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:
Jan. 02, 2007
Filed:
May. 24, 2002
Gianni Puccio, Cagnes-sur-Mer, FR;
Biagio Bisanti, Antibes, FR;
Stefano Cipriani, Golfe Jan, FR;
Texas Instruments Incorporated, Dallas, TX (US);
Abstract
A phase lock loop circuithas a phase frequency detector, a charge pump, an active filterand a voltage-controlled oscillator. The phase detector generates UP and DN signals indicative of the relative frequency of F, a reference signal, and F, a signal controlled by the voltage-controlled oscillator. A charge pump using logic gates (bufferand inverter) to produce a voltage drop over resistorsandto generate a voltage at a node coupled to the input of transmission gateaccording to the values of the UP and DN signals. When the transmission gateis closed (low impedance) the charge pump may sink or source current to the inverting input of the operational amplifierof the active filter. When the transmission gate is open (high impedance state) the inverting input is electrically isolated from the node.