Nokia 7088, RM219 Baseband Description and Troubleshooting

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Nokia Customer Care

7088 (RM-219)

Mobile Terminal

Baseband Description and

Troubleshooting

7088 (Flower) Base band Description and Troubleshooting

Contents Page

Introduction............................................................................................................... 4

Baseband and RF Architecture................................................................................ 5

Power Up and Reset................................................................................................ 6

Power Up.......................................................................................................8

Power Key..............................................................................................8

Charger...................................................................................................8

External supply source is detected.........................................................8

Power Off.......................................................................................................8

Power Consumption and Operation Modes...................................................9

Power-off Mode ......................................................................................9

Sleep Mode ............................................................................................9

Active Mode............................................................................................9

Charging Mode....................................................................................... 9

Power Distribution .................................................................................................. 10

Clock Distribution.................................................................................................... 11

TCXO...........................................................................................................12

SLEEP crystal circuit for 32.768 kHz...........................................................14

SBI CLK Interface........................................................................................15

Backend IC and Camera Module Clocks.....................................................16

Flash Programming Error Description.................................................................... 16

Charging Operation................................................................................................ 17

Battery .........................................................................................................17

Charging Circuitry........................................................................................17

Charger Detection........................................................................................18

Charge Control ............................................................................................19

Audio ...................................................................................................................... 19

Keypad ................................................................................................................... 21

Display.................................................................................................................... 21

Camera and Flash Light LED................................................................................. 22

Universal Serial Bus (USB).................................................................................... 22

Accessories............................................................................................................ 24

Charging......................................................................................................24

Headset Detection.......................................................................................24

Data Access.................................................................................................25

UIM CARD.............................................................................................................. 25

7088 (Flower)

Nokia Customer Care Baseband Description and Troubleshooting

Test Points.............................................................................................................. 26

Main Board Top Layer Test Points ...............................................................26

Main Board Bottom Layer Test Points..........................................................27

Sub Board Top Layer Test Points................................................................. 28

Sub Board Bottom Layer Test Points...........................................................29

Troubleshooting...................................................................................................... 30

Mobile Terminal is Dead............................................................................... 31

Flash Memory Faults ...................................................................................32

Power Does Not Stay ON or the Mobile Terminal is Jammed......................33

Charger Faults.............................................................................................34

Audio Faults.................................................................................................35

Display Faults..............................................................................................39

Keypad Faults..............................................................................................40

Keypad Faults..............................................................................................41

Camera Faults.............................................................................................42

Camera Faults.............................................................................................43

7088 (Flower) Base band Description and Troubleshooting

Introduction

The mobile terminal with a CDMA single mode engine (Cellular/ 800) and Qualcomm base band consists of the following ASICs:

 Power Management IC, PM6610 (PM)  Mobile Station Modem processor, MSM6025 (MSM)  RFT6122 and RFR6122 are RF transmitter and receiver IC.  128Mb Flash memory and 64Mb pSRAM memory  Backend IC SPCA552E for image processing

The base band (MSM) is consisted of an ARM7 processor, a CDMA processor, a DFM processor, QDSP & codec, PLL, analog interface for RF and controllers for GPIOs, RUIM, USB & peripheral interfaces, all of which are necessary to complete the entire CDMA base band system. ARM7 processor communicates with external memory, backend IC and LCD through local address & memory buses. A QDSP4000 with codec inside the processing/compression for microphone, receiver (earpiece) and speaker signals. CDMA and DFM processors handle CDMA operation and control the radio chip RFT6122 and RFR6122 through analog interface along with other digital control pins. The RFT6122 and RFR6122 provide direct conversion of RF signal (zero IF) architecture to support the CDMA2000 1X standard. The PM6610 controls the power management for base band & RF system, and battery charging algorithm. The base band architecture supports the power-saving function called “sleep mode”. Sleep mode shuts off the voltage-controlled temperature-compensated crystal oscillator (TCXO), which is used as the system clock source for both the RF and the base band. During sleep mode, the system runs from a 32 kHz crystal and all the RF regulators (VREG_RFTX, VREG_RFRX) are off. The sleep time is determined by network parameters. Sleep mode is entered when both the Mobile Station Modem (MSM) and its internal DSP are in standby mode and the normal TCXO clock is switched off. The mobile terminal is awakened by a timer running from this 32 kHz clock supply. The period of the sleep/ wake up cycle (slotted cycle) is 1.28N seconds, where N=0, 1, 2, depending on the clot cycle index.

Mobile Station Modem (MSM) handles the voice

The mobile terminal supports standard Nokia 2-wire and 3 wire chargers (AC-3, AC-4, DC-4, AC-5, ACP-12, AC-1). However, the 3-wire chargers are treated as 2-wire chargers. The PWM control signal for controlling the 3-wire charger is ignored. The MSM and PM energy management software control the charging.

