US 7,489,725 B2
Decision feedback equalizer and precoder ramping circuit
Steven T. Jaffe, Irvine, Calif. (US); Robindra Joshi, Redondo Beach, Calif. (US); David Jones, Louisville, Colo. (US); and Thuji Simon Lin, Irvine, Calif. (US)
Assigned to Broadcom Corporation, Irvine, Calif. (US)
Filed on May 19, 2004, as Appl. No. 10/848,907.
Application 09/619125 is a division of application No. 09/550757, filed on Apr. 17, 2000, abandoned.
Application 10/848907 is a continuation of application No. 09/619125, filed on Jul. 18, 2000, abandoned.
Claims priority of provisional application 60/148978, filed on Aug. 13, 1999.
Claims priority of provisional application 60/148801, filed on Aug. 13, 1999.
Prior Publication US 2004/0252755 A1, Dec. 16, 2004
Int. Cl. H03K 5/159 (2006.01)
U.S. Cl. 375—233  [375/348] 20 Claims
OG exemplary drawing
 
1. A receiver comprising:
a feedforward filter coupled to process signals received by the receiver, the feedforward filter comprising,
a plurality of feedforward filter taps for mitigating pre-cursor intersymbol interference, including a feedforward filter reference tap, and
a coefficient for each feedforward filter tap, wherein the feedforward filter reference tap is located proximate a center position of the plurality of feedforward filter taps;
a feedback filter coupled to receive signals representative of an output of the feedforward filter, the feedback filter having a plurality of feedback filter taps each having a coefficient, and
a ramping circuit assembly comprising,
an input port configured to receive at least one feedback filter tap coefficient from the feedback filter;
a coefficient ramping circuit configured to provide a ramped output for at least one feedback filter tap coefficient, the ramped output being varied over time from a first value to a second value, the second value being dependent upon the at least one feedback filter tap coefficient, and
an output port configured to communicate information representative of the ramped output to a precoder.