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6.3 Charging Concept
Charging current
Charging control signal
6.3.1.1
Charging Concept
General
The battery is charged in the unit itself. The hardware and software is designed for LiIon with 4.2V
technology.
Charging is started as soon as the phone is connected to an external charger. If the phone is not
switched on, then charging takes place in the background (the customer can see this via the "Charge"
symbol in the display). During normal use the phone is being charged (restrictions: see below).
Charging is enabled via a PMOS switch in the phone. This PMOS switch closes the circuit for the
external charger to the battery. The
charge level of the battery, whereby a disable function in the
override/interrupt the charging in the case of over voltage of the battery (only for Manganese Chemistry
Battery types e.g. NEC).
With the new slim Lumberg IO connector we lose the charger recognition via SB line. Now we measure
the charge current inside the
The charging software is able to charge the battery with an input current within the range of 350-600mA.
If the Charge-Fet is switched off, then no charging current will flow into the battery (exception is trickle
charging, see below).
For controlling the charging process it is necessary to measure the ambient (phone) temperature and
the battery voltage. The temperature sensor will be an NTC resistor with a nominal resistance of 22kΩ
at 25°C. The determination of the temperature is achieved via a voltage measurement on a voltage
divider in which one component is the NTC. The NTC for the ambient temperature will be on the PCB
(13 MHz part).
Measurement of Battery, Battery Type and Ambient Temperature
The voltage equivalent of the temperature and battery code on the voltage separator will be calculated
as the difference against a reference voltage of the EGOLD. For this, the integrated Σ∆ converter in the
EGOLD
of the RX-I base band branch will be used. Via an analogue multiplexer, either the RX-I base
band signal, the battery code voltage or the ambient temperature voltage can be switched over to the
input of the converter. The 1-Bit data stream of the converter will be subjected to a data reduction via
the DSP circuit so that the measured voltage (for battery and ambient temperature) will be available at
the end as a 10-bit data word.
V 1.10
A52/A55/C55 IFX
EGOLD+
takes over the control of this switch depending on the
POWER SUPPLY ASIC
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POWER SUPPLY ASIC
with a current monitor.
hardware can
ICM MP CCQ GRM
08/03
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