MC75i Hardware Interface Description
3.5 Charging Control
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MC75i_HD_v01.100a
Page 41 of 122
2009-08-13
Confidential / Released
3.5
Charging Control
MC75i integrates a charging management for rechargeable Lithium Ion and Lithium Polymer
batteries. You can skip this chapter if charging is not your concern, or if you are not using the
implemented charging algorithm.
The following sections contain an overview of charging and battery specifications. Please refer
to
for greater detail, especially regarding requirements for batteries and chargers, appropri-
ate charging circuits, recommended batteries and an analysis of operational issues typical of
battery powered GSM/GPRS applications.
3.5.1
Hardware Requirements
MC75i has no on-board charging circuit. To benefit from the implemented charging management
you are required to install a charging circuit within your application according to the
3.5.2
Software Requirements
Use the command AT^SBC, parameter <current>, to enter the current consumption of the host
application. This information enables the MC75i module to correctly determine the end of
charging and terminate charging automatically when the battery is fully charged. If the <cur-
rent> value is inaccurate and the application draws a current higher than the final charge cur-
rent, either charging will not be terminated or the battery fails to reach its maximum voltage.
Therefore, the termination condition is defined as: current consumption dependent on operat-
ing mode of the ME plus current consumption of the external application. If used the current
flowing over the VEXT line of the application interface must be added, too.
The parameter <current> is volatile, meaning that the factory default (0mA) is restored each
time the module is powered down or reset. Therefore, for better control of charging, it is recom-
mended to enter the value every time the module is started.
for details on AT^SBC.