BL-4B (700 mAh) lithium-ion battery is used as the main power source.

7088 (Flower)

Nokia Customer Care Baseband Description and Troubleshooting

Baseband and RF Architecture

Figure 1: Baseband and RF Block Diagram

7088 (Flower) Base band Description and Troubleshooting

Figure 2: Power Distribution

Power Up and Reset

The PM6610 ASIC controls the power up and reset. The base band (MSM) can be powered up in the following ways:

 Pressing the Power button, which means to ground the KPADPWR_N pin

of the PM (“PHONE_ON” net in schematic).

 Connecting the charger to the charger input.

After receiving one of the above signals, the PM will start to enter reset mode. The watchdog starts, and if the battery voltage is greater than its threshold, (3V), a 6ms delay starts to allow MSM to settle. After this delay elapses, the VERG_MSMC

7088 (Flower)

Nokia Customer Care Baseband Description and Troubleshooting

regulator is enabled. Then, VERG_MSMP, VERG_MSMA & VERG_TCXO regulators are enabled in sequence after MSMC. There is a 120us (4 Sleep Clocks) delays between each regulator’s turning-on. The RESET_N signal (from PM6610 pin “PON_RESET_N” to MSM6025 pin “RESIN_N” in schematic) holds low for another 20ms and is sent to MSM. Resets are generated for the MSM’s internal MCU and its internal DSP, and MSM sends TCXO_ON signal to PM (“TCXO_EN” pin) to enable TCXO. After RESET_N goes high, MSM holds PS_HOLD at low state for 200ms and then drives PS_HOLD to high state. This will keep all regulators at on state in order to complete this power on sequence. PHONE_ON key can be released after PS_HOLD goes high.

The RESOUT_N from MSM is used to reset flash memory during power up and to put the flash memory in power down during sleep mode. All base band regulators are switched on when the PM is powered on. The MSM’s internal watchdog runs and resets during normal operation. If the watchdog expires, it will generate a reset signal to reset to MSM status. Then, MSM drives RESOUT_N low to reset flash memory.

MSM can generate (software control MSM GPIO8) BACKEND_RST_N signal to reset backend IC.

Backend IC can generate LCD_RST_N to reset LCD. Backend IC can generate CAM_RST signal to reset camera module.

Figure 3 represents the PM start-up sequence from reset to power-on.

(PHONE_N)

(RESET_N)

Figure 3: Power-on & off sequence and timing

7088 (Flower) Base band Description and Troubleshooting

Power Up

The mobile terminal can use the power key and a charger to power up.

Power Key

When the power key is pressed, the PM enters the power-up sequence. Pressing the power key causes the KPADPWR_N pin (“PHONE_ON” net in schematic) to GND. The power key is directly connected to the PM. This means that when the power key is pressed, an interrupt will be generated to the MSM in order to power on the MCU. The MCU reads the PM IC’s interrupt register and notifies that it is a KPADPWR_N interrupt. The MCU reads the status of the KPADPWR_N pin using the PM’s (SBI) control bus. If the KPADPWR_N stays low for a certain time, the MCU accepts this as a valid power-on state and continues the software baseband initialization. If the power key does not indicate a valid power-on situation, the MCU powers off the base band.

Charger

Charging is controlled by the start-up charging circuitry in order to detect and start charging in cases the main battery is empty and the PM has no supply.

External supply source is detected

If a valid source is applied to VCHG (pin 1 of PM IC, “VEXT_DC” net) and the battery voltage of VPH_PWR exceeds PM’s valid UVLO (2.5V) threshold, the power-on sequence of PM is initiated and its internal regulators are enabled. UVLO is the minimum voltage required for PM6610 operation. If the entire power-on sequence is successful, the appropriate interrupt from PM will be sent to the MSM. Once the battery voltage rises above 3.0V (min. MSM operation voltage), code starts running on MSM. The MSM reads PM registers to identify the power source and whether battery charging is required. If a valid supply voltage is applied while the PM IC is on, the power-on sequence is skipped. A charging sequence will then be initiated.

Power Off

While the PS_HOLD signal from the MSM is high and the PM IC is in one of its power-on states, the PM continually monitors three events that could trigger a power-off sequence:



The MSM drives the PS_HOLD signal low responding to the pressing of the keypad power button.

 Battery voltage drops below power off threshold (Battery voltage < 3.3 V).  The PM IC die temperature exceeds its “severe” over-temperature threshold.

7088 (Flower)

Nokia Customer Care Baseband Description and Troubleshooting

Power Consumption and Operation Modes

Power-off Mode

In power-off mode, power (VPH_PWR) is supplied to the PM6610, RF PA, vibrator, audio amplifier, keypad backlight LED, LCD backlight booster, flash light booster and regulator to support the application of camera. During this mode, the power consumption is approximately 200 uA.

