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. 03, 2012
Filed:
Apr. 10, 2008
Shunzou Ohshima, Kosai, JP;
Shunzou Ohshima, Kosai, JP;
Yazaki Corporation, Tokyo, JP;
Abstract
To provide an overcurrent protection apparatus which can surely protect a load circuit from an overcurrent with a simple configuration. Supposing that the temperature increasing amount of a semiconductor element caused when the semiconductor element is turned on is ΔTch, the on-resistance value of the semiconductor element (T) is Ron, the thermal resistance value of the semiconductor element (T) is Rth_f, the temperature increasing amount of a connecting wiring is ΔTw when a current flows into the connecting wiring (WL), the resistance value per unit length of the connecting wiring is Rw, and the thermal resistance value per unit length of the connecting wiring is Rth_w, ΔTch is obtained based on an expression of ΔTW/ΔTch=Rth_w/Rth_f*Rw/Ron with respect to the temperature increasing amount ΔTw not exceeding a difference between the upper limit of the permissible temperature of the connecting wiring (WL) and the upper limit of an operational peripheral temperature, then a voltage Vds is obtained based on an expression of ΔTch=Rth_f*Vds/Ron with respect to the ΔTch thus obtained, and the voltage Vds thus obtained is set as a determination voltage.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile