A digital calibration algorithm for implementing accurate on-chip resistors



A digital calibration algorithm that provides a systematic method for implementing accurate integrated resistors without compromising linearity or noise performance is described. The technique uses a single external resistor as a reference to implement multiple, different valued integrated resistors without requiring any accurate reference voltage. The algorithm provides a method to calibrate several on-chip resistors without replicating the calibration circuit, and it can achieve an arbitrary accuracy limited only by the external resistor’s accuracy and mismatch errors. Terminations for two high speed wire line transceivers are implemented using the algorithm and simulations and measurements results show adequate performance across process, temperature, and supply voltage.


Calibration Circuit tuning Resistive circuits Adaptive codes CMOS integrated circuits Transmission line Digital communication 


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© Springer Science + Business Media, LLC 2006

Authors and Affiliations

  1. 1.Texas Instruments Inc.DallasUSA
  2. 2.Analog VLSI Laboratory, Department of Electrical EngineeringThe Ohio State UniversityColumbusUSA

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