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NSD-6
Cover
5 pgs46.6 Kb0
Disassembly
44 pgs1.31 Mb0
General Information
10 pgs192.4 Kb0
Nonserviceable Accessories
26 pgs235.44 Kb0
Schema
12 pgs912.54 Kb0
Service Software
90 pgs1.17 Mb0
Service tools
26 pgs277 Kb0
System Module
86 pgs1.11 Mb0
UI Module
16 pgs154.25 Kb0
Vari Antenna Description and Troubleshooting
8 pgs72.61 Kb1
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Nokia NSD-6, 3280, 3285 Disassembly

Programmes After Market Services
NSD-6 Series Transceivers
Disassembly/Troubleshooting
Instructions
Issue 1 04/01 Nokia Mobile Phones Ltd.
NSD-6
Disassembly/Troubleshooting Instructions PAMS Technical Documentation
Page 2 Nokia Mobile Phones Ltd. Issue 1 04/01
NSD-6
Contents
Page No
Troubleshooting ............................................................................................................. 8
Baseband Troubleshooting............................................................................................. 8
Main Circuit Sections..................................................................................................... 8
Power Circuitry ............................................................................................................8
CCONT ........................................................................................................................8
Vbat ..............................................................................................................................8
Vref ..............................................................................................................................8
Linear Regulators .........................................................................................................9
1. Vbb........................................................................................................................ 9
2. RF Regulators (VR1–VR7)................................................................................... 9
3. V2V (VMAD) ....................................................................................................... 9
Switch mode regulator .................................................................................................9
1. V5V (+5V_POWER) ............................................................................................ 9
2. VSIM (3V_5V) ..................................................................................................... 9
A/D Conversion....................................................................................................... 10
Watchdog ................................................................................................................ 10
Serial bus................................................................................................................. 10
PENTA.................................................................................................................... 10
External regulators .....................................................................................................11
Clocks ........................................................................................................................11
Sleep Clock ............................................................................................................. 11
System Clock........................................................................................................... 11
CDMA clock ........................................................................................................... 11
Charging Circuit ........................................................................................................11
CAFE .........................................................................................................................12
Microphones ..............................................................................................................12
Earpiece and XEAR ...................................................................................................12
Clock circuit ...............................................................................................................12
AMPSMOD ...............................................................................................................12
Transmit and Receive RF Signals ..............................................................................12
MAD4 ........................................................................................................................13
DSP ............................................................................................................................13
External Regulator .....................................................................................................13
MCU ..........................................................................................................................13
Memories ...................................................................................................................14
Problems....................................................................................................................... 14
Phone won’t power up ...............................................................................................14
Flash Align .................................................................................................................14
Test 9....................................................................................................................... 14
Test 10..................................................................................................................... 14
In the field ..................................................................................................................14
Battery will not charge ...............................................................................................14
Audio failures ............................................................................................................15
List of Test Points ......................................................................................................16
Test Point Diagrams ..................................................................................................19
RF Troubleshooting ..................................................................................................... 20
WinTesla General Set Up ............................................................................................ 20
Issue 1 04/01 Nokia Mobile Phones Ltd. Page 3
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Disassembly/Troubleshooting Instructions PAMS Technical Documentation
Testing Menu ............................................................................................................... 21
AMPS Fault Finding Setup ........................................................................................21
Cell Band CDMA Fault Finding Setup .....................................................................22
PCS Band CDMA Fault Finding Setup .....................................................................23
Tuning Menu .............................................................................................................23
AMPS Tuning AFC ...................................................................................................24
Description of Test.................................................................................................. 24
Definition of Result................................................................................................. 24
Manual Verification ................................................................................................ 24
Troubleshooting ...................................................................................................... 25
AMPS Tuning Tx Power Levels ................................................................................25
Description of Test.................................................................................................. 25
