C8813 Service Manual
V1.0
Directory
Chapter 1 : Introduction
1.1 Appearance
1.2 Product Features
Chapter 2 : Repair information described in Guidelines
2.1 Documentation Instructions
2.2 Maintenance Considerations
2.3 Maintenance guidelines for access to information
Chapter 3 hosts exploded diagram
Chapter 4 motherboard components location map
Chapter 5 Software Upgrade
5.1 before upgrading to prepare
5.2 Upgrading the hardware connection
5.3 USB driver installation
5.3.1 upgrade process
5.3.2 Forced Upgrade
5.4 SD upgrade
5.4.1 SD card normal upgrade
5.4.2 SD card is mandatory upgrade
5.5 Exception Handling
Chapter 6: Repair Tools
Chapter 7: Figure disassemble step
Chapter 8: Installation steps Figure
Chapter 9: Mobile principle and failure analysis
9.1 Block diagram and introduce mobile phone
9.2 baseband unit
9.2. A power management circuit switched
9.2.2 charge management circuit
9.2.3 clock circuit
9.2.4 Flash circuit
9.3 GSM radio unit
9.3.1 CDMA RF transceiver circuit
9.3.2 GSM RF transceiver circuit
9.4 peripheral circuits
9.4.1 Display
9.4.2 Vibration
9.4.3 Receiver and SPK
9.4.4 microphone
9.4.5 headphones
9.4.6 SIM card
9.4.7 IO Interface
9.4.8 SD Card Interface
9.4.9 FM + BT
Chapter 10 :of the PCB and BGA chip solder indication map
Chapter 11: Functional Test
11.1 Keyboard and Features
11.2 MMI test
11.3 Voice Test
Chapter 9 Mobile principle and failure analysis 9.1 Block diagram and introduce mobile phone
C8813 is a Qualcomm MSM8625-based independent research and development of CDMA candy bar
phone, the use of QUALCOMM Incorporated MSM8625 PM8029 ch Board includes MSM8625,
PM8029, RF devices, connected by FPC LCD, Receiver, Speaker by shrapnel and
Motherboard connector, MIC connected to the board by soldering, welding motor SIM card / SD
card soft board, through the connector to the motherboard with
Even. RF antenna connected by shrapnel, with shell structure, batteries, constitutes a whole. In
addition to providing basic voice, Short message function, also supports phone book and SMS saved
in the UIM card and mobile phone two storage modes, support MicroSD card storage. Hardware
The support FM radio and recording function.
C8813 supports color TFT LCD, dot number is 854 × 480; provide external Micro USB type charger
interface, UIM cards
Interface, support for polyphonic ringtones and vibration function, FM function. RF antenna built-in,
optional 1700mAh lithium battery, CDMA standby Time of 400hrs around (with the actual network
related), continuous talk time of about 11 hrs (with the actual network related).
9.2 baseband unit
9.2.1 Boot power management circuits
Circuit diagram:
KPD PWR ON
C8813 Maintenance Manual V1.0
Circuit theory analysis:
C8813 uses separate power management chip PM8029, the principle of all by the power of
Qualcomm code control, power on the map by the principle
KPD_PWR_ON detection voltage is active low. The power mains voltage in the VHP_PWR process by
PM8029 power management chip transfer Change the table below to get a variety of voltage:
Failure analysis process: Can not boot into boot no fault current, low current, high current and other
categories, many machines are due to power anomalies caused, When faced with a similar power
failure, please troubleshoot problems caused by power supply circuit in accordance with
troubleshooting methods.
1 boot no current: DC power boot, press the power button, display the current DC power from 0 to
5mA;
2 Boot Little Current: DC power boot, press the power button, the DC power display current 5mA to
100mA;
3 large boot current: DC power boot, press the power button, the display current 300mA DC power
over;
When the situation C8813 phone can not boot, can fail to judge by observing DC power supply
current.
1. No current
Does not boot
External fake batteries and electrical repairs
Source, press the power button, observe the power
Flow
No current
Whether the keys copper oxide? Y Clean button
N
Measure VPH_PWR
Voltage is normal 3.4 to 4.2 =
Maintenance of power supply voltage N Inspection U201
Y
Check whether the clock is normal? N Check the clock
X301 U3101
Y
Depot Repair
2.A small current
Does not boot
External fake batteries and electrical repairs
Source, press the power button, observe the power
Flow
A small current
Detect PM The output voltage is N Inspection U201
No normal?
