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. 25, 2010
Filed:
Jun. 07, 2006
David R. Staab, Los Gatos, CA (US);
David R. Staab, Los Gatos, CA (US);
ZiLOG, Inc., San Jose, CA (US);
Abstract
A microcontroller receives a supply voltage (VCC) from one or more batteries. Rather than automatically resetting the microcontroller if VCC drops below a VBO voltage, a latent VBO reset circuit does not reset the processor if VCC drops below a second voltage (VBO) as long as VCC does not fall so low that a power on reset (POR) circuit of the latent VBO reset circuit is tripped. The processor continues to operate as long as it can below VBO, thereby maximizing battery usage. When VCC rises to a third voltage (for example, due to battery replacement), then the latent VBO reset circuit automatically resets the processor to remove potential ill-effects of having operated below VBO. User data stored in volatile memory is not lost during battery replacement. A special VBO bit in a processor-readable status register indicates that the microcontroller operated below VBO.