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. 07, 2014
Filed:
Aug. 07, 2012
Ming Chen, Shanghai, CN;
Shu Dong Cheng, Nanjing, CN;
Ming Chen, Shanghai, CN;
Shu Dong Cheng, Nanjing, CN;
Agere Systems LLC, Allentown, PA (US);
Abstract
Described embodiments include a level shifter that provides a voltage level shift to applied signals, the amount of voltage shift being accurately controlled and independent of PVT. The level shifter has first transistor configured as a voltage follower with the gate coupled to an input terminal of the shifter and the source coupled to a node, a diode-connected transistor coupled between the node and an output terminal of the circuit, a first controlled current source coupled to the node, and a second controlled current source coupled to the output terminal. A controller receives a bandgap-stabilized voltage, squares the stabilized voltage to produce a control signal that controls the first and second controlled current sources. The voltage shift is proportional to a digitally-controlled scale factor (K) times the stabilized voltage. The ratio of the current from the first current source to the second current source is (K+1)/K.