Private Communication Systems
Mobile Phones
Furthermore the ASIC generates the supply voltage for the SIM-Card and the
RESET signal for the logic devices.
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
destroyed!
5.4 Overvoltage Conditions
a) Battery Voltage: 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.
b) Charging Current: 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.
➣ Be careful with foreign accessories or chargers!
➣ Make sure that the charging current is limited to a value below 1A!
Service Manual C1x V 1.0 PN MP ST
R. Fleuren
Sm_C1x_lvl2_v10_w97.doc Page 16 of 23 09/98
