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. 04, 2017
Filed:
Jul. 17, 2015
Analog Devices, Inc., Norwood, MA (US);
Alexandru A. Ciubotaru, Somerset, NJ (US);
Analog Devices, Inc., Norwood, MA (US);
Abstract
A programmable charge pump, such as for use in CMOS phase-locked loop circuits, is provided. In an example, the charge pump includes a reference stage that provides DC signals to an output stage of the charge pump. The output stage includes output switches for generating output pulses in accordance with external control signals. In an example, loop performance can be improved when an output stage of the charge pump provides a relatively large output impedance. The output switches can be isolated when the charge pump is in an OFF state. For example, respective isolation switches can be used to substantially concurrently switch source and drain terminals for each of the output switches in the charge pump. In an example, a reference stage of the charge pump can provide a buffer for reducing charge-sharing between the output switches and an output node of the output stage.