Power supply system for memory unit of camera
US4662736A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 24, 1985 |
| Grant date | May 5, 1987 |
| Priority date | — |
| Expiry date | Dec 24, 2005 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03B7/26
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An electronic appliance having a microcomputer, peripheral devices controlled by the microcomputer, a main battery acting as power source, and a backup battery for backing up the main battery. Checking is made of whether the main battery is loaded in the appliance or not and whether the output voltage of the main battery is above a predetermined voltage or not. When the main battery is not loaded or when its output voltage is below the predetermined voltage, the backup battery is made available for preserving information in the memory inside or outside the microcomputer in good order, with operations of the peripheral devices being restricted at such times. Further, the disclosed electronic appliance includes means to prevent malfunctioning of the microcomputer and the peripheral devices when a new main battery has been loaded in the appliance as replacement for an exhausted main battery.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.