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:
Jun. 27, 2006
Filed:
Jul. 14, 2004
Yao Tung Yen, Cupertino, CA (US);
Yao Tung Yen, Cupertino, CA (US);
Pericom Semiconductor Corp., San Jose, CA (US);
Abstract
A low-power memory module has an active termination circuit at each end of critical signal traces. The dynamic termination circuit has a low-value resistor that is connected to a termination voltage by a transmission gate that is turned on by a switch signal. The switch signal is activated when the memory module is selected by a chip-select signal, and when a time window is open. The time window is generated from the clock to synchronous DRAMs on the memory module. The time window can be one-quarter of the clock period by ANDing the clock and a delayed clock that is delayed by one-quarter of a cycle. A static terminating resistor in parallel with the low-value resistor provides a much smaller terminating current that is not switched on and off. Traces can be impedance-matched at junctions to branches that each has a dynamic termination circuit at the far end.