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Accessories
Phone On/Off Status
The VDD input indicates whether the phone is Off or On and will inform the CPU if
the phone has been removed during charging.
Discharger
To prolong the battery life the rear slot is equipped with a reconditioning feature.
By pressing the discharge switch (same as the rear LED indicator), the CPU
becomes notified that it will have to carry out a discharge operation on the battery in
the rear slot.
The CPU then activates the discharge operation by draining the battery at a suitable
resistive load.
LED Indicators
The LEDs are used for indication of the various charging phases.
Front LEDs
The two front LEDs (green and red) can be On and Off in any combination except
both On.
Rear LEDs
The two rear LEDs (green and red) can be On and Off in any combination.
Temperature Guard
A temperature related voltage is generated due to an onboard NTC resistor and fed
to an input of the CPU for detection and measures to prevent overheating. The
threshold is set to +55°C onboard corresponding to an ambient temperature of
+35°C.
Power Distribution for Phone Operation
The power to the front slot for phone operation is entirely controlled by the phone.
The various current values needed in different situations, like stand-by or transmis-
sion, are programmed and stored in the telephone.
The MC7000 is able to deliver 500 - 700 mA to the phone depending on the power
source is being connected.
Battery Charging
The charging of both batteries is turned on and off by a switch circuitry which is
controlled by the Central Processing Unit. Charging is only possible for one slot at a
time where the front slot has got highest priority, i.e. charging of the spare battery
will not begin until the phone battery is fully charged or removed.
The batteries being used are four 1.2V cell NiMH (Nickel-Metal-Hydride) or NiCd
(Nickel-Cadmium) chargeable batteries, without internal thermistor.
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