Sleep Mode

The mobile terminal enters sleep mode only when MSM makes the request to PM6610 through the SBI bus. PM then enters Power Saving Mode, but the VDD_MSMC VDD_MSMP regulators remain in power-on status. The 32.768 kHz crystals are enabled. TCXO buffers are off. All other functions and regulators are controlled individually via SBI and are typically disabled for minimum power dissipation.

It exits the Sleep mode either by the expiration of a sleep clock counter in the PM6610 or by some external interrupt (generated by a charger connection, key press, headset connection, etc.). The TCXO is shut down in sleep mode and the 32.768 kHz sleep clock oscillator is used as a reference clock for the base band.

Active Mode

In active mode, the mobile terminal operates normally. It scans channels, listens to a base station, transmits and processes information. There are several sub-states under the active mode. Depending on the mobile terminal’s current state, there are states such as burst reception, burst transmission, etc.

In active mode, this is a normal operating mode for PM6610 IC. VDD_MSMC, VDD_MSMP, VDD_MSMA, VREG_RUIM, VREG_RFRX, VREG_RFTX, and VREG_TCXO regulators are all turned on. TCXO oscillator is enabled, and TCXO buffers are turned on. All other functions and regulators are controlled individually via SBI.

Charging Mode

Charging mode can function in parallel with any other operating mode. A battery ID resistor inside the battery pack indicates the battery type/ size. The resistor value corresponds to a specific battery capacity. The PM measures the battery voltage,

7088 (Flower) Base band Description and Troubleshooting

temperature, size, and charging current.

The charger control block situated inside the PM controls the charging current delivered from the 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 base band is powered by the mobile terminal‘s battery pack. The battery pack consists of one lithium-ion cell with a capacity of 700 mAh and safety and protection circuits.

The PM6610 IC controls the power distribution to the whole mobile terminal, which includes the base band 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 following PM6610 regulators power the base band:

7088 (Flower)

Nokia Customer Care Baseband Description and Troubleshooting

Regulator

MSMC 150 mA 1.88 V Always enabled except during power-off mode

Rating

Current

Voltage Notes

MSMA 150 mA 2.60 V MSMP 150 mA 2.95 V Always enabled except during power-off mode

RUIM 150 mA 3.00 V Enabled only when RUIM card is used

TCXO 50 mA 2.8 V

Table 1: Base band Regulators

Table 2 includes the PM6610 regulators for the RF.

Regulator

RFRX 150 mA 2.60 V Enabled when the transmitter is on

RFTX 150 mA 2.60 V Enabled when the receiver is on

Rating

Current

Voltage Notes

Enabled only when the system is powered on (Off during sleep and power-off modes)

Table 2: RF Regulators

Clock Distribution

The MSM derives its internal clock from two clock inputs, TCXO and SLEEP Clock.

The main clock signal for the base band generates from TCXO. (Temperature-compensated crystal oscillator). The MSM’s TCXO clock input supports the frequency 19.2 MHz. An integrated PLL and digital divider inside the MSM are used to create the required clock for the system.

The SLEEP Clock provides a 32.768 kHz clock source to drive the MSM controller in sleep mode. At this mode, most of the MSM is powered down and the TCXO is disabled.

The PM includes several clock circuits (Figure 4), whose outputs are used for general housekeeping, MSM and RF functions within the mobile terminal system.

7088 (Flower) Base band Description and Troubleshooting

Figure 4: TCXO & SLEEP_XTAL Block Diagram

TCXO

The MSM device integrates a phase-locked loop from the TCXO clock input.

The PM optimizes TCXO operation that enables and disables appropriate circuits in the proper sequence. The controller is enabled by the TCXO_EN signal from the MSM.

When the selected transition occurs at TCXO_EN, the controller quickly enables the TCXO regulator and the input buffer, and begins counting SLEEP_CLK pulses. Within the initial power on period, the TCXO will be stabilized to its own calibrated frequency. This initial period, in units of 32.768 kHz clock pulses, is programmed into a timer within the controller. When the timer expires, the output buffer is enabled. It synchronizes with the TCXO input such that the TCXO_OUT (MSM_TCXO in schematic) signal is glitch free, only valid TCXO pulses are output.

7088 (Flower)

Nokia Customer Care Baseband Description and Troubleshooting

Figure 5: TCXO Enable Timing Diagram

The input buffer (TCXO_IN) accepts sinusoidal or square wave signals at or near

19.2 MHz. The input buffer (TCXO_IN) is powered from the TCXO regulator while the output buffer is powered by VDD_MSMP.

The regulator of TCXO is turned off after the TCXO_EN signal is removed. Upon power-up, the PM defaults to this SBI-controlled mode with the TCXO defaulted on. This assures the MSM will always have a clock available immediately at power-up even if TCXO_EN is low.

