Power Distribution - Nokia 6088 Baseband Description And Troubleshooting

6088 (RM218)
Baseband Description and Troubleshooting
charger to the battery and mobile terminal. The maximum battery voltage is limited
by turning the PM switch off when the battery voltage reaches 4.2 V. The charging
current is monitored by measuring the voltage drop across a 0.1 ohm resistor.

Power Distribution

In normal operation, the baseband is powered by the mobile terminal's battery pack.
The battery pack consists of one lithium-ion cell with a capacity of 820 mAh and
safety and protection circuits.
The PM6610 IC controls the power distribution to the whole mobile terminal, which
includes the baseband and the RF regulators, but excludes the RF power amplifier
(RF PA) RF power amplifier drains power from the battery directly. The battery
provides power directly to the following parts of the system:
PM6610
RF PA
Vibrator
Keyboard & LCD backlights
Audio Amplifier
Flash light
Regulator for camera
The heart of the power distribution is the power control block inside the PM6610. It
includes all the voltage regulators and feeds the power to the entire system. The
PM6610 handles hardware power-up functions so that the regulators are not
powered on and the power up reset (PURX) is not released if the battery voltage is
less than 3 V.
The baseband is powered by the following PM6610 regulators:
Rating
Regulator
Current
MSMC 150 mA
MSMA 150 mA
MSMP 150 mA
RUIM 150 mA
TCXO 50 mA
Page 10 © 2006 Nokia Corporation
Voltage Notes
1.88 V Always enabled except during power-off mode
Enabled only when the system is powered on
2.60 V
(Off during sleep and power-off modes)
2.95 V Always enabled except during power-off mode
3.00 V Enabled only when RUIM card is used
Enabled only when the system is powered on
2.85 V
(Off during sleep and power-off modes)
Table 1: Baseband Regulators
Company Confidential Issue 1 10/2006