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:
Jan. 29, 1991
Filed:
Mar. 22, 1990
Abstract
The additional voltage drop across a guard diode against supply polarity inversion in an integrated bridge circuit for driving an external load and employing two high-side NPN power switches driven by two PNP transistors, all monolithically integrated using a junction-type isolation technique, is substantially eliminated by connecting the emitters of the two PNP drive transistors directly to the positive rail, i.e. to the anode of the guard diode. Integrated PNP transistors are per se intrinsically protected against polarity inversion and when so connected permit to reduce the overall voltage drop across the driving bridge circuit. Using a Zener diode as the guard diode and a second Zener diode connected in opposition to the first Zener between the cathode thereof and the negative supply rail an additional spike protection of the circuit's components is implemented.