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. 06, 2009
Filed:
May. 27, 2004
Wenhai NI, High Point, NC (US);
Kelvin Kai Tuan Yan, Oak Ridge, NC (US);
Mark Alexander John Moffat, Santa Cruz, CA (US);
Wenhai Ni, High Point, NC (US);
Kelvin Kai Tuan Yan, Oak Ridge, NC (US);
Mark Alexander John Moffat, Santa Cruz, CA (US);
RF Micro Devices, Inc., Greensboro, NC (US);
Abstract
A variable load circuit for adjusting a phase of a differential signal including a first transistor having a first terminal adapted to receive a first component of the differential signal, a second transistor having a first terminal adapted to receive a second component of the differential signal and a second terminal coupled to a second terminal of the first transistor, and a variable current source coupled to a third terminal of both the first and second transistors. The variable current source generates a bias current based on a control signal. For each of the first and second transistors, a first capacitance is created between the first and second terminals, and a second capacitance is created between the first and third terminals. The first and second capacitances are each a function of the bias current and thus the control signal and operate to adjust the phase of the differential signal.