Definition of Result................................................................................................. 26
Manual Verification ................................................................................................ 26
Troubleshooting ...................................................................................................... 27
AMPS Tuning Tx Modulation Index .........................................................................28
Description of Test.................................................................................................. 28
Definition of Result................................................................................................. 28
Manual Verification ................................................................................................ 29
Troubleshooting ...................................................................................................... 29
AMPS Tuning RSSI ..................................................................................................29
Description of Test.................................................................................................. 29
Definition of Result ...................................................................................................29
Manual Verification ................................................................................................ 30
Troubleshooting ...................................................................................................... 30
AMPS Tuning Rx Audio Gain ..................................................................................32
Description of Test.................................................................................................. 32
Definition of Result................................................................................................. 32
Manual Verification ................................................................................................ 33
Troubleshooting ...................................................................................................... 33
800 CDMA Tuning Tx IF AGC ................................................................................33
Description of Test.................................................................................................. 33
Definition of Result................................................................................................. 33
Manual Verification ................................................................................................ 34
Troubleshooting ...................................................................................................... 34
800 CDMA Tuning LNA Switch ..............................................................................35
Description of Test.................................................................................................. 35
Definition of Result................................................................................................. 36
Manual Verification ................................................................................................ 36
Troubleshooting ...................................................................................................... 36
800 CDMA Tuning Rx IF AGC ................................................................................36
Description of Test.................................................................................................. 36
Definition of Result................................................................................................. 37
Manual Verification ................................................................................................ 37
Troubleshooting ...................................................................................................... 37
800 CDMA Tuning Rx IF Compensation .................................................................38
Description of Test.................................................................................................. 38
Definition of Result................................................................................................. 38
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Manual Verification ................................................................................................ 38
Troubleshooting ...................................................................................................... 38
1900 CDMA Tuning Tx IF AGC ..............................................................................39
Description of Test.................................................................................................. 39
Definition of Result................................................................................................. 39
Manual Verification ................................................................................................ 39
Troubleshooting ...................................................................................................... 39
1900 CDMA Tuning LNA Switch ............................................................................40
Description of Test.................................................................................................. 40
Definition of Result................................................................................................. 40
Manual Verification ................................................................................................ 40
Troubleshooting ...................................................................................................... 41
1900 CDMA Tuning Rx IF AGC ..............................................................................41
Description of Test.................................................................................................. 41
Definition of Result................................................................................................. 41
Manual Verification ................................................................................................ 42
Troubleshooting ...................................................................................................... 42
1900 CDMA Tuning Rx IF Compensation ...............................................................42
Description of Test.................................................................................................. 42
Definition of Result................................................................................................. 42
Manual Verification ................................................................................................ 43
Troubleshooting ...................................................................................................... 43
Test Point Values ......................................................................................................... 44
Issue 1 04/01 Nokia Mobile Phones Ltd. Page 5
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Disassembly/Troubleshooting Instructions PAMS Technical Documentation
NOTE: Do not attempt to remove the antenna from the B–cover.
1.
Remove battery
2.
Remove dust cap by fingernail
3.
Press strongly towards arrow direction
4.
Carefully remove A–cover
Note snap fixings !
5.
Remove back cover
screws (4 pcs)
NOTE! When assembling the B cover screws, use 17 Ncm torque.
Page 6 Nokia Mobile Phones Ltd. Issue 1 04/01
6.
Remove C–cover
NSD-6
7.
Remove UI–module
screws (2 pcs)
8.
Remove UI–module and frame
9.
Remove engine module screw (1 pc)
NOTE! When assem­bling the screw use 17 Ncm torque.
10.
Remove engine module
11.
Remove microphone
Note: When the phone is disassembled (opened), please be careful NOT to TOUCH the antenna clip (x703) or the antenna ground clip (x704). During re-assembly, ensure that the clips are not damaged.
Issue 1 04/01 Nokia Mobile Phones Ltd. Page 7
NSD-6
Disassembly/Troubleshooting Instructions PAMS Technical Documentation

