignment system of claim 1 , wherein the first and second delay circuits are operable to adjust the timing of the respective first and second clock signals to intersect during transitions of the first and second clock signals between clock states that are a high voltage state and a low voltage state.

6. The self alignment system of claim 1 , wherein the first and second delay circuits are operable so adjust the timing of the respective first and second clock signals to cross at the corner of a transition period.

7. The self alignment system of claim 1 , wherein the first and second delay circuits are operable to adjust the timing of transitions of the respective first and second clock signals to intersect at about 50% of the peak to peak voltage of the first and second clock signals.

8. The self alignment system of claim 1 , wherein the first and second delay circuits are operable to selectively adjust the timing of the respective first and second clock signals twice during each cycle of the first and second clock signals.

9. A self alignment system for complement clock signals, the self alignment system comprising:

a first variable resistance operable to conduct a first clock signal; and

a second variable resistance operable to conduct a second clock signal,

wherein the first clock signal is operable to vary the resistance of the second variable resistance, and the second clock signal is operable to vary the resistance of the first variable resistance to selectively adjust delay of the respective first and second clock signals, and

wherein the first and second variable resistances each include a first transfer gate and a second transfer gate.

10. The self alignment system of claim 9 , wherein the first and second variable resistances each comprise a plurality of paralleled transistors.

11. The self alignment system of claim 9 , wherein resistance of the first and second variable resistances are respectively increased to increase the delay of the respective first and second clock signals.

12. The self alignment system of claim 9 , wherein resistance of the first and second variable resistances is respectively increased during a transition between clock states of the respective first and second clock signals to increase respective delay.

13. The self alignment system of claim 9 , wherein the first and second variable resistances are increased outside of a transition of the first and second clock signals between clock states to avoid increasing delay.

14. The self alignment system of claim 9 , wherein the first and second variable resistances each include a plurality of transistors, the resistance of the first and second variable resistances independently variable as a function of transition of the transistors between an activated and a deactivated state.

15. The self alignment system of claim 9 , further comprising a plurality of inverter chains, wherein the first and second variable resistances are each coupled with one of the inverter chains.

16. A method of aligning complement clock signals, the method comprising:

applying a first complement clock signal to a first variable resistance that is operable to conduct the first complement clock signal;

applying a second complement clock signal to a second variable resistance that is operable to conduct the second complement clock signal;

wherein the first and second variable resistances each include a first transfer gate and a second transfer gate;

increasing the first variable resistance during a transition of the first complement clock signal when the first complement clock signal is leading the second complement clock signal; and

increasing the second variable resistance during a transition of the second complement clock signal when the first complement clock signal is lagging the second complement clock signal.

17. The method of claim 16 , wherein increasing the first variable resistance comprises controlling the first variable resistance with the second complement clock signal.

18. The method of claim 16 , wherein increasing the second variable resistance comprises controlling the second variable resistance with the first complement clock signal.

19. The method of claim 16 , wherein increasing one of the first and second variable resistances comprises activating the first transfer gate and deactivating the second transfer gate included in each of the first and second variable resistances at the same time.

20. The method of claim 16 , wherein increasing one of the first and second variable resistances comprises turning a first transistor off while turning a second transistor on.

21. The method of claim 16 , further comprising increasing the second variable resistance outside of the transition period of the second complement clock signal when the first complement clock signal is leading the second complement clock signal.

22. The method of claim 16 , further comprising increasing the first variable resistance outside of the transition period of the first complement clock signal when the first complement clock signal is lagging the second complement clock signal.

23. The self alignment system of claim 1 , wherein the delay of the first clock signal is variable as a function of the second clock signal and the delay of the second clock signal is variable as a function of the first clock signal.

24. The self alignment system of claim 1 , wherein the delay of the first clock signal is independently variable with respect to the delay of the second clock signals.

25. The self alignment system of claim 1 , wherein the delay of each of the first and second clock signals is variable to adjust a desired phase shift between the first and second clock signals.

26. The self alignment system of claim 1 , wherein the delay of the first clock signal is variable as a function of the second clock signal and the delay of the second clock signal is variable as a function of the first clock signal, and the delay of the first and second clock signals are variable with respect to each other to adjust a desired phase shift between the first and second clock signals.

27. The self alignment system of claim 9 , wherein the delay of the first and second clock signals is selectively adjustable to adjust a phase shift between the first and second clock signals.

28. The method of claim 16 , wherein the first variable resistance and the second variable resistance are increased to adjust a phase shift between the first and second clock signals.