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:
Jan. 01, 2002
Filed:
Jun. 13, 2000
Other;
Abstract
When a level of an asynchronous internal clock enabling signal asynchronous with an external clock signal is risen just after or just before a level change of the external clock signal, a for-synchronization-circuit enabling signal synchronized with the external clock signal is produced in a control signal producing circuit on condition that a level of the for-synchronization-circuit enabling signal is risen at a time which is later than the level change of the external clock signal by two clocks of the external clock signal. Therefore, a reset time-period from the level change of the external clock signal to the level change of the for-synchronization-circuit enabling signal, is obtained. A synchronization circuit is reset in the reset time-period according to the external clock signal and the asynchronous internal clock enabling signal, and, a test signal is produced in the synchronization circuit from the for-synchronization-circuit enabling signal after the reset time-period passes. Therefore, because the for-synchronization-circuit enabling signal is not received from the outsides but is produced, a circuit area of a semiconductor integrated circuit can be efficiently used.