Troubleshooting

Baseband Troubleshooting

Each main portion of the circuit will be described in enough detail for the troubleshooter to determine whether or not that part of the circuit being evaluated is functional. It will be helpful to use the placement diagram, which illustrates all of the necessary testpoints in the baseband circuit, to troubleshoot the phone. The placement diagram is intended to be used concurrently with this document. Herein, TPD refers to Test Point Designation.
TP refers to Test Point originating from schematics. Note that the baseband consists of mainly a few ASICS, and there is very little discrete circuitry other than passive compo­nents. Baseband problems are few compared to previous projects with much more dis­crete circuitry.
Therefore, hardware bugs will not be as obvious since they will likely NOT be a failing part, but perhaps SMD or mechanical issues.

Main Circuit Sections

Power Circuitry

There are two ASICs in the baseband section, which supply power to most of the phone. CCONT is the main power management ASIC, and PENTA is used to supply additional switchable regulators for use in RF. Two discrete linear regulators are used as well.

CCONT

CCONT is the main power management ASIC. Its features include eight 2.8V linear regu­lators, a linear regulator with adjustable output, a reference voltage output, a 5V switch mode regulator, an 8 channel A/D converter, and 32kHz clock circuitry. Each of the main functions and signals is described below, including information on how to verify correct operation.

Vbat

CCONT is powered directly from the battery voltage, Vbat. Since CCONT is a uBGA, the physical connection of CCONTs power pins cannot be verified. Vbat must be checked instead at the closest external component, which is shown as TPD30. Valid voltages are
3.1 – 4.1V and should always be powered, assuming voltage is applied to the battery ter­minals.

Vref

Vref is used as a reference voltage both internal and external to CCONT. It is switchable between the nominal voltages of 1.500V and 1.251V, with the default at power up being
1.500V. The phone uses the 1.251V reference, so once flash software is running Vref must switch to 1.251V.
Check Vref at TPD6. Valid voltages are 1.478 – 1.523V and 1.244 – 1.258V, respectively.
Page 8 Nokia Mobile Phones Ltd. Issue 1 04/01
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Linear Regulators

1. Vbb
Vbb supplies power to most of the baseband circuitry. This regulator should be on at all times during CCONTs power on, reset, and sleep modes. Nominal voltage is 2.8V, but anything in the range 2.7–2.87V is valid. Vbb is found at TPD3.
2. RF Regulators (VR1–VR7)
VR1 through VR7 are referred to as the RF regulators. Most are switchable, and all should be within 2.67 – 2.85V when they are on (2.8V nomi nal). VR1 and VR6 are always on during CCONTs power on mode. The rest of the regulators are switchable and are nor­mally on during one or more of the various phone states, but may be turned on at any time with the service software in order to verify their output. The RF regulators can be checked at the following test points.
a) VR1 – TPD11
b) VR1_SW – TPD12
c) VR2 – TPD40
d) VR3 – TPD38
e) VR4 – TPD4
f) VR5 – TPD39
g) VR6 – TPD10
h) VR7 – TPD41
i) VR7A –TPD9
3. V2V (VMAD)
The V2V regulator is intended to power the MAD4 ASIC core. The output is adjustable from 1.3V to 2.65V in 0.225V steps, and is used with MAD4 ver 3 (but not MAD4 ver 2). The output at V2V, when MAD4 ver 3 is mounted, should be 1.750V ±5% and can be checked on TPD2.

