Low voltage power down logic control circuit
Patent 4831595 Issued on May 16, 1989. Estimated Expiration Date: 
May 6, 2007. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
May 6, 2007. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent ReferencesMemory protection system Power down circuit for data protection in a microprocessor-based system Electronic apparatus with memory backup system Non-volatile data stores Patent #: 4611302 InventorApplicationNo. 07/047085 filed on 05/06/1987US Classes:365/229Standby powerExaminersPrimary: Moffitt, James W.Attorney, Agent or FirmInternational ClassG11C 5/14 (20060101)AbstractA power down logic control circuit employing a diode and a capacitor to develop a voltage from a main power supply which normally holds a transistor in an "off" state. Upon disconnection of the main supply, the transistor switches "on" and activates a second transistor. Upon activation, the second transistor produces an inhibit signal to tri-state memory control circuitry and thereby preserve the memory data during transition to standby memory power provided by a lithium battery.Field of SearchStandby power | |
