Slew rate/propagation delay selection circuit

Details Slew rate/propagation delay selection circuit Slew rate/propagation delay selection circuit

2000-03-10

2001-10-23

Tran, Toan (Department: 2816)

Miscellaneous active electrical nonlinear devices, circuits, and

Signal converting, shaping, or generating

Slope control of leading or trailing edge of rectangular or...

C327S170000, C327S134000

Reexamination Certificate

active

06307414

ABSTRACT:

FIELD OF THE INVENTION
The present invention relates to slew rate and propagation delay selection circuits generally and, more particularly, to an apparatus and method for selecting slew rate and propagation delay simultaneously.
BACKGROUND OF THE INVENTION
Slew rate control circuits for IO pads have been used to limit RLC oscillation of signals being driven off-chip and to limit simultaneously switching output (SSO) noise. However, conventional slew rate control circuits have a disadvantage of increasing propagation delay through an IO pad. Most IO pad designers are familiar with a trade off between slew rate control and propagation delay.
Slew rate control circuits are used in IO buffers of computer adapter cards. An adapter card designed for a PCI bus would have a particular propagation delay and slew rate control to meet the standard PCI specification. However, a PCIX bus specification (e.g., an enhanced version of the PCI bus) has a much more forgiving slew rate control requirement and much tighter propagation delay requirement than the standard PCI specification. An adapter card designed for use with the PCIX bus would need to provide less slew rate control, but much faster propagation delay. Since the PCIX bus is an enhanced version of the PCI bus, an adapter card that could operate on both buses would provide an advantage of easy migration from the PCI bus to the PCIX bus.
Conventional control circuits select between different propagation delays or different slew rates. However, the conventional circuits do not simultaneously select between different propagation delays and different slew rates.
A solution to select between different propagation delays and different slew rates simultaneously would be desirable.
SUMMARY OF THE INVENTION
The present invention concerns an apparatus comprising a first circuit and a second circuit. The first circuit may be configured to generate a first output signal having a predetermined slew rate and propagation delay in response to a first input signal and a control signal. The second circuit may be configured to generate a second output signal having a predetermined slew rate and propagation delay in response to a second input signal and said control signal.
The objects, features and advantages of the present invention include providing a method and/or apparatus that may (i) select between different propagation delays, (ii) select between different slew rates, (iii) provide a specific range of output slew rate and/or (iv) provide a specific range of propagation delay.


REFERENCES:
patent: 5355029 (1994-10-01), Houghton et al.
patent: 5986489 (1999-11-01), Raza et al.
patent: 6047346 (2000-04-01), Lau et al.

Affiliated with

Also associated with

Rating

Slew rate/propagation delay selection circuit does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Slew rate/propagation delay selection circuit, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Slew rate/propagation delay selection circuit will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2569771