Nokia 1508I User manual

1508i(RM-430)
Baseband Description and Troubleshooting
Nokia Customer Care
Issue 1
Copyright © 2008 Nokia, All rights reserved
Nokia Customer Care
1508i (RM-430)
Mobile Terminal
Baseband Description and
Troubleshooting

1508i(RM-430)
Baseband Description and Troubleshooting
Nokia Customer
Care
Issue 1
Copyright © 2008 Nokia, All rights reserved
Contents
BB Troubleshooting 1508i

1508i(RM-430)
Baseband Description and Troubleshooting
Nokia Customer
Care
Issue 1
Copyright © 2008 Nokia, All rights reserved
1508i system brief introduction
1508i main features
1508i is a CDMA phone based on the VIA platform.
1) CDMA PCS support only
2) FM stereo radio
3) Compliance to USB 2.0 (full speed)
4) R-UIM card
The main devices
Device Model number Supplier
Baseband processor CBP 5.6 VIA
PMU ACT5805 Active
Memory S71GL064NB0BFW0Z0 SPANSION
LCD BYD4205T BYD
FM Stereo radio Si4702-B16-GM SILICON LABS

1508i(RM-430)
Baseband Description and Troubleshooting
Nokia Customer
Care
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Copyright © 2008 Nokia, All rights reserved
Figure 1 Component layout (Bottom)

1508i(RM-430)
Baseband Description and Troubleshooting
Nokia Customer
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System Block Diagram
System Description
1508i is a CDMA (PCS band) Mobile Phone. The phone supports:
- forward and reverse link data rates of up to 153.6kbps.
- 4GV vocoder
- 1.47”(128*128) CSTN LCD
- Stereo FM radio
Platform Introductions
CBP 5.6
VIA Telecom’s CBP 5.6 single-chip CDMA Base Band
Processors provide a complete 3G CDMA2000® 1X
(Release 0) solution. They are designed to meet or exceed

1508i(RM-430)
Baseband Description and Troubleshooting
Nokia Customer
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the specifications of mobile stations for worldwide 3G CDMA
systems as specified by CDMA2000® 1X (Release 0)
standards and are backward-compatible to IS -95.
CBP 5.6 integrates three processor subsystems:
ARM7TDMI® Control Processor (CP) supports the protocol
stack, user interface, and hardware interface processing.
Two TeakLite® Digital Signal Processors (DSPs): one DSP
supports CDMA modem processing, the second DSP
supports CDMA voice processing
The main features of the CBP 5.6
zSupports CDMA2000® 1X (Release 0)
zBackward compatible to IS-95 standards
zSupports IS-2000 Quick Paging Channel for improved standby time
zSupport for multiple CDMA band classes (Band Class 0/US-Cellular,
Band Class 1/US-PCS, Band Class 3/JTACS, Band Class 4/Korean-
PCS); support for additional band classes which can be added upon
customer request
zSpecial purpose logic provides signal processing, modulation,
demodulation, hardware accelerators and interfaces for keypad and
display
zMixed signal circuitry for the Rx analog-to-digital converter (ADC), Rx
filter, Tx digital-to-analog converter (DAC), Tx filter, internal PLLs,
voice codec, auxiliary ADCs, auxiliary DACs, RF control and 32.768
kHz oscillator
zSupport for forward and reverse link data rates of up to 153.6 kbps
(CBP5.6 only).
z Dual supply voltage (1.8 V digital core, 3.0 V analog and 3.0 V digital
I/O)
z3.0 V or 1.8 V external memory interface

1508i(RM-430)
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zUSB support (12 Mbps)
zRemovable User Identity Module (R-UIM) compliant with IS-820
z32-voice polyphonic ringer

1508i(RM-430)
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The interface of the CBP5.6 is described in the following
diagram. Receive and transmit interfaces for CBP 5.6
provide analog I and Q signals and support super-
heterodyne radio and direct conversion radio design. The
CP external-memory interface supports 3.0V or 1.8V, the
address bus supports 16-bit address which can support
three to six external devices via chip selects. CBP 5.6
includes 48 GPIOs and interrupts, some of which are
multiplexed with other functions. All GPIO pins are in input
state by default and use a large pull-up or pull-down resistor
value to minimize the current drain. The USB port supports
data rates of up to 12Mbps, the USB analog drivers and
48.00MHz PLL are integrated into CBP 5.6, the control
processor manages the USB function. Two independent
serial-peripheral interfaces are provided on CBP 5.6: one is
for RF control and the other is for general-purpose use. The
R-UIM interface supports 3V UIM cards and consists of five
pins, these pins are multiplexed with another function. The
CP manages the R-UIM function.
Five independent PDM DACs are supplied on the CBP 5.6
chip.
Three of the outputs are dedicated to radio-control signals
for Rx automatic gain control (AGC), Tx AGC, and automatic
frequency control (AFC). The fourth and fifth PDM outputs
are spares. The PDMs are 12-bit DACs and have a
guaranteed output range of 0.2 V to 2.5 V.
The 12-bit auxiliary ADC supports eight independent
external channels on pins AUXADC [7:0]. There are also
eight internal channels used to measure internal analog
voltages. The input voltage range is 0.2 V to 2.7 V. The
conversion time is 156 µsec. The typical uses of the external

