User's Manual

MC46 Hardware Interface Description
DRAFT
MC46_HD_V02.8xb Page 40 of 98 21.08.2003
What to do if software controlled charging does not start up?
If trickle charging fails to raise the battery voltage to 3.2V within 60 minutes +
10%, processor
controlled charging does not begin. To start fast charging you can do one of the following:
· Once the voltage has risen above its minimum of 3V, you can try to start software
controlled charging by pulling the /IGT line to ground.
· If the voltage is still below 3V, driving the /IGT line to ground switches the timer off.
Without the timer running, MC46 will not proceed to software controlled charging. To
restart the timer you are required to shortly disconnect and reconnect the charger.
3.5.3 Operating modes during charging
Of course, the battery can be charged regardless of the engine's operating mode. When the
GSM engine is in Normal mode (SLEEP, IDLE, TALK, GPRS IDLE or GPRS DATA mode), it
remains operational while charging is in progress (provided that sufficient voltage is applied).
The charging process during the Normal mode is referred to as Charge mode.
If the charger is connected to the charger input of the external charging circuit and the
module’s POWER pin while MC46 is in POWER DOWN mode, MC46 goes into Charge-only
mode.
Table 9: Comparison Charge-only and Charge mode
How to activate mode Features
Charge mode
Connect charger to charger input of
external charging circuit and module’s
POWER pin while MC46 is
· operating, e.g. in IDLE or TALK mode
· in SLEEP mode
· Battery can be charged while GSM engine
remains operational and registered to the
GSM network.
· In IDLE and TALK mode, the serial interfaces
are accessible. AT command set can be used
to full extent.
· In the NON-CYCLIC SLEEP mode, the serial
interfaces are not accessible at all. During the
CYCLIC SLEEP mode it can be used as
described in Chapter 3.6.3.
Charge-only mode
Connect charger to charger input of
external charging circuit and module’s
POWER pin while MC46 is
· in POWER DOWN mode
· in Normal mode: Connect charger to
the POWER pin, then enter
AT^SMSO.
IMPORTANT: While trickle charging is in
progress, be sure that the application is
switched off. If the application is fed from
the trickle charge current the module
might be prevented from proceeding to
software controlled charging since the
current would not be sufficient.
· Battery can be charged while GSM engine is
deregistered from GSM network.
· Charging runs smoothly due to constant
current consumption.
· The AT interface is accessible and allows to
use the commands listed below.