TCXO waveform (19.2MHz)

Figure 6: TCXO Timing at 25

7088 (Flower) Base band Description and Troubleshooting

SLEEP crystal circuit for 32.768 kHz

The 32.768 kHz crystal oscillators is the primary SLEEP clock source when TCXO clocks are disabled to save power.

Figure 7: Sleep CLK Block Diagram

The 32.768 kHz crystal oscillator signal is generated by an external crystal, which is supplemented by a PM internal inverter and buffer.

The crystal oscillator continues to run as long as a valid supply is available, even when the PMIC is powered down. This provides a continuous and accurate 32.768 kHz source. The oscillator halts when power from the external supply and main battery are removed.

The PM includes a circuit that continually monitors the crystal oscillator signal. If the crystal stops oscillating, the PM automatically switches to the RC oscillator and sends an MSM interrupt. Narrow pulses at the SLEEP_CLK output may occur during this switchover. The crystal oscillator dissipates little power, adjusting its bias current to the minimum required to maintain oscillation.

SLEEP Clock waveform (32.768KHz)

7088 (Flower)

Nokia Customer Care Baseband Description and Troubleshooting

Figure 8: Sleep_CLK Timing at 250C

SBI CLK Interface

A 9.6 MHz clock signal is used for DBUS, which is used by the MSM to transfer data between the PMIC and MSM6025.

Figure 9: MSM to PM SBI Timing at 250C

7088 (Flower) Base band Description and Troubleshooting

The system clock is stopped during sleep mode by disabling the VREG_TCXO. The PMIC regulator turns off the TCXO, which is from MSM’s TCXO_ON output signal.

Backend IC and Camera Module Clocks

Figure 10: backend IC and camera module clocks Backend IC (U11) uses external 13MHz crystal (Y210) and internal PLL to generate internal clocks. Backend IC provides 24MHz clock to camera module. Camera module uses the 24MHz clock to generate 12MHz pixel clock.

Flash Programming Error Description

This table describes the errors condition during Flash memory downloading to the mobile terminal.

Description Not Working Properly

Packet Checksum fail ERR: CRC invalid Erase fail Unable to erase device Write fail Write unsuccessfully

Figure 11: Flash Programming Error Description

7088 (Flower)

Nokia Customer Care Baseband Description and Troubleshooting

Charging Operation

Battery

Flower uses a Lithium-Ion cell battery with a capacity of 700 mAh. Inside the

battery, there is a resistor connecting between BSI pin and GND pin for battery ID, MSM reads the BSI pin (via VBATT_ID signal in schematic) to identify the battery size. Different charging algorithms will be used for different battery sizes.

Figure 12: BL-4B battery pack pin order

Charging Circuitry

The PM6610 IC charge control is subject to the charger type and the battery size. External components are needed for electromagnetic compatibility (EMC), and transient protection of the input to the base band module. The charger’s DC input is through the dc-jack connector. This mobile terminal supports AC-3, AC-4, DC-4, AC-5, ACP-12 and AC-1 chargers.

Figure 12: Charging Circuitry

7088 (Flower) Base band Description and Troubleshooting

Charger Detection

Connecting a charger creates a voltage on the VCHG (“VEXT_DC” net in schematic) input of the PM6610. Charging starts when the PM6610 detects the VCHG input voltage level above 3.3V (Min. working voltage of VCHG pin). The VCHG signal of PM is generated to indicate the presence of the charger for the software. The power management (PM) software controls the charger identification/ acceptance. The charger recognition is initiated when the EM software receives a ”charger connected” interrupt. The algorithm basically consists of the following three steps:

1. Check that the system current (the collector current of PNP transistor) is within

safety limits.

2. Check the power consumption of PNP transistor is within safety limits.

3. Check that the charger is within the charger window (voltage and current). If the

charger is accepted and identified, the appropriate charging algorithm will be initiated.

Figure 13: Mobile terminal DC Jack power input circuit.

Figure 14: PNP Charging Control Circuit.

7088 (Flower)

Nokia Customer Care Baseband Description and Troubleshooting

Charge Control

In active mode, charging is controlled by the PM6610’s digital part. Charging voltage and current monitoring are used to limit charging into a safe area. The PM6610 has a MaxPower protection limit at PNP transistor to cut-off charger.

Cut Off MaxPower = 1W

The PM6610 limits the charging voltage to MaxVoltage.

MaxVoltage= 4.25V

The PM6610 limits the total system current (the collector current of PNP transistor) by limiting the maximum power of PNP transistor charge.