Y
Measure X301
The output frequency is = 32.768KHz N Re-welding or
Or replacement X301
U3101 Export 19.2MHz U3101
Y
Depot Repair
3.A large current
Does not boot
External fake batteries and electrical repairs
Source, press the power button, observe the power
Flow
A Large current
Detection J1611 3 Pin Y Detection U201 and
Grounded? J1611
N
U201 detection voltage is normal? N Re-welding
or replace U201
Y
Depot Repair
9.2.2 charge management circuit
Circuit diagram:
circuit theory analysis:
C8813 uses PM8029 power management chip, the internal integration of the charging scheme, there
are three charging status: red trickle power, constant Current charging and constant voltage
charging. Have adopted the same charge path: USB_VCHG → VCHG → VPH_PWR → Q201, pin3 →
VBAT Using FAN5402UCX dedicated power chip 1A charging, using I2C communication and control,
two interfaces GPIO13 (I2C_SCL_DCDC), GPIO98 (I2C_SDA_DCDC). This charge management chip
straight from VCHAG USB interface.Then take power from the I2C control. Output VPH_PWR is
powered PM, while charging the battery.
The functional block diagram as follows:
4-16 charging chip functional block diagram
Charging flow diagram as follows:
Charging flow diagram in Figure 4-17
This chip has three modes: charge mode, boost mode and high-impedance mode. Normal start
charging mode charging process, boost Mode is USB-OTG mode, high-impedance mode is not
charging power saving mode (standby).
When the external power supply (charger or USB) connection to the phone, to determine the
external voltage is greater than VuvloPM, then look VAUXPWR <VLOWV (specific meaning to the
battery voltage is less than the maximum battery voltage). If the battery voltage is maximum, no
charge Electricity; Instead, start the charging process.
Several voltage and current explanation:
V (SHORT) trickle charging, constant current charge starting voltage
V (OREG), constant current charging, constant voltage charging start voltage
IO (CHARGE) constant charging current
I (IN_LIMIT) constant charging current limit, and IO (CHARGE) 2-to-1
I (SHORT) trickle charge current
V (RCH) As the rechargeable battery voltage
By monitoring the cell phone chip CSOUT pin mains voltage, when the battery voltage is less than V
(SHORT), start the trickle charge; When electricity Battery voltage is greater than V (SHORT) is less
than V (OREG) constant current charging starts; When the battery voltage is approximately equal to
V (OREG), constant voltage charging start Electricity; When the charge current is less than a certain
value while the voltage exceeds a certain range V (RCH), stop charging. Chip built-in 15 minutes and
32 seconds timer, saving CPU resources, automatically starts 15 minutes timer that no i2c control,
parameter use to load their own charge. If the CPU via I2C control, then starts a 32 second timer.
Process is as follows:
BQ24152 timer flowchart in Figure 4-18 under charging mode
Actual circuit hardware OTG man received a level greater than 1.4V, the initial charging charging
port is limited to the maximum current the whole 500mA, the charging process to be detected after
a specific software to disable this limit. FAN5402UCX has its own temperature detection function
Able, when the temperature reaches the upper limit TJ TCF, reducing the charge current, stop
charging when when TJ is less than the upper temperature limit TCF10 degrees, heavy New start
charging. When the charging voltage VBUS charge voltage is less than the sleep (VAUXPWR + Vslp)
when, FAN5402UCX into sleep mode to save power. FAN5402UCX can continue charging voltage
detection VBUS, VIN (min) when VBUS is less than the set threshold, Re-determine the phone stops
charging and wait for a TINT. FAN5402UCX with charging overvoltage protection, battery over-
voltage protection Function, battery reign detection, no battery start.
Failure analysis process:
Symptom: The phone is not charging failure is usually the case, there are two: First, after the charger
is connected to the phone, the phone did not respond; Another phone while charging is displayed,
but can not charge the battery. For no charge fault plane, first detected I / O interfaces, Look for any
obvious damage. After the charger is connected to the phone, the phone without charging indicator
After the charger is connected to the phone, the phone has a charging indicator, but you can not
charge the battery
Into the charger is not charging
Charger is working properly? N Replacement charger
Y
Observation USB connector Y J901 welding
J901 whether Weld?
