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:
Aug. 27, 1996
Filed:
Dec. 01, 1994
Frank Murden, Greensboro, NC (US);
Analog Devices, Inc., Norwood, MA (US);
Abstract
A differential amplifier operating as a magnitude amplifier may be used in a serial-type A/D converter. The differential amplifier uses complementary differential emitter pairs for folding and aligning a differential input signal. The differential input signal has a first signal and a second signal each of which is fed to one of two input circuits. One input circuit includes a bipolar npn transistor and a current sink and the other includes a bipolar pnp transistor and a current source. The outputs of the input npn transistors feed a differential pair of output pnp transistors. The emitters of the output pnp transistors are coupled, with the signal on the emitters following the lower of the differential input signals. The outputs of the input pnp transistors feed a differential pair of output npn transistors. The emitters of the output npn transistors also are coupled, with the signal on the emitters following the inputs in a predetermined manner. The results are folded signals at the outputs of the output transistors that are aligned by offset circuits.