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:
Aug. 04, 1987
Filed:
Mar. 28, 1986
Joseph A Plagge, Drachten, NL;
U.S. Philips Corporation, New York, NY (US);
Abstract
A self-oscillating power supply circuit for charging a battery in which energy is stored in a transformer (Tr) during the so-called forward intervals. This energy is applied as a charge current to the battery (6) during the flyback intervals. To prevent overcharge of the battery, the circuit includes a battery voltage protection circuit (10) receiving its power supply from the battery. A fraction of the battery voltage is applied to this circuit by means of a voltage divider (R.sub.3, R.sub.4) connected across the battery by means of a switch (S.sub.1) during the flyback intervals. To prevent the voltage drop across the internal resistance of the battery from influencing the measurement of the battery voltage, the battery voltage is measured after the end of a flyback interval and before the commencment of the next forward interval. This is achieved by short-circuiting the inputs (11, 12) of the protection circuit (10) by means of two diodes (D.sub.1, D.sub.2) during the flyback intervals.