Audio

The audio control and processing is provided by the MSM that contains the audio codec, the MCU and DSP blocks. These blocks handle and process the audio data signals. The baseband supports 2 microphone inputs and three receiver (earpiece)/ speaker outputs.

Figure 15: Audio Sending Direction Block Diagram

MIC+ & MIC- are used for the mobile terminal's internal microphone. JACK_MIC+ &

7088 (Flower) Base band Description and Troubleshooting

JACK_MIC- are used for headsets.

The internal microphone (MIC+/-) is differential AC connection to the MSM (MIC1P/N). The headset microphone is single-ended AC connection to the MSM (MIC2P/N).

The MICBIAS output (“MIC_BIAS” signal) is used for internal microphone bias to provide 0.2 mA of current at 1.8 Volts DC. VDD_MSMP (2.95V) regulated voltage from PM IC is used for headset microphone bias.

Figure 16: Audio Receiving Direction Block Diagram RECEIVER+ & RECEIVER- (MSM pins EAR1OP & EAR1ON) differential outputs are used for the mobile terminal's internal receiver. HPH_L (MSM pin EAR2) single-ended output is used for accessory external headset. AUXOP & AUXON differential outputs are used to drive external loudspeaker via external audio power amplifier (U100).

The output power for the differential (EAR1O) output is typically 35 mW for a full-scale +3 dBm0 sine wave into a 32 ohm receiver.

The output power for the single-ended (EAR2) output is typically 8.8 mW for a full-scale +3 dBm0 sine wave into a 32 ohm receiver (earpiece).

The output power for the auxiliary (AUXO) output is typically 1.87 mW for a full-scale +3 dBm0 sine wave into a 600 OHM load.

7088 (Flower)

Nokia Customer Care Baseband Description and Troubleshooting

Keypad

The mobile terminal uses six blue light-emitting diodes (LEDs) for keypad illumination. MSM GPIO42 is used to turn on/off these LEDs.

MSM uses GPIO57 ~ GPIO66 (KYPD_0, KYPD_1, KYPD_3, ~ KYPD_17) to do keypad scan function.

Display

Figure 17: LCD Module Block Diagram

The mobile terminal LCD is 128*160 dot matrix transmissive color TFT LCD.

The LCD module contains three serial white LEDs for LCD backlight. LEDs are driven by a booster (U12). The enable/disable of booster is controlled by BACKLIGHT_EN signal. BACKLIGHT_ADJ signal driven by MSM is used for adjustment of LEDs luminance.

7088 (Flower) Base band Description and Troubleshooting

Camera and Flash Light LED

Figure 18: Camera and Flash Light LED Block Diagram

The mobile terminal has a camera module. The camera module uses CMOS sensor with 640*480 resolution and fixed focus lens. The camera module is connected to backend IC (U11) via camera connector (J21).

Flash light LED is driven by booster (U240). The enable/disable of booster is controlled by backend IC via FLASH_EN signal.

Universal Serial Bus (USB)

Figure 19: USB Block Diagram The mobile terminal has a Universal Serial Bus (USB) interface for data access. The USB interface supports full-speed (12 Mbps) transmission and receiving. It is compliant with the Universal Serial Bus Specification Rev. 2.0.

7088 (Flower)

Nokia Customer Care Baseband Description and Troubleshooting

The following table lists the signals and their functions.

Signal Function

USB_VPO Differential output (+) USB_VMO Differential output (–) USB_RCV Single-ended input from USB transceiver; driven LOW when

input USB_SUSPEND is HIGH;

USB_OE_N An active low output used to enable or disable the D+ and D–

pins of the transceiver.

USB_READY Software controlled USB connection; allows USB connect or

disconnect signaling to be controlled by software USB_SUSPEND Indicating suspending state USB_INSERT_INT VBUS indicator;

“High”: When VBUS > 4.1 V, or USB_SUSPEND = HIGH

“Low”: When VBUS < 3.6 V D+ Positive USB data bus connection (analog, differential) D- Negative USB data bus connection (analog, differential) VBUS USB bus power

7088 (Flower) Base band Description and Troubleshooting

Accessories

The Flower supports the following accessories.

Figure 20: Pop-port bottom connector pin out

The pins out on the Flower connector are as follows:

• DC Charger Input  Blue

• USB port  Purple

• Headset Jack  Green

You can perform the followings on Flower accessories:

• Charging

• Audio interface headset microphone and receiver (earpiece)

• Data access

Charging

This mobile terminal supports AC-3, AC-4, DC-4, AC-5, ACP-12 and AC-1 chargers, and is connected through this interface.

