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:
May. 08, 2007
Filed:
Jan. 31, 2005
Cynthia A. Torres, Austin, TX (US);
Lloyd P. Matthews, Buda, TX (US);
Cynthia A. Torres, Austin, TX (US);
Lloyd P. Matthews, Buda, TX (US);
Freescale Semiconductor, Inc., Austin, TX (US);
Abstract
A circuit implements a method to adjust input/output (I/O) characteristics of an I/O pad circuit () depending upon which value of an I/O supply voltage is used within a range of supply voltages. An I/O supply voltage being supplied to the pad circuit is detected by detecting () its value relative to a known reference (). Portions of the I/O pad circuit are selectively enabled in response to the detected I/O supply voltage. By selecting the ratio of P-channel and N-channel transistors, physical characteristics of the circuit are controlled. Examples of the controlled physical characteristics include slew rate, signal rise and fall times, and duty cycle control which is controlled by forcing all rising and falling edges to have a midpoint at the same point in time. Therefore a same I/O pad circuit may be optimally used in numerous applications regardless of the supply voltage value.