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:
Dec. 08, 1998
Filed:
Oct. 29, 1996
Nicholas Mihailovits, Sale, GB;
Trevor P Beatson, Manchester, GB;
Abstract
A filter circuit comprises three stages 260, 270, 280, each having a differential input and a differential output. The output of stage 260 serves as the input of stage 270 and the output of stage 270 serves as the input of stage 280 respectively. Stage 260 comprises two transistor pairs 201, 202 and 203, 204. An input signal is applied to the base electrodes of transistors 201, 204 which causes a current change in their opposite transistor 202, 203. Transistors 202, 203 have their respective base and collector electrodes connected together. The collector electrodes of transistors 202, 203 constitute the output of stage 260. Stages 270 and 280 have essentially the same structure as stage 260. The arrangement offers high frequency capabilities from a low supply voltage. In another embodiment, a cut-off frequency is varied under control of controllable current sources.