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:
Aug. 28, 2012
Filed:
Dec. 21, 2009
Applicants:
Benedict C. K. Choy, Cupertino, CA (US);
Jimes Lei, Milpitas, CA (US);
Inventors:
Benedict C. K. Choy, Cupertino, CA (US);
Jimes Lei, Milpitas, CA (US);
Assignee:
Supertex, Inc., Sunnyvale, CA (US);
Attorneys:
Primary Examiner:
Int. Cl.
CPC ...
H02H 3/20 (2006.01); H02H 9/04 (2006.01);
U.S. Cl.
CPC ...
Abstract
A two terminal transmit receive device passes small analog signals with a constant low resistance value to the input of a low noise, low voltage receiver amplifier and can protect the input against the high voltage transmit signals in ultrasound applications without the aid of any power supplies. The device uses depletion-mode transistors that are normally on to pass small analog signal and a voltage detection circuit that quickly turns off the depletion-mode transistors when the presence of high voltage is detected.