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:
Jun. 05, 2007
Filed:
Dec. 29, 2004
Jean-charles Grasset, Moirans, FR;
Frédéric Bossu, San Diego, CA (US);
Jean-Charles Grasset, Moirans, FR;
Frédéric Bossu, San Diego, CA (US);
STMicroelectronics S.A., Montrouge, FR;
Abstract
Attenuation cell comprising first and second differential pairs of bipolar transistors. A gain control device applies a voltage VA−VB between the bases of both differential pairs and comprises a set of three diodes in which a current IA, a current IB and the sum IA+IB of both preceding currents flow, respectively. The two diodes seeing current IB and IA+IB generate a voltage, respectively VB and VC, and the difference between these two voltages is used to generate a value Iz used in a control loop. A desired value Vct is transformed into information Ix, then into information Iy proportional to absolute temperature T, and an error amplifier uses information Iy−Iz and generates currents IA and IB by minimizing this difference.