Title :
Near-linear CMOS I/O driver with less sensitivity to process, voltage, and temperature variations
Author :
Esch, Gerald, Jr. ; Chen, Tom
Author_Institution :
Agilent Technol., Inc., Fort Collins, CO, USA
Abstract :
Matching input/output (I/O) driver output resistance to transmission line impedance is critical for high-speed I/O operation in source series termination environments. Tuning driver output resistance can be accomplished through the use of calibration circuitry. Under ideal conditions, calibration circuitry can properly calibrate an I/O driver. Operating in an environment with die process, voltage, and temperature variations, that same calibration circuitry may perform improperly. This brief presents an I/O driver design that is less sensitive to process, voltage, and temperature variations. The proposed driver design provides a near linear or flat, output resistance response verses output voltage. Advantages of the proposed I/O driver architecture lie in applications where the output DC operating point may have a large variation, thus, reducing the error in matching output resistance.
Keywords :
CMOS integrated circuits; driver circuits; impedance matching; integrated circuit design; DC operating point; I/O driver architecture; calibration circuitry; high speed I/O operation; input-output driver output resistance; linear CMOS I/O driver; output resistance response; output voltage variations; source series termination environments; temperature variations; transmission line impedance; tuning driver output resistance; CMOS process; Calibration; Circuit optimization; Digital control; Distributed parameter circuits; Driver circuits; FETs; Impedance matching; Temperature sensors; Voltage control; Driver output impedance matching; I/O performance; process variation; programmable I/O driver;
Journal_Title :
Very Large Scale Integration (VLSI) Systems, IEEE Transactions on
DOI :
10.1109/TVLSI.2004.836321