Headset Detection

The mobile terminal supports Nokia standard 2.5mm mono headset. The headset insertion to the mobile terminal is detected by pin 2 of the headset Jack, J701. JACK_SENSE_N signal is low when headset not inserted. It becomes high when headset is inserted.

7088 (Flower)

Nokia Customer Care Baseband Description and Troubleshooting

Figure 21: Headset Detection Circuit

Data Access

This mobile terminal has a USB port. Connect the USB port to a PC. Use the utility program to access the data on mobile terminal.

UIM CARD

This mobile terminal supports UIM Card function. Figure 22 shows the timing of the UIM’s serial interface.

UIM_DATA

UIM_CLK

UIM_REST

VREG_RUIM

Figure 22: UIM Card Serial Timing

7088 (Flower) Base band Description and Troubleshooting

Test Points

Main Board Top Layer Test Points

7088 (Flower)

Nokia Customer Care Baseband Description and Troubleshooting

Main Board Bottom Layer Test Points

7088 (Flower) Base band Description and Troubleshooting

Sub Board Top Layer Test Points

7088 (Flower)

Nokia Customer Care Baseband Description and Troubleshooting

Sub Board Bottom Layer Test Points

7088 (Flower) Base band Description and Troubleshooting

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:

• "Mobile Terminal is Dead"

• "Flash Memory Faults"

• "Power Does Not Stay ON or the Mobile Terminal is Jammed"

• "Charger Faults"

• "Audio Faults"

• "Display Faults"

• "Keypad Faults"

• "Camera Faults"

Note:

• MSM6025 (U625) is under filled and cannot be replaced.

• Memory IC (U6) is under filled and cannot be replaced.

• Backend IC (U11) is under filled and cannot be replaced.

• The Base band Shielding Cover Assy and RF Shielding Cover cannot be reused after removal.

• After using the heat gun, the dome sheet is recommended to be replaced.

7088 (Flower)

Nokia Customer Care Baseband Description and Troubleshooting

Mobile Terminal is Dead

Mobile

Terminal is

Dead

♦ If current is zero, check L101,Q400, R710, F1

and check the power on sequence. If there is no powe r o u t pu t , reheat solder joints o r change PM6610.

Is the mobile

terminal current is

zero or too high?

YES

♦ Make sure all BB regulators are at their respectiv

voltage levels (VDD_MSMA, VDD_MSMP, VDD_MSMC, VREG_TCXO). Reheat solder joints / change PM6610 if necessary.

Is the current

< 60 mA?

YES

Check RESET_N signals. Is it high

(2.8V)?

YES

Check PS_HOLD signals. Is it high

(2.9V)?

Check J101, C108, C109

and R110.

Are they OK?

Reheat solder

joints , check R836

or change PM6610

YES

Is flash memory

programming OK?

YES

Reheat solder joints

change PM6610.

MSM6025 is

defective, phone can

not be repaired and

must be replaced.

Flash

Memory

Faults

Mobile

Terminal is

Jammed

Check LCM_OE_N

(same as OE_N). Is it

toggling after

RESET_N goes high?

YES

Memory IC is

defective, phone can

not be repaired and

must be replaced.

MSM6025 is defective,

phone can not be repaired

and must be replaced.

Issue 1 12/20

7088 (Flower)

Base band Description and Troubleshooting

Flash Memory Faults

Flash

Memory

Faults

Measure 19.2MHz

MSM_TCXO. Is it

YES

Can the mobile

terminal connect to

PC via USB?

YES

Check ROM_CS_N

and WE_N. Are they

toggling during

programming?

Measure the

19.2MHz CLK

coming from the

MSM6025 is defective,

phone can not be repaired

and must be replaced.

Memory IC is

defective, phone can

not be repaired and

must be replaced..

Is it work?

END

MSM6025 is

defective, phone can

not be repaired and

must be replaced.

Check/ change

VREG_TCXO, Y102,

R839, R849, C870, C871, C868, C869,

R853 and C863

Mobile

Terminal is

Jammed

YES

Memory IC is

defective, phone can

not be repaired and

must be replaced.

7088 (Flower)

Nokia Customer Care Baseband Description and Troubleshooting

Power Does Not Stay ON or the Mobile Terminal is Jammed

Mobile

Terminal

Measure VDD_MSMP,

VDD_MSMC,

VDD_MSMA, and

VREG_TCXO voltages.

Are they OK?

YES

Measure 32.768kHz

Sleep CLK. Is it OK?

YES

Measure 19.2MHz

MSM_TCXO. Is it

Check VPH_PWR, VDD_MSMP,

VDD_MSMC, VDD_MSMA, and

VREG_TCXO capacitors. Are

they OK?

