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. 01, 2007
Filed:
Aug. 27, 2004
Hoang Minh Pinai, Saratoga, CA (US);
Hoang Minh Pinai, Saratoga, CA (US);
ZiLOG, Inc., San Jose, CA (US);
Abstract
A below-ground sensor interface amplifier is powered by no negative supply voltage, but the amplifier nevertheless senses an input voltage signal below ground potential. The amplifier outputs an output voltage signal that varies proportionately to the input voltage. For an input voltage beginning below ground potential and increasing past ground potential, the amplifier outputs an output voltage that remains between ground potential and a supply voltage. The output voltage increases proportionately to the increase of the input voltage. As the input voltage increases, a gate voltage on a first transistor begins to increase starting at the input voltage at which a second transistor is forced to turn on. The amplifier senses input voltages more than one threshold voltage below ground potential without using a below-ground supply voltage. The gain of the amplifier, as well as the lower limit and the size of the amplifier's voltage operating range are programmable.