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Battery charging controller – ThingMagic Mercury xPRESS Platform v1.7 User Manual

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A D I V I S I O N O F T R I M B L E

108

Hardware Reference Guide

available externally through the Comm Bus interfaces. The Reset and Shutdown lines are
controlled by the processor.

No antenna is provided with the xPRESS platform, but an MMCX-to-Reverse-TNC
adapter cable is provided so the platform can be used with off-the shelf antennas.

Battery Charging Controller

The LTC 4098 Battery Charging Controller, and the switches it controls, form the heart of
the power management system. Functionality controlled by this IC include:



Over-voltage protection for the power from the AC Adapter port



Sourcing power from the AC adapter port when both it and USB power are present



Switching between the battery powering the system and the AC source or USB port

both powering the system and charging the battery based on battery charge level
and power demand from the system.



Charging the battery with the optimum level of current while monitoring the battery

temperature (if the battery is equipped with an “NTC” sensor).

More information about power management is provided in the

Power Source Precedence

section of this chapter.