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:
Jul. 30, 1991
Filed:
Jan. 16, 1990
Frank J Cichanski, Elgin, IL (US);
Other;
Abstract
A monitoring circuit for a battery charger, with utility in other applications, includes a main input that receives an initial signal such as the terminal voltage of a battery being charged, and a two-stage comparator, each stage preferably an operational amplifier. The initial signal is applied to the inverting input of the first stage, which is a differencing amplifier that also serves as a gain block; the initial signal is also delayed a brief interval, typically more than a second, and then applied to the non-inverting input of the first stage of the comparator. The inverting input of the second stage of the comparator receives the same signal as the non-inverting input to the first stage, whereas the non-inverting input to the second stage is derived from the output of the first stage. The output of the second stage varies in amplitude and polarity to define trends in the initial signal direction and magnitude and, in a battery charger, allows accurate charging to a peak with virtually no overcharge or undercharge problems.