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:
Apr. 27, 2010
Filed:
Sep. 25, 2008
Chik Wai David NG, Kowloon, HK;
Kwok Kuen David Kwong, Davis, CA (US);
Chik Wai David Ng, Kowloon, HK;
Kwok Kuen David Kwong, Davis, CA (US);
Abstract
A bandgap reference voltage generator has a first stage that generates a first current that is complementary-to-absolute-temperature (Ictat) and a second stage that generates a current that is proportional-to-absolute-temperature (Iptat). The Ictat and Iptat currents are both forced through a summing resistor to generate a voltage that is relatively independent of temperature, since the Ictat and Iptat currents cancel out each other's temperature dependencies. A PMOS output transistor drives current to an output load to maintain the load at the reference voltage. An op amp drives the gate of the PMOS output transistor and has inputs connected to emitters of PNP transistors in the second stage. A series of resistors generate the reference voltage between the PMOS output transistor and ground and drives bases of the PNP transistors and includes the summing resistor. Parasitic PNP transistors in an all-CMOS process are used. The generator operates with a 1-volt power supply.