Overvoltage Conditions - Siemens C25 Service Manual

Furthermore the ASIC generates the supply voltage for the SIM card and the RESET
signal for the logic devices.
Attention:
The telephone supplies the SIM card with 3Volts, meaning 5V-SIMs are not
supported. In case a user inserts such a 5Volt card, the telephone will not recognise
it and prompt to insert a SIM card the same way as it would in case there is no SIM
inserted.
Telephone is not defective. The way to solve this is to get the SIM exchanged by the
operator or service provider to a 3V type.
The ASIC also checks the presence of the watchdog signal from the µP and provides
the switching on functionality (ON_OFF button or Ignition signal).
During testing ist is advisable to use a battery dummy, connected to a power supply
delivering +4V, max 3A.
Make sure that you connect the battery dummy with the right polarity, the red plug to
+4V and the blue plug to ground.
If you use a voltage higher than +7V, or with wrong polarity, the phone can be
damaged!
5.4

Overvoltage Conditions

a) Battery Voltage:
b) Charging Current:
ã
Be careful with foreign accessories or chargers!
ã
Make sure that the charging current is limited to a value below 1A!
Service Manual C25 / C2588
Sm_C25_lvl2_v10_w97
If the supply voltage rises above 6.2 Volts, the phone will
switch off and it cannot be switched on again before the
voltage is lower than 6.2 Volts.
If the supply voltage rises above 7 Volts the phone can be
destroyed.
The charging current must not rise above 1 A or the
phone (fuse) will be inoperable, meaning that charging the
battery will not be possible anymore.
V 1.0
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