The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 04, 2008
Filed:
Feb. 28, 2006
Manfred Mauthe, Grosshelfendorf, DE;
Henrik Icking, München, DE;
Manfred Mauthe, Grosshelfendorf, DE;
Henrik Icking, München, DE;
Infineon Technologies, Munich, DE;
Abstract
In order to generate a control signal for adjusting a driver stage with an adjustable output impedance, an impedance signal is generated for a measure of the output impedance of the driver stage. The difference between the impedance signal and a reference signal is calculated, and passed to a sigma-delta modulator to generate a digital bitstream signal. The control signal is then generated depending on the bitstream signal, where the frequencies of the two signal states in the bitstream signal are evaluated by means of digital counters. Depending on the difference of the determined frequencies of the two signal states, a counter is increased or reduced, and the control signal is generated depending on the count of the counter. The impedance signal may be generated by a replica circuit of a pull-up region or a pull-down region of the driver stage to be adjusted.