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. 24, 2001
Filed:
Dec. 16, 1999
Wolfgang Edeler, Vreden, DE;
Nokia Mobile Phones Ltd., Espoo, FI;
Abstract
The invention concerns an amplifier circuit for an IC whereby continuous symmetrical signal routing can be provided from the inputs to the outputs, without branches and crossovers and at low cost. The IC can be used as amplifier, buffer, line driver and line receiver with a minimum of external wiring. Two operational amplifiers (OA,) and (OA,) are each connected as non-inverting amplifiers and include integrated feedback impedances (RF,, RF,), a joint resistor (R,) for adjusting the differential amplification, and a subtraction stage. According to the invention two complementary, parallel-connected differential amplifiers (DIF,and DIF,) form the subtraction stage, each of which has its own pair of signal outputs (O,/O,or O,/O,) for one differential signal in each case. Each of the signal outputs (O,/O,or O,/O,) leads to its own driver (DV,, DV,, DV,and DV,), which are interconnected so as to create a push-pull output stage in a bridge circuit.