Switch mode regulator

1. V5V (+5V_POWER)
V5V is a 5V switch mode regulator, which always remains on during CCONT power on mode. Valid voltages are 4.8V to 5.2V, and it can be checked at TPD16.
2. VSIM (3V_5V)
VSIM is powered by the same switch mode regulator as V5V, however, it is switchable
Issue 1 04/01 Nokia Mobile Phones Ltd. Page 9
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Disassembly/Troubleshooting Instructions PAMS Technical Documentation
between 3V and 5V. The phone uses VSIM as the 3V FLASH programming voltage, so it should remain off unless the phone is being flashed. Valid voltages are 2.8V to 3.2V, and it can be checked at TPD7 (or TP33 on PWB).
A/D Conversion
CCONT contains a 10–bit A/D converter that is multiplexed between 8 different inputs. They are used mainly for battery and charger monitoring. The 8 inputs are Vbat (battery voltage), ICHAR (charger current), VCHAR (charger voltage), BSI (battery type), BTEMP (battery temperature), VCXOTEMP (PA temperature), RSSI (AMPS receive signal strength), and EAD (accessory detection). These readings can be accessed through the service soft­ware. Check for shorts or opens on the resistor networks connected to these signals if the flash align test software reports that they are out of range.
Watchdog
CCONTs watchdog circuitry consists of an eight bit down counter that causes CCONT to power down when zero is reached. The counter may be reset by loading a new, non–zero value into the watchdog register via CCONTs serial bus. It is difficult to verify the watch­dog function, but the serial bus may be verified.
There is a watchdog disable pin which allows the watchdog timer to expire without shutting down the phone, but this pin is mainly used as one of the methods to turn on CCONT from power off mode. While the phone power key is pressed, this pin should be pulled low and can be checked at TPD 35 (R325).
The watchdog can be disabled by pulling down the above mentioned pin(WDDISX) by installing a 0 Ohm resistor at R307, and removing R325.
Serial bus
Since the serial bus is used to control almost all of CCONTs functions, any shorts or open circuits on these three lines would cause CCONT to be completely nonfunctional. The main symptoms are the following:
CCONT will turn on when the power key is pressed (verify this by checking Vbb), but will then power off after 32 seconds. All three serial bus sig nals (CCONTCSX, UIF_CCONT_SDIO, and UIF_CCONT_SCLK) should toggle when attempting to write to a CCONT register.
Note: If the LCD does not come on during this time, however, it may indicate that the serial bus is functional, but phone does not have valid flash code.
PENTA
PENTA supplies power to the RF section. It has 5 independently switchable regulators that are controlled via separate enable pins. There is also a common enable pin that must be active in order to turn on any of the regulators. Each of the regulators, P1–P5, should have output voltages between 2.7V and 2.85V (2.8V nominal). These can be checked at the following test points.
a) P1 – TPD18
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b) P2 – TPD17
c) P3 – TPD19
d) P4 – TPD21
e) P5 – TPD22

External regulators

There are three regulators used in addition to CCONT and PENTA. One is controlled by CCONTs VR7 regulator output and used as a low noise power source for RF. This regulator is 2.8V nominal and can be checked at TPD9.
The second regulator is used to power the data cable accessory, so output is enabled only when a data cable accessory is detected. This regulator is also 2.8V nominal and can be checked at TPD51 (shares SGND).
The third regulator is used to power the DSP portion of MAD4. It is enabled by Vbb, and difference between the rise times of the DSP regulator and Vbb should be less than 200usec. This regulator is 2.8V nominal and can be checked on pin 1, 30, or 115 of the MAD4 ASIC. (This component is most likely stuffed if MAD4_V3 is used.)

Clocks

Sleep Clock
The 32kHz sleep clock is generated by CCONT, and can be checked at TPD31. The 32kHz square wave will be present only after the phone is turned on. If no signal is present on this line, check the output of the oscillator at R304. This signal should be a 2Vpp clipped signal riding on 1.5V DC.
System Clock
The 19.2MHz system clock is generated by the VCTXO in the RF section, and then squared in CAFE. Check TPD23, which should be approximately a 0.5V sinewave riding on 1.8V DC. Check TPD25 (or TP14*), which should be a 2.8V squarewave. This clock is not active during the phone’s sleep mode (CLK_EN is low during sleep mode).
*Note that TP14 on NSD–3AW has been moved.
CDMA clock
The CDMA clock is 9.8MHz and is generated in CAFE with a PLL. This should be a 2.8V square wave and can be verified at TPD24 (TP13).