YES

Check VBATT_ID

and

VPH_PWR. Are they

Measure the 32.768

Reheat solder joints o

change PM6610

Measure the

19.2MHz CLK

coming from the

Reheat solder

joints or

PM6610

hange Y1

Check/ reheat solder

joints/ change

VREG_TCXO, Y102,

R839, R849, C870,

C871, C868 and

Repair capacitors, reheat

solder joints/ change

TCXO(Y102) and PM6610

change

C869.

YES

MSM6025 is

defective, phone can

not be repaired and

must be replaced.

Measure RESET_N.

Is it high (2.8V)?

YES

Reheat solder joints

or chan

e PM6610

MSM6025 is

defective, phone can

not be repaired and

must be replaced.

7088 (Flower)

Base band Description and Troubleshooting

Charger Faults

Charge

Faults

Connect the charger

and make sure the

battery is

connected.

Check

BATT_ID. Is it

about 75k Ohm or 81k

Ohm in battery?

YES

Measure voltage at

VEXT_DC (TP161).

Is it >4.5V?

YES

Read MOBILE

TERMINAL_THERM

value. Is it room

temperature?

YES YES

Check/ change DC

Jack, C108, C109,

R110 and

VDD_MSMA.

Check/ change DC Jack,

F1, L101, D1006, D1007,

C1030, C874, R864 and

Q400.

Check NTC R4021and

NO NO

R300. Are they OK?

MSM6025 is defective,

phone can not be

repaired and must be

replaced.

Replace

NTCR4021,

R300

Measure voltage

between pin#1 and pin#3

of Q400. Is it >0.7V

YES

Change Q400

Check R851.

Is it OK?

YES

Reheat solder joints or

change PM 6610

Reheat solder joints/

change R851

nfidential Issue 1 12/20

7088 (Flower)

Nokia Customer Care Baseband Description and Troubleshooting

Audio Faults

Audio

Faults 1

Is the on-board

receiver working?

YES

Replace the

receiver

(earpiece). Is it

working now?

Use CCS Service

Software

Audio/Vibra



TestingStereo



Receiver Mobile

terminal Receiver Loop Back

Test command

Is the signal coming out of the

MSM6025

on RECEIVER+ and

RECEIVER- ?

YES

Retest

Check/ change R511, R512,

C427, C426, C425, D421 and

D422 . Is it OK?

YES

Audio Faults

Page 2

MSM6025 is defective, phone can not be repaired and must

be replaced.

Change the receive

7088 (Flower)

Base band Description and Troubleshooting

Audio

Faults 2

Is onboard

microphone

working?

YES

Replace the

microphone. Is it

workin

now?

Use CCS Software



Testing



Stereo Audio/Vibra



MicrophoneMobile terminal Microphone Test command

Measure microphone bias voltage at

pin 1 of microphone. Is it 1.3V~ 1.5V?

YES

Is the signal going to the MSM6025

between MIC+ and MIC- ?

YES

Retest

change R716,

Check

C701 and R717. If OK,

MSM6025 is

defective, phone can

not be repaired and

must be replaced.

Check/ change C713,

C706, C707, D410 and

D411. If OK,

MSM6025 is

defective, phone can

not be repaired and

must be replaced.

Audio

Retest

Faults

Page 3

7088 (Flower)

Nokia Customer Care Baseband Description and Troubleshooting

Audio

Faults 3

Is the internal

handsfree speaker

working?

YES

Audio

Faults

Page 4

Select a ring tone and

measure signal between

J424 Pin1 and Pin2. Is the

signal OK?

Measure AUDIO_EN

(AUDIO_ENABLE on main

board). Is it OK (2.9V)?

YES

Measure signal between

SPK_N and SPK_P . Is the

signal OK?

Check/ change R173, C171,

C172,C174 and C175.R175~R1 78.

Check VPH_PWR. Are the signals

OK?

YES

Replace U100 and retest.

YES

Yes

Change speake

MSM6025 is

defective, phone

can not be repaired

and must be

replaced.

Check/changeL815, L816,C509,C510,C5

11,C512.

7088 (Flower)

Base band Description and Troubleshooting

Audio

Faults 4

Use CCS

Is the vibrator

working?

YES

Software Audio/Vibra Control Test Command Measure the VIB_DRV signal on the vibrator. Is the signal OK?



Testing Stereo



Vibrator

YES

Check CR01

and C25. Are

they OK?

YES

Change and

retest

END

Change the vibrato

Change PM 6610

7088 (Flower)

Nokia Customer Care Baseband Description and Troubleshooting

Display Faults

Display

Faults

Do the backlight

LEDs turned on

when the mobile

terminal is turned

on or when making

a call?

YES

Check voltage across

L122_pin1 > 9V. Is it OK?

Measure battery voltage

D121 pin1. Is it OK?

YES

Check/change D121, L123,and R127. Is each one OK?

