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:
Apr. 15, 2008
Filed:
Mar. 10, 2006
Takatsugu Kamata, Yokohama, JP;
Takatsugu Kamata, Yokohama, JP;
RfStream Corporation, Osaka, JP;
Abstract
A current source generates a constant current using metal oxide semiconductor (MOS) transistors. A biasing circuit generates a biasing current based on the transconductance of the MOS transistors. A load circuit, comprising a resistor coupled in parallel with a MOS transistor, generates a constant load current from the biasing current. The load current comprises the sum of a resistor current, which flows through the resistor, and a MOS current that flows through the transistor. The load current is constant because variations of the resistor current offset variations of the MOS current across temperature or process variations. A current mirror circuit generates an output current for the current source equal to a sum of the resistor current and the MOS current, the output current being approximately constant in value across temperature or process variations.