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:
Mar. 25, 2008
Filed:
Oct. 13, 2006
Yasuhiro Takai, Tokyo, JP;
Shotaro Kobayashi, Tokyo, JP;
Yasuhiro Takai, Tokyo, JP;
Shotaro Kobayashi, Tokyo, JP;
Elpida Memory, Inc., Tokyo, JP;
Abstract
A delay circuit includes a first delay line circuit having a plurality of stages of delay units, a second delay line circuit having a plurality of stages of delay units, a plurality of transfer circuits provided in association with respective stages of the delay units of the first delay line circuit, the transfer circuits controlling the transfer of the outputs of the delay units of the first delay line circuit to associated stages of the delay units of the second delay line circuit. The delay units of respective stages of the first delay line circuit inverting input signals. Each stage delay unit of the second delay line circuit includes a logic circuit receiving an output signal of the transfer circuit associated with the delay unit in question and an output signal of a preceding stage to send an output signal to a following stage. The duty ratio is rendered variable by independently selecting the rising edge of the input signal and a propagation path of the falling edge.