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:
Mar. 30, 1999
Filed:
Sep. 19, 1997
Robert Bosch GmbH, Stuttgart, DE;
Abstract
A circuit arrangement for converting a DC voltage into another DC voltage, with simultaneous regulation of the emittable voltage (U.sub.A) at a predetermined value. The circuit arrangement includes a combination of an upward and a downward transformer having at least one switching transistor (3) connected in series with a common memory coil (1) to a circuit output terminal, and a smoothing capacitor (5) connected in parallel to the output load (6), i.e., across the output terminals. The coil (1) is connected for a specific time to the supply voltage source (U.sub.Bat) by a time function circuit (9, 10). The coil (1) is connected directly to the positive pole (+) of the supply-voltage source (U.sub.Bat), and a current limiter circuit is provided in the long or forward branch of the circuit arrangement in front of the output of the circuit arrangement, with the current limiter circuit comprising a resistor (4) and a transistor (15) and influencing the switching transistor (3) disposed in the long branch. In addition to a first voltage limiting circuit formed of a series connection of a resistor and a Zener diode (16, 17), a further voltage limiter circuit (18, 19) is provided in parallel with the first voltage limiting circuit as short-circuit protection, with the further limiter likewise comprising the series connection of a resistor (18) and a Zener diode (19) which, however, has a different breakdown voltage than the first Zener diode (17).