Specifications

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3.10. Power System and Power Consumption
EM-X270 Power Management Concepts
The EM-X270 system is designed as a handheld device, providing minimized power
consumption operation, very low power sleep mode, on-line battery replacement capability
and long battery life.
The main power supply source is a rechargeable lithium battery. A regulated DC power
source of 3.7V – 4V may also be used, but this will require software adaptation.
An on-board rechargeable coin cell battery provides back-up power in standby and off
modes.
The DA9030 PMIC manages most of the EM-X270's power system, providing regulated
voltages for the PXA270 processor, memories and peripheral devices.
Certain units of the EM-X270 are powered by discrete voltage regulators connected
directly to the main battery and controlled by PXA270 GPIO’s.
Battery charging and supervision are also managed by the DA9030.
EM-X270 Batteries
The EM-X270 system is designed to operate with a rechargeable lithium battery.
The battery pack must include an NTC thermistor for temperature measurement during
battery charging.
The EM-X270 power management software was designed to operate with the 10W/h Li-
Polymer battery available from Compulab. Custom batteries may also be integrated with
the EM-X270, but this will require software adaptation. The following battery chemistries
are supported by EM-X270:
 Single-Cell Li-Ion at 4.1V
 Li-Polymer Pack
Please see the “Battery charger control” section in the DA9030 datasheet for more details.
An on-board 14mAh rechargeable coin cell lithium battery is the back-up power supply for
RTC timekeeping. This battery is constantly being charged whenever the main battery is
present.