Portable electronic device
First Claim
1. A portable electronic device comprising a power source terminal for connecting to an external power source, an internal power source which is lower than the external power source in voltage, first circuit means to execute first data processing, and second circuit means to execute second data processing which has lower speed than the first data processing, the electronic device being characterized in that the device is so constructed that the external power source supplies power to the device through a power source terminal when the first circuit means is in an active mode, and the internal power source supplies power to the device when the second circuit means is in the active mode.
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Accused Products
Abstract
A portable electronic device embodying the present invention comprises a USB connector, an internal power source, a USB controller to execute data communication processing for data communication with a personal computer connected to the USB connector, a main CPU to execute device operation processing for usual operation of the device. When USB controller executes data communication processing, the device is supplied with power at high voltage from the personal computer through the USB connector. When the main CPU executes device operation processing, the device is supplied with power at low voltage from the internal power source.
Accordingly, this makes not only high speed data communication available, but also life of the internal power source prolonged.
125 Citations
5 Claims
- 1. A portable electronic device comprising a power source terminal for connecting to an external power source, an internal power source which is lower than the external power source in voltage, first circuit means to execute first data processing, and second circuit means to execute second data processing which has lower speed than the first data processing, the electronic device being characterized in that the device is so constructed that the external power source supplies power to the device through a power source terminal when the first circuit means is in an active mode, and the internal power source supplies power to the device when the second circuit means is in the active mode.
Specification