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:
Oct. 30, 2012
Filed:
Oct. 30, 2009
Date Jan Willem Noorlag, Fremont, CA (US);
Michael Frank, Sunnyvale, CA (US);
Date Jan Willem Noorlag, Fremont, CA (US);
Michael Frank, Sunnyvale, CA (US);
Apple Inc., Cupertino, CA (US);
Abstract
An aging detection circuit is disclosed. An aging detection circuit may include at least an inverter and a half-latch. During a power-up sequence, if an input voltage of the first inverter changes sufficiently to cause the output of the inverter to change states, the output of the half-latch may be set to a state indicating aging of the circuit. This indication may be used in determining whether or not a supply voltage should be changed to compensate for the aging. A first transistor of the inverter may be arranged such that it remains active subsequent to power-up of the circuit. When active, the first transistor may be subject to degradation mechanisms associated with aging and which change its threshold voltage. The threshold voltage may change such that on a successive power-ups of the circuit, the first transistor is at least momentarily deactivated, leading to the setting of the state indicating aging by the half-latch circuit.