CCS Technical Documentation
System Module and User Interface
NSB-9
Issue 1 04/03
Nokia Corporation
Page 27
Power up when battery is connected
Baseband can be powered up by connecting battery with sufficient voltage. Battery volt-
age has to be over UEM internal comparator threshold level, Vcoff+. Battery low limit is
specified in Table 2. When proper battery voltage is detected UEM enters to reset
sequence as described earlier.
RTC alarm power up
If phone is in POWER_OFF mode when RTC alarm occurs the wake up procedure is as
described in section 5.5. After baseband is powered on an interrupt is given to MCU.
When RTC alarm occurs during ACTIVE mode the interrupt for MCU is generated.
A/D Channels
The UEM contains the following A/D converter channels that are used for several mea-
surement purposes. The general slow A/D converter is a 10 bit converter using the the
UEM interface clock for the conversion. An interrupt will be given at the end of the mea-
surement.
The UEM’s 11-channel analog to digital converter is used to monitor charging functions,
battery functions, voltage levels in external accessory detection inputs, user interface
and RF functions.
The monitored battery functions are battery voltage (VBATADC), battery type (BSI) and
battery temperature (BTEMP) indication.
The battery type is recognized through a resistive voltage divider. In phone there is a
100kOhm pull up resistor in the BSI line and the battery has a pull down resistor in the
same line. Depending on the battery type the pull down resistor value is changed. The
battery temperature is measured equivalently except that the battery has a NTC pull
down resistor in the BTEMP line.
KEYB1&2 inputs are used for keyboard scanning purposes. These inputs are also routed
internally to the miscellaneous block. In NSB-9 KEYB1 input is used for flip position
detection.
The HEADINT and HOOKINT are external accessory detection inputs used for monitoring
voltage levels in these inputs. They are routed internally from the miscellaneous block
and they are connected to the converter through a 2/1 multiplexer. HOOKINT is not used
in NSB-9. HEADINT is connected to System Connector ACI line, and it is switched inside
the UEM to MBUS line.
The monitored RF functions are PATEMP and VCXOTEMP detection. PATEMP input is used
to measure temperature of the HAGAR RFIC. VCXOTEMP is not used in NSB-9.