YES

Measure BACKLIGHT_EN

at U12_pin4. Is it high?

YES

Yes

Check R126. If OK,

replace LCD Module

Check/ change

battery, VPH_PWR

and check FPC

connection.

Replace the

component and

retest

Check C233. If OK,

MSM6025 is defective,

phone can not be repaired

and must be replaced.

Check U12_pin1. Does it

switch between 0V and

YES

Check BACKLIGHT_ADJ

< 0.263 V. Is it OK?

Replace U12 and

retest.

Check D417

Display

YES

Faults 2

Replace U12 and retest

7088 (Flower) Base band Description and Troubleshooting

Display

Faults Page2

Does LCD display

start?

YES

Display

Faults 3

NO NO

and D_VDD (1.88V). Is each

one OK?

Check power IO_VDD (2.95V)

YES

Check power

TFT_VDD_MSMP(2.95V),I s it

ok?

YES

Check/change U20,U21,U22

and FPC connection

J31.Check LCD

signals:TFT_MAIN_CS,TFT_R

S,TFT_WE and LCD_RST, are

they ok?

YES

Check/change FPC connection(J41A) and PM6610

Replace L411 and

retest

Backend IC is

defective. Phone

can not be repaired

and must be

replaced

LCD is defective. Replace

LCD Module board

7088 (Flower)

Nokia Customer Care Baseband Description and Troubleshooting

Keypad Faults

Keypad

Faults

Measure voltage at PHONE_ON (TP221 on main board and

Is the power

key working?

NO NO

TP2221 on sub

board) (2.8V).

Check FPC

Connention. If OK,

change PM6610

YES

Keypad

Faults

Page 2

YES

Measure voltage at

PHONE_ON when

power key is pressed.

Is it Low?

Replace

Keymat

YES

Retest

7088 (Flower)

Base band Description and Troubleshooting

Keypad

Faults

Page 2

Check/change D350 and

D351.Then retest.

YES

Measure KYPD_(0,1,3,5,7)

Are the keys

working?

YES

signals between MSM6025

and keypad at every outer

dome key. Are they ~ 2.9V?

YES

Measure

KYPD_(9,11,13,15,17)

signals between

MSM6025 and keypad

on every inner dome

Key. Are they about

Make sure there are no shorts

on KYPD_(0,1,3,5,7)?

MSM6025 is defective can

not be repaired and must be

replaced

Make sure there are no shorts

on KYPD_(9,11,13,15,17)?

YES

END

YES

MSM6025 is defective,

phone can not be

repaired and must be

laced

Check/change D352~D354(on

main board), then retest.

7088 (Flower)

Nokia Customer Care Baseband Description and Troubleshooting

Camera Faults

Camera

Faults

Can the camera preview?

Unplug camera and

check camera

socket(J21) connection, then plug the camera.

Can the camera

preview?

Yes

Retest

Yes

Take a picture. Does the picture is blurred?

Yes

Check power

D_VDD (~1.88VV)

Is it OK?

YES

Check power

IO_VDD (~2.95V)

Is it OK?

YES

Check power

A_VDD (~2.7V)

Is it OK?

YES

Check signals

CAM_RST,

CAM_PWDN,

CAM_XCLK,

CAM_SDATA and

CAM_SCK. Are the

signals OK?

Check/ change

L413

Check/ change

L411

Check/ change

U23,C221,

C222,C224 and

R226. And check

VPH_PWR

Backend IC is

defective. Phone

can not be repaired

and must be

replaced.

YES

END

Replace camera

module and retest.

7088 (Flower) Base band Description and Troubleshooting

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Nokia 7088, RM219 Baseband Description and Troubleshooting

Specifications and Main Features

Frequently Asked Questions

User Manual

Contents Page

Baseband and RF Architecture

Power Up and Reset

Power Up

Power Key

Charger

External supply source is detected

Power Off

Power Consumption and Operation Modes

Power-off Mode

Sleep Mode

Active Mode

Charging Mode

Power Distribution

Clock Distribution

TCXO

SLEEP crystal circuit for 32.768 kHz

SBI CLK Interface

Backend IC and Camera Module Clocks

Flash Programming Error Description

Charging Operation

Battery

Charging Circuitry

Charger Detection

Charge Control

Audio

Keypad

Display

Camera and Flash Light LED

Universal Serial Bus (USB)

Accessories

Charging

Headset Detection

Data Access

UIM CARD

Test Points

Main Board Top Layer Test Points

Main Board Bottom Layer Test Points

Sub Board Top Layer Test Points

Sub Board Bottom Layer Test Points

Troubleshooting

Mobile Terminal is Dead

Flash Memory Faults

Power Does Not Stay ON or the Mobile Terminal is Jammed

Charger Faults

Audio Faults

Display Faults