For temperature detection, a NTC resistor (22kΩ at 25°) is assembled in the
battery pack. Via the pin 2 of the battery connector connected to the
is carrying out the measurement.
The voltage is measured from the GAIM-part of the EGOLD+ (see description
In chapter 7)
If the phone has not been used for a longish time (longer than approx. 1 month), the
battery could be totally self-discharged. (battery voltage less then 3,2V), so that
it is not possible to charge the battery via the normal charging circuit. In this case
only trickle charge is possible.
Battery voltage below 2,8 Volt charging current 20mA.
Battery voltage below 3,2 Volt charging current 50mA.
Battery voltage over 3,2 Volt "Normal charging".
Power supply for the ASIC
The switch into normal charging mode, is done automatically if the required voltage
Trickle Charging Power Supply
"Normal/Trickle" charging activation
a charger voltage >15V can destroy resistors or capacitors in the charging path
a charger voltage >20V can destroy the MOS-FET switch transistor in the
C45, M50 AND MT50
controls the charging circuit himself.
in this mode is the external charger.
Page 27 of 46
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