1508i(RM-430)
Baseband Description and Troubleshooting
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auxiliary ADC channels include: Tx RF power measurement,
battery voltage, and temperature sensors.
The baseband is powered by the following PMU ACT5805 regulators:
VDD_DIG = 3.0v
VDD_CORE = 1.8v
VDD_TXPLL = 3.0v
VDD_TCXO = 3.0v
VDD_ANALOG =3.0v
VDD_RX = 3.0v
VDD_TX = 3.0v
VIB_P=2.8v~3.6v

1508i(RM-430)
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Power Up
The mobile terminal uses the power key and a charger to power up.
Power Key
When the power key is pressed, the PMU enters the power-up sequence.
Pressing the power key causes the POWER_ON pin to VBAT. The
POWER_ON signal is not part of the keypad matrix. The power key is
connected to the PMU. This means that when the power key is pressed, an
interrupt will be generated to the CBP in order to power on the CBP. The CBP

1508i(RM-430)
Baseband Description and Troubleshooting
Nokia Customer
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reads the PMU IC’s interrupt register and notifies that it is a KPADPWR_N
interrupt. The CBP reads the status of the POWER_ON signal using the
PMU’s (I2C) control bus. If the POWER_ON signal stays High for a certain
time, the CBP accepts this as a valid power-on state and continues with the
software baseband initialization. If the power key does not indicate a valid
power-on situation, the CBP powers off the baseband.
Charger
Charging is controlled by start-up charging circuitry in order to detect and start
charging in case the main battery is not full and the PMU has no supply.
Power Off
While the PS_HOLD signal from the CBP is high, and the PMU IC is in
power-on status. The PMU continually monitors three events that could
trigger a power-off sequence:
zThe CBP drives the PS_HOLD signal low responding to the pressing
of the keypad power button.
zBattery voltage drops below power off threshold (Battery Voltage <
3.2V).
zThe PMU IC die temperature exceeds its “severe” over-temperature
threshold.
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 860 mA and safety and protection circuits.
The PMU ACT5805 IC controls the power distribution for the whole mobile
terminal, which includes the baseband and the RF regulators, but excludes
the RF power amplifier (RF PA) which drains power from the battery

1508i(RM-430)
Baseband Description and Troubleshooting
Nokia Customer
Care
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directly. The battery provides power directly to the following parts of the
system:
· PMU ACT5805
· RF PA
· Vibrator
· Keyboard & LCD backlights
· Audio Amplifier
The heart of the power distribution is the power control block inside the
PMU ACT5805. It includes all the voltage regulators and feeds the power
to the entire system. The PMU ACT5805 handles hardware power-up
functions so that the regulators are not powered on and the power up reset
(NRST) is not released if the battery voltage is less than 3.2 V.
The baseband is powered by the following PMU ACT5805 regulators:
Regulator Voltage
Rating
Current
Notes
VDD_DIG 3V 250mA
Always enabled except during
power-off mode
VDD_CORE 1.8V 150mA
Enabled only when the system is
powered on (Off during sleep and
power-off modes)
VDD_TXPLL 3.0V 80mA
Enabled only when the
transmitter is on
VDD_TCXO 3.0V 80mA
Enabled only when the system is
powered on (Off during sleep and
power-off modes)
KEYPAD_LED 3.0V 100mA
Enabled when the system is
powered on, or the keys are

