Claims
- 1. A method of manufacturing an application specific integrated circuit having an output driver receiving a data signal via a predriver, for use with a selected circuit assembly comprising the steps:
- establishing an output driver impedance;
- determining a circuit ringing frequency value for a selected circuit portion of the circuit assembly; and
- establishing a predriver time constant greater than half the period of the ringing frequency, such that the predriver turns on slowly enough to dampen ringing.
- 2. The method of claim 1 wherein establishing a predriver time constant includes determining the capacitance of the output driver, and selecting a predriver resistance based on the capacitance.
- 3. The method of claim 1 wherein the predriver time constant is greater than the period of the ringing frequency.
- 4. The method of claim 1 including connecting the output driver to the selected circuit portion.
- 5. The method of claim 1 wherein determining the circuit ringing frequency includes determining an inductance and capacitance value for the selected circuit portion.
- 6. The method of claim 1 wherein establishing an output driver impedance includes substantially matching the output driver impedance to an impedance value associated with the selected circuit portion.
- 7. A method of designing an application specific integrated circuit for a circuit having a selected circuit portion with an impedance characteristic and a ringing frequency having a cycle period, the method comprising the steps:
- establishing an output driver size to substantially match the impedance characteristic of the selected circuit portion;
- determining the capacitance of the output driver;
- determining a predriver time constant greater than at least half of the cycle period; and
- establishing a predriver size based on the time constant and the output driver capacitance.
- 8. The method of claim 7 wherein the predriver time constant is at least the cycle period.
- 9. The method of claim 7 including determining an inductance and capacitance value for the selected circuit portion.
- 10. The method of claim 7 wherein establishing an output driver size includes substantially matching the output driver impedance to an impedance value associated with the selected circuit portion.
REFERENCE TO RELATED APPLICATION
This is a continuation-in-part of U.S. patent application Ser. No. 08/960,408, entitled "INTEGRATED CIRCUIT ASSEMBLY HAVING OUTPUT PADS WITH PROGRAMMABLE CHARACTERISTICS AND METHOD OF OPERATION," filed Oct. 29, 1997.
US Referenced Citations (25)
Foreign Referenced Citations (1)
Number |
Date |
Country |
0422391 |
Sep 1990 |
EPX |
Continuation in Parts (1)
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Number |
Date |
Country |
Parent |
960408 |
Oct 1997 |
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