Charging Circuit

The charging switch, CHAPS, is controlled by a PWM from CCCONT. This PWM can be at 1Hz or at 32Hz, with varying duty cycles, and should only be active when a charger is detected. The frequency should be 1Hz when an ACP–7 is detected and 32Hz when an ACP–9 is detected. To verify correct operation of CHAPS, monitor the charging current
Issue 1 04/01 Nokia Mobile Phones Ltd. Page 11
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Disassembly/Troubleshooting Instructions PAMS Technical Documentation
(ICHAR) with the service software. When the PWM is off, current must be approxi­mately 200uA. When the PWM is on, it must be greater than approximately 300mA.

CAFE

The CAFE ASIC performs various functions with respect to the RF circuitry and audio. It digitizes the analog voice signals from the microphone as well as converts received digi­tal data to voice signals to be sent to the earpiece. This also includes accessory micro­phones and speakers. It also generates and decodes I and Q data for CDMA, and demodulates FM (AMPS) signals. CAFE also acts as a clock squaring circuit and CDMA clock generator.

Microphones

The internal microphone is biased using transistor V201, which is powered by VR1_SW (TPD12, 2.75VDC). Check also the output of V201. V201, R220 and C212 should be installed, and R202 should not be installed. MICP must be about 1.7VDC, and MICN must be about 0.4VDC. Internal microphone bias is active only during a call. The XMIC is biased by the AUXOUT signal (pin 75) through R209 and R208. The output voltage at pin 75 is about 1.5V.

Earpiece and XEAR

The internal earpiece is driven differentially from pins 77 and 80 (EARP and EARN). The DC voltage on these two pins is 1.35V. The difference in the DC voltage between these two pins must not be more than 50mV.
The XEAR signal drives audio to the external accessories. The CAFE signal name is HF (pin
81). The DC level on this pin should be 1.35V. HFCM (pin 82) should also be at 1.35V. The difference in DC voltage between these two pins should not be more than 50mV.
Note that SGND is the return path for XMIC and XEAR.

Clock circuit

A 19.2MHz sinusoid should appear on pin 25 (Also TPD23). This is from the VCTCXO in the RF. The CAFE will then produce a 19.2MHz clock at pin 18 (TPD25), and a 9.83MHz clock on pin 19 (TPD24). See also Clocks section.

AMPSMOD

AMPSMOD is the voice signal to modulate (FM) the RF carrier for transmission. It is the voice signal that has been processed by the DSP(MAD4) for transmission in AMPS mode. It represents a modified version of the signal produced by the microphone (CAFÉ pin 58).

Transmit and Receive RF Signals

In CDMA mode, receive I and Q channel RF signals [RXIQ(3:0)] come into CAFÉ at pins 44, 45, 47, and 48. C207, C208, C209, and C210 can also be checked for these signals since they are in series with the CAFÉ pins. Transmit I and Q RF signals [TXIQ(3:0)] can be seen at pins 55, 56, 59, and 60 and C201, C204, C222, and C224.
Page 12 Nokia Mobile Phones Ltd. Issue 1 04/01
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In AMPS mode, the modulated receive RF signals (LIM_P and LIM_N) can be seen coming into pins 23 and 24 and C216 and C217. For the AMPS Transmit signal, see AMPSMOD above.
Both the TX and RX paths are also described in section Audio Failures.

