1 INTRODUCTION OF DS210 ......................................................................................................................................................................................................3
1.1 ID .......................................................................................................................................................................................................................................3
1.2 MAIN TECHNICAL SPECIFICATION .....................................................................................................................................................................................4
1.3 RF CHARACTERISTICS ........................................................................................................................................................................................................4
2PCBA OVERVIEW .......................................................................................................................................................................................................................4
3EXPLANATION OF SCHEMATIC.............................................................................................................................................................................................8
3.1 SYSTEM FUNCTIONAL DIAGRAM ...........................................................................................................................................................................................8
3.2 PRINCIPLE OF RF CIRCUIT...............................................................................................................................................................................................8
3.2.1 Main function of RF .......................................................................................................................................................................................8
3.2.2 Receiver..................................................................................................................................................................................................................9
3.2.3 Transmitter.........................................................................................................................................................................................................10
3.2.4 Frequency Synthesizer.................................................................................................................................................................................10
3.2.5 Digital Calibration Loop .........................................................................................................................................................................11
3.2.6 Fast Acquisition System............................................................................................................................................................................11
3.2.7 Voltage Control Crystal Oscillator .................................................................................................................................................11
3.2.8 Regulator .............................................................................................................................................................................................................11
3.3 PRINCIPLE OF BASEBAND CIRCUIT ..................................................................................................................................................................................12
3.3.1 Baseband chip—MT6325 ...................................................................................................................................................................................12
3.3.2 Explanation of power management unit in MT6235.....................................................................................................................12
3.3.2.1 10 channel power supply......................................................................................................................................................................13
3.3.2.2 Power on circuit ......................................................................................................................................................................................13
3.3.2.3 Charge Circuit ...........................................................................................................................................................................................14
3.3.3 SIM interface....................................................................................................................................................................................................15
3.3.4 Principle of audio frequency circuit.............................................................................................................................................15
3.3.5 LCD circuit.........................................................................................................................................................................................................16
3.3.6 Camera circuit .................................................................................................................................................................................................17
3.3.7 Bluetooth circuit ..........................................................................................................................................................................................17
3.3.8 T-flash card circuit ...................................................................................................................................................................................18
3.3.9 System interface.............................................................................................................................................................................................18
3.3.10 FM circuit........................................................................................................................................................................................................19
3.3.11 Key interface ................................................................................................................................................................................................20
4MAIN SPARE PARTS INTRODUCTION...............................................................................................................................................................................20
5FAILURE ANALYSIS..............................................................................................................................................................................................................21
5.1 LEVEL 1PRIMARY REPAIR ..............................................................................................................................................................................................21
5.1.1 Upgrade software.............................................................................................................................................................................................21
5.1.1.1 Install USB cable driver ...................................................................................................................................................................21
5.1.1.2 Upgrade software ......................................................................................................................................................................................21
5.1.1.3 Upgrade fail halfway.............................................................................................................................................................................24
5.1.2 Replace packages.............................................................................................................................................................................................25
5.1.3 The guidance for user to use some functions............................................................................................................................25
5.2 LEVEL 2INTERMEDIATE REPAIR .....................................................................................................................................................................................25
5.2.1 Cover Broken ......................................................................................................................................................................................................26
5.2.2 Replace Keypad (Structure Parts) ......................................................................................................................................................26
5.2.3 LCD Broken ...........................................................................................................................................................................................................26
5.2.4 Microphone Broken ..........................................................................................................................................................................................26
5.2.5 Receiver Broken ...............................................................................................................................................................................................26
5.2.6 Speaker Broken .................................................................................................................................................................................................26
5.2.7 Camera Broken....................................................................................................................................................................................................26
5.2.8 Receiver FPC Broken .....................................................................................................................................................................................26
5.2.9 Slide FPC Broken.............................................................................................................................................................................................26
5.2.10 LCD PCB Broken..............................................................................................................................................................................................27
5.2.11 Mainboard PCB Broken................................................................................................................................................................................27
5.3 LEVEL 3SENIOR REPAIR ................................................................................................................................................................................................27
5.3.1 Power on and initial problem................................................................................................................................................................28
5.3.2 Upgrade Problem ...............................................................................................................................................................................................29
5.3.3 Power charge problem: Charger .............................................................................................................................................................30
5.3.4 Power Charge Problem: USB .......................................................................................................................................................................31
5.3.5 RF Signal Weakness Problem (Have no signal even)................................................................................................................32
5.3.6 LCD Display Problem .....................................................................................................................................................................................33
5.3.7 LCD Backlight Problem.................................................................................................................................................................................34
5.3.8 Camera Problem .................................................................................................................................................................................................35
5.3.9 SIM I Card Problem(Phone can’t access SIM card) ..................................................................................................................36
5.3.10 T-card Problem(Phone can’t access T-flash card)...............................................................................................................37
5.3.11 Receiver Problem(Unable to hear any voice from each other during the call)..............................................38
5.3.12 Speaker Problem(Unable to hear any voice when playing MP3) ....................................................................................39
5.3.13 Microphone Problem: Internal(Microphone doesn’t work) ................................................................................................40
5.3.14 Microphone Problem: External(Earphone MIC doesn’t work)............................................................................................41
5.3.15 Earphone Problem(Unable to detect earphone insert)........................................................................................................42
