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. 28, 2005
Filed:
Apr. 05, 2001
Anthonius Bakker, Delft, NL;
Johan H. Huijsing, Schipluiden, NL;
Anthonius Bakker, Delft, NL;
Johan H. Huijsing, Schipluiden, NL;
Koninklijke Philips Electronics N.V., Eindhoven, NL;
Abstract
An amplifier (AMP) is provided with a pair of choppers (CHP,CHP) in order to reduce the DC-offset and the noise produced by the amplifier (AMP). To obtain an optimal noise reduction the pair of choppers (CHP,CHP) operate on a high frequency. As a result the DC-offset cancellation is not optimal because a so-called charge injection of the switches in the pair of choppers (CHP,CHP) produces a DC-offset. To overcome this problem the amplifier (AMP) is further provided with further offset cancellation means which are for example formed by a further pair of choppers (CHP,CHP). This further pair of choppers (CHP,CHP) operates on a relatively low frequency. The combination of the pair of choppers (CHP,CHP) and the further pair of choppers (CHP,CHP) guarantees an optimal DC-offset cancellation as well as an optimal noise cancellation.