MAD4

The MAD4 ASIC is the core of the baseband functionality and basically contains the DSP, MCU, and CDMA logic. The DSP is used to perform functions such as RF control, DTMF tone generation, and it implements the vocoder. The MCU is used to perform functions that do not require as much power. These are higher level functions such as UI software (key presses, backlighting, LCD functions, etc.) and mode control.
DSP
The DSP sends control signals to the RF via PDMs. In order to control RF parameters such as TX_VCO_CAL or TX_LIM_ADJUST, a continuously variable analog signal must be used. Since the DSP outputs only digital signals, a PDM RC circuit is used to convert the digital output signal to an average analog voltage. A PDM line will always have a series resistor followed by a shunt capacitor. The output of the MAD4 PDM lines will appear as square­wave signals. However, after the shunt capacitor the signals will appear to be DC with perhaps a slight ripple. The RC circuit acts as an integrator in order to yield the average value (DC) of the squarewave signal.
The transmit data bus (TXD(7:0)) is 8 bits wide. In CDMA this bus is multiplexed between sending I and Q data. The signals required to transfer TX data are TXGATE, CLK9M80, and IQSEL. TXGATE must be high to transfer data, and the data is clocked by CLK9M80, which is running at 9.8MHz. In AMPS mode, CLK9M80 is running at 120kHz, therefore, data is being transferred from MAD4 to CAFE at 120kHz.
The JTAG lines are intended to be used to operate the DSP (and/or MCU) externally.

External Regulator

A separate 2.8V external regulator powers the Lead (DSP) independently. Eventually, the next version of MAD4 will be used and the Lead may be powered by VMAD from CCONT. See External Regulators section under CCONT/Linear Regulators. Note: This regulator is also mentioned in section Power Circuitry.
Note: this regulator may not be present on any HW that uses MAD4_V3.
MCU
The MCU is used to perform functions that require less processing power than the DSP. It runs UI software, mode control, interfaces to MBUS, downloads code to flash, reads and writes the EEPROM, controls charging, and interprets A/D data from CCONT. (Used only in NSD–3AW [and NDS–1AW] NBA chip is used in synchronization between MAD4 and SRAM.)
Issue 1 04/01 Nokia Mobile Phones Ltd. Page 13
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Disassembly/Troubleshooting Instructions PAMS Technical Documentation

Memories

MAD4 interfaces to three memories — Flash, SRAM, and EEPROM. All of them are pow­ered by 2.8V (Vbb). During Flash programming, Vpp (signal name is Vff on schematic) is driven with 3V at the PC flash stations.

Problems

Phone won’t power up

Do a visual inspection. Verify that all parts are on the board correctly, and that none is missing.
Check that the 32kHz clock turns on when attempting to power up.
Check the power circuitry. This includes VBAT, Vref, and all of the linear regulators, as well as the Penta regulators. Verify also that the external regulator that powers MAD4 (LEADVCC) is functional – if present.

Flash Align

Test 9
High current: This indicates that the problem is likely caused by a shorted component. Check orientation of major components (including RF), and check for shorts. Likely com­ponents are those that are powered directly from Vbat such as CCONT, the PAs, and vari­ous capacitors.
Low current: This indicates that CCONT is not powering on. Verify CCONT circuitry.
Test 10
Flash: Failure to flash is the main baseband failure. Check all the CCONT regulators, especially Vbb, VR1, and VR6 for shorts. Check clocks and reset circuitry. Check for shorts on the address, data, and chip enable lines on the memories and MAD4. If a short is detected, it may be that it is beneath the BGA flash and may have to be replaced.
NOTE: There is no ROM software that can be run when the phone does not flash. There­fore, it must be visually (or by Ohmmeter) determined whether there is an eventual short between two or more of the address or data lines.

In the field

Cracked or broken solder may cause failures to occur. Reflowing some of the major com­ponents may fix problems in case the phone is functioning errantly (some buttons may not work, the phone may not ring, etc.) or may not power on anymore.

Battery will not charge

If the battery won’t charge (phone won’t allow the battery to charge), check CHAPS and the charging circuit. It may also be necessary to verify the A/D functionality of CCONT since this is the method of detecting battery type, charger type, etc.
Page 14 Nokia Mobile Phones Ltd. Issue 1 04/01
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