Nokia 3105 Servicehandbuch
CCS Technical Documentation
Troubleshooting — BB
RH-48
Issue 1 11/2003
© 2003 Nokia Corporation Confidential
Page 9
in the active mode depending on the phone present state of the phone such as: burst
reception, burst transmission, if DSP is working, etc.
reception, burst transmission, if DSP is working, etc.
In active mode SW controls the UEM RF regulators: VR1A and VR1B can be enabled or
disabled. VSIM can be enabled or disabled and its output voltage can be programmed to
be 1.8V or 3.3V. VR2 and VR4 -VR7 can be enabled or disabled or forced into low quies-
cent current mode. VR3 is always enabled in active mode and disabled during Sleep
mode and cannot be control by SW in the same way as the other regulators. VR3 will
only turn off if both processors request to be in sleep mode.
disabled. VSIM can be enabled or disabled and its output voltage can be programmed to
be 1.8V or 3.3V. VR2 and VR4 -VR7 can be enabled or disabled or forced into low quies-
cent current mode. VR3 is always enabled in active mode and disabled during Sleep
mode and cannot be control by SW in the same way as the other regulators. VR3 will
only turn off if both processors request to be in sleep mode.
In the CHARGING mode, the charging can be performed in parallel with any other oper-
ating mode. A BSI resistor inside the battery pack indicates the battery type/size. The
resistor value corresponds to a specific battery capacity. This capacity value is related to
the battery technology.
resistor value corresponds to a specific battery capacity. This capacity value is related to
the battery technology.
The battery voltage, temperature, size, and charging current are measured by the UEM,
and the charging software running in the UPP controls it.
and the charging software running in the UPP controls it.
The charging control circuitry (CHACON) inside the UEM controls the charging current
delivered from the charger to the battery and phone. The battery voltage rise is limited
by turning the UEM switch off, when the battery voltage has reached 4.2 V. Charging
current is monitored by measuring the voltage drop across a 220 mOhm resistor.
delivered from the charger to the battery and phone. The battery voltage rise is limited
by turning the UEM switch off, when the battery voltage has reached 4.2 V. Charging
current is monitored by measuring the voltage drop across a 220 mOhm resistor.
Power Distribution
In normal operation, the baseband is powered from the phone‘s battery. The battery con-
sists of one Lithium-Ion cell capacity of 850 mAh, and some safety and protection cir-
cuits to prevent harm to the battery.
sists of one Lithium-Ion cell capacity of 850 mAh, and some safety and protection cir-
cuits to prevent harm to the battery.
The UEM ASIC controls the power distribution to the whole phone through the BB and RF
regulators excluding the power amplifier (PA), which has a continuous power rail directly
from the battery. The battery feeds power directly to the following parts of the system:
UEM, PA, buzzer, vibra, display, and keyboard lights.
regulators excluding the power amplifier (PA), which has a continuous power rail directly
from the battery. The battery feeds power directly to the following parts of the system:
UEM, PA, buzzer, vibra, display, and keyboard lights.
The heart of the power distribution to the phone is the power control block inside UEM.
It includes all the voltage regulators and feeds the power to the whole system. UEM han-
dles hardware functions of power up so that regulators are not powered and power up
reset (PURX) are not released if battery voltage is less than 3 V.
It includes all the voltage regulators and feeds the power to the whole system. UEM han-
dles hardware functions of power up so that regulators are not powered and power up
reset (PURX) are not released if battery voltage is less than 3 V.
RH-48 Baseband is powered from five different UEM regulators (VANA, VIO, VFLASH1,
VFLASH2, and VCORE (DC/DC) See Table 1.
VFLASH2, and VCORE (DC/DC) See Table 1.
UEM supplies also voltages VR1A, VR1B, VR2, VR3, VR4, VR5, VR6, and VR7 for RF. See
Table 2.
Table 2.