1508i(RM-430)
Baseband Description and Troubleshooting
Nokia Customer
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pressed,etc.
VDD_RX 3.0V 80mA Enabled when the receiver is on
VDD_TX 3.0V 150mA
Enabled when the transmitter is
on
VDD_VIBE 3.0V 150mA
Enabled only when the system is
powered on (Off during sleep and
power-off modes)
Clock Distribution
The CBP derives its internal clock from two clock inputs, TCXO and
SLEEP_CLK.
The main clock signal for the baseband is generated from TCXO.
(Temperature-compensated crystal oscillator) The CBP’s TCXO clock
input supports the frequency 19.2 MHz +/-2ppm. An integrated PLL and
digital divider inside the CBP are used to create the required clock for the
system.
The SLEEP_CLK provides a 32.768 kHz +/-20ppm clock source to drive
the CBP controller into sleep mode. At this mode, the TCXO is disabled.
TCXO
The CBP device integrates a phase-locked loop from the TCXO clock
input.
The PMU optimizes TCXO operation that enables and disables
appropriate circuits in the proper sequence. The controller is enabled by
the OSC_EN signal from the CBP. .
SLEEP Crystal Circuit for 32.768 kHz
The 32.768 kHz crystal oscillator is the primary SLEEP clock source when TCXO
clocks are disabled to save power.

1508i(RM-430)
Baseband Description and Troubleshooting
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Charging Operation
Battery
The 1508i uses a Lithium-Ion cell battery with a capacity of 860mA.CBP
reads the resistor inside the battery pack on the BSI line to identify the
battery size. Different charging algorithm will be used for different battery
sizes. The resistors are connected to the BSI pin inside the battery
connector.
BSI= BATT_DET
Charging Circuitry

1508i(RM-430)
Baseband Description and Troubleshooting
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Display and Keypad
The mobile terminal uses light-emitting diodes (LEDs) for liquid crystal display
(LCD) and keypad illumination. There are two white LEDs for the LCD and two
LEDs for the keypad. KEYPAD_LED is the signal used to drive keypad LEDs.
LCD_BL_EN is the signal used to drive LCD LEDs. The mobile terminal uses a
color LCD. The interface uses a parallel bus to transfer the Command/ Data
between CBP and LCD.
Troubleshooting
First, carry out a thorough visual check of the module. Make sure in
particular that:
• There is no mechanical damage.
• Soldered joints are OK.
• ASIC orientations are OK.
The following hints should help find the cause of the problem when the
circuitry seems to be faulty. Troubleshooting instructions are divided into
the following sections:

1508i(RM-430)
Baseband Description and Troubleshooting
Nokia Customer
Care
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·‘Power Does Not Stay ON’
·“Charger Faults’
·‘Audio Faults’
·‘Display Faults’
·‘Keypad Faults’
·‘No Vibration’
·‘Series/USB Interface Disabled’
·‘UIM Card Unreadable’
Note:
• CBP5.6 is underfilled and can not be replaced.
• The Shielding Case Assy can not be reused after removal.
• After using the heatgun, the domesheet needs to be replaced.

1508i(RM-430)
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Repair Function in Power-off Status (refer to PMU Circuit)
•The current status resulting ‘Power Off” could be divided into three
cases:
•Big current, no current, no holding current.
Case One.
Big current appears when power is fed to Vbattery or “power on” key is
pressed on the handset.
Check if the following voltages of PMU are normal: VDD_DIG,
VDD_CORE, VDD_TXPLL, VDD_TCXO, VDD_RX, VDD_TX,
If the voltages are abnormal, check the fault reason.
Case Two.
If current is zero, check CN703and
C1011,C1012,C1013,C1014,C1015,C1016.If there is no power output,
PMU is defective. Phone cannot be repaired and must be replaced.
Case Three.
Raise the voltage of PS-HOLD, and measure every output voltage of PMU,
The reference clock Power-on needed is KHZ.19.2MHZ etc.
such
as :VDD_DIG,VDD_CORE,VDD_TXPLL,VDD_TCXO,VDD_RX,VDD_TX ;
Check if the clock TCXO（19.2MHz）and RTC（32.768KHz）are normal.
If the signals are abnormal, please check the fault reason;
If it is normal, please check the welding of CPU and Flash and perform
welding or replacement. (Replacement includes Flash Updating).The
welding of the display panel connector should also be checked, because
the shortcut of the parallel data signal and Read & Write signal on the
display panel connector will lead to failure of CPU in invoking the
programs of FLASH.

1508i(RM-430)
Baseband Description and Troubleshooting
Nokia Customer
Care
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Copyright © 2008 Nokia, All rights reserved
Power Does Not Stay ON Troubleshooting

1508i(RM-430)
Baseband Description and Troubleshooting
Nokia Customer
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PMUACT5805 circuits

1508i(RM-430)
Baseband Description and Troubleshooting
Nokia Customer
Care
Issue 1
Copyright © 2008 Nokia, All rights reserved