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:
Dec. 04, 2001
Filed:
Jul. 23, 1998
Kiyoshi Nishimura, Kyoto, JP;
Rohm Co., Ltd., Kyoto, JP;
Abstract
It is an object of the present invention to provide a simulation apparatus capable of easily evaluating dynamic characteristics of a circuit including a ferroelectric device quantitatively. Means,and,calculate dynamic capacitance of a without-polarization reversal term, Cp, and a with-polarization reversal term, Cr, respectively, by differentiating the without-polarization reversal term fQp and the with-polarization reversal term fQr, respectively, representing simple saturation functions with the voltages applied to the ferroelectric part. Means,calculates dynamic capacitance Cd of the ferroelectric part by composing both the dynamic capacitance Cp and the dynamic capacitance Cr. Means,determines dynamic time constants &tgr; of the circuit including the ferroelectric part in accordance with the dynamic capacitance Cd. Means,determines both transient charge response q(t) and transient current response i(t) and the like in accordance with the time constants &tgr;. The transient responses can be simulated by using the without-polarization reversal term fQp and the with-polarization reversal term fQr both representing simple saturation functions.