5.7 Battery Charging Input (CHG_IN)

Pin

 

Name

 

Direction

 

Function

 

 

 

 

 

 

 

11

 

CHG_IN

 

Input

 

Battery charger power

For battery powered applications, the GR64 provides a charge input (CHG_IN) pin to aid and support battery charging. A typical application would power the wireless modem directly from a battery source connected to VCC (pins 1, 3, 5, 7, 9) then provide a dc power source to the CHG_IN connection (pin 11). The GR64 can control an internal switching FET which creates a charging pathway to the battery. While power is provided at CHG_IN, the battery charge can be maintained. If the power should fail or be removed at CHG_IN, the application will be supported by the battery alone. When CHG_IN voltage returns, the battery charging and maintenance will commence once more.

The GR64 module supports only one mode of charging, microprocessor supervised pulsed-charging. Also, the module only supports one battery cell type as standard. Users may, if they wish, develop charging algorithms and control through the Sony Ericsson M2mpower Embedded Applications. Users wishing to attempt charging of battery types not supported by the standard type, indicated in this document, do so at their own risk.

Battery charging algorithms are unique to different battery types. Sony Ericsson Mobile Communications will not accept any responsibility or liability for damage, product failures, even death or injury occurring as

DANGER

a result of incompatible battery and charging algorithms being applied.

 

Safety considerations must be taken into account when using the battery charge function of the GR64; for example, monitoring the temperature of the battery. If the temperature of the battery exceeds its specification limits, battery charging must be stopped immediately. If the battery temperature continues to rise the application should be suspended or the battery disconnected. Battery temperature can be monitored with a suitable detection circuit, using the GR64 ADC inputs.

When charging Lithium batteries, the battery pack must have an internal protection circuit in accordance with the manufacturer's instructions.

CAUTION

During microprocessor supervised mode, the GR64 takes a current-limited voltage source at the CHG_IN pin to implement constant-current charging of a single Li-Ion cell connected to the VCC pins.

LZT 123 1834

41