Siemens A55 Repair Documentation page 36

Hide thumbs Also See for A55:
Table of Contents

Advertisement

Normal Charging
For battery voltages above 3.2 Volt and normal ambient temperature between 5 and 40°C the battery
can be charged with a charge current up to 1C*. This charging mode is SW controlled and starts if an
accessory (charger) is detected with a supply voltage above 6.4 Volt by the
The level of charge current is limited/controlled by the accessory or charger.
INFO:
* C-rate
The charge and discharge current of a battery is measured in C-rate. Most portable batteries, are
discharge with 1C. A discharge of 1C draws a current equal to the battery capacity. For example, a
battery value of 1000mAh provides 1000mA for one hour if discharged at 1C. The same battery
discharged at 0.5C provides 500mAfor two hours. At 2C, the same battery delivers 2000mA for 30
minutes. 1C is often referred to as a one-hour discharge; a 0.5 would be a two-hour, and a 0.1C a 10
hour discharge.
Restrictions
• A battery which has completely run down can not be re-charged quickly because the battery voltage
is less than 3.0V and the logic which implements the charge control cannot be operated at this low
voltage level. In this case the battery is recharged via trickle-charging. However, the charging
symbol cannot be shown in the display because at this time logic supply voltages are not operating.
The charging time for this trickle-charging (until the battery can be fast-charged from then on) is in
the range of 1 hour. If, within this time, the battery voltage exceeds 3.2V, then the
ASIC
switches on the mobile and charging continues in the Charge-Only Mode. In some
circumstances it can happen that after trickle-charging and the usually initiated switch-on procedure
of the mobile, the supply voltage collapses so much that the mobile phone switches off again. In this
case trickle charging starts again with a now raised threshold voltage of 3.75V instead of 3.2V, at
maximum for 20 minutes. The
(within 60 minutes overall).
Charging the battery will not be fully supported in case of using old accessory (generation '45' or
earlier). It is not recommended to use any cables that adapt "old" to "new" Lumberg connector. Using
such adapters with Marlin will have at least the following impact:
1) half-sine wave chargers (e.g. P35 & home station) can not be used for trickle
charging
2) normal charging might be aborted before the battery is fully charged
3) EMC compliance can not be guaranteed
• A phone with a fully charged LiIon battery will not be charged immediately after switch-on. Any input
current would cause an increase of the battery voltage above the maximum permissible value. As
soon as the battery has been discharged to a level of about 95% (due to current consumption while
use), it will be re-charged in normal charging mode.
• The phone cannot be operated without a battery.
• The
phone
will
⇒ design-wise it is impossible to wrongly pole the phone. This is prevented by mechanical means.
⇒ electrically, a correctly poled battery is presumed, i.e. correct polarity must be guaranteed by
suitable QA measures at the supplier
• The mobile phone might be destroyed by connecting an unsuitable charger:
⇒ a charger voltage >15V can destroy resistances or capacitors
⇒ a charger voltage >20V can destroy the switch transistor of the charging circuit
In case the transistor fails the ASIC will be destroyed. In the case of voltages lower than 15V and an
improper current limitation the battery might be permanently damaged. A protection against grossly
negligent use by the customer (e.g. direct connection of the charge contact to the electricity supply in
a motor car) is not provided. Customer safety will not be affected by this restriction.
V 1.10
A52/A55/C55 IFX
POWER SUPPLY ASIC
be
destroyed
if
the
Page 36of 45
Company Confidential © Copyright Siemens AG
will retry switching on the phone up to 3 times
battery
is
inserted
POWER SUPPLY
ASIC.
POWER SUPPLY
with
reversed
polarity:
ICM MP CCQ GRM
08/03

Advertisement

Table of Contents
loading

This manual is also suitable for:

A52C55 ifx

Table of Contents