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:
Oct. 19, 1999
Filed:
Jun. 27, 1996
Masayuki Ehiro, Nara, JP;
Sharp Kabushiki Kaisha, Osaka, JP;
Abstract
To measure the threshold characteristics of an integrated circuit processing a Schmitt circuit at the input side, a clock signal generated from a signal generator is fed to the integrated circuit, and a change of a power source current supplied from a power source circuit to the integrated circuit is detected by a change detector. A control circuit sets the amplitude of a clock signal generated by a driver circuit through digital-to-analog converting circuits. Initially, the voltages of the signal at the high level side and low level side are both set at 0.00 V, and when the voltage of the signal at the high level side, increasing by 0.01 V at a time, reaches the threshold of the Schmitt circuit, a large power source current flows, and a voltage change between the ends of a resistor is detected. As a part of a function test of a test apparatus, the threshold characteristic of the integrated circuit is measured.