Hi,
	I need to develop an application that will run on 4 AA Ni-Me
batteries. It will have a PIC18F6xJ50 (3.3V) a RTC, external EEPROM and a
graphic lcd, capable of working at 3.3V and at 5V.

	The device is required to be able to charge the batteries from the
USB port.

	Assuming a battery voltage from 1.6V to 0.9V (the user would use
alkaline batteries) the voltage range of the device will be from 3.6V to
6.4V. 

	I can't find some elegant solution to solve both the supply to the
electronics and charging the batteries. Would it be correct to use some step
down switching to get 3.3V and a step-up to boot from the 5V on the USB to
the 6.4V needed to charge the batteries.

	Any comments will be really appreciated.

Regards,

Mauricio



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