Are there voltage measurement N C231? N Check fuses F901 and
beads LB901
Y
Check whether the charging chip U901 N Replacing U901
Output voltage VPH_PWR
Y
Check whether the output pin 3 Q201? N Replacing Q201
Y
Battery connector J902 is damaged? Y Replace the battery
connector J902
N
If the battery is damaged? Y Change Battery
N
End
This section schematics signal summary:
Signal Name Function Details Test Reference value or waveform chart
USB_VCHG Charger power input.
VCHG External USB powered 0—5 V
charging chip input.
I2C_SCL_DCDC Charge control signal chip. No
I2C_SDA_DCDC Charge control signal chip. No
VPH_PWR The main power supply to the power Supply voltage
supply module here variation range
0-4.2V
BAT_FET_N MOS transistor battery (Q201)
of the control output.
VBAT Battery voltage Battery voltage
variation range
0-4.2V
USB_HS_DP USB differential data positive input No
USB_HS_DN USB differential data positive input. No
9.2.3 clock circuit
Circuit diagram:
19.2MHz
Circuit theory analysis:
As Figure: 19.2MHz clock output access PM8029 and RTR6285A, TPK_LO_ADJ control precision clock
output. TPK_LO_ADJ has two filter circuit, R204, C232 and R3101, C3101. After PM output to the
host system as the main chip Clock.
32.768kHz crystal oscillator input to the PM8029, the PM output to the system
Failure analysis process:
Symptom: The phone does not boot, or easy to crash, check 32.768kHz crystal oscillator X301
detection and U3101 have not A signal, or the frequency is stable.
Solution: Replace the X301 or U3101, to see whether it is normal, otherwise replace the PM8029.
This section schematics signal summary:
Signal Name Function Details Test Reference value or waveform chart
XTAL32K _OUT 32.768kHz master clock
signal output terminal
XTAL32K_IN 32.768kHz master clock
signal input terminal
VREG_TCXO 19.2MHz crystal power 2.85V
TRK_LO_ADJ 19.2MHz frequency control NO
signal output
RTR6285_TCXO 19.2MHz clock output
TCXO 19.2MHz clock output
9.2.4 Flash circuit
Circuit diagram:
Circuit theory analysis:
MSM8625 can be accessed through the high-speed bus EBI1 connected thereto by LPDDR PoP
(Package-on-package), At the same time, but also the low-speed access to external memory bus EBI2
eMMC by one, as shown below:
Figure 4-2 C8813 Mobile Memory Interface Analysis
EMMC uses eight data lines for transmission, C8813 products using the 4G EMMC devices.
Failure analysis process:
Symptom: The phone does not boot or boot currents can rise to tens of mA, Processing methods:
Upgrade or loading software, testing VREG_DCDC_2P85 voltage is normal, if normal peripheral
devices, whether Replace the U1800.
This section schematics signal summary:
Signal Name Function Details Test Reference value or waveform
Map
SDC3_DATA3 Data line
SDC3_DATA2 Data line SDC3_DATA1 Data line SDC3_DATA0 Data line SDC3_DATA7 Data line SDC3_DATA6 Data line SDC3_DATA5 Data line SDC3_DATA4 Data line
SDC3_CLK Clock
SDC3_CMD Command
VREG_DCDC_2P85 Flash Power 2.85V
VREG_S3 Power supply 1.8V
MSM_RESOUT_N Reset VPH_PWR System power, 2.85V DCDC
chip power supply 9.3 GSM radio unit
The band CDMA GSM switch gating circuit schematics
Switch Select Truth Table
Behind the main antenna RF switch model is 47140032, which control logic list is as follows:
Select the
band
ANT_SEL0 (GPIO75) ANT_SEL1 (GPIO74)
ANT_SEL2 (GPIO73)
ANT_SEL3 (GPIO72)
CDMA CELL TX/RX 0 0 1 0 GSM 900 TX 0 0 0 1 GSM 900 RX 1 x 1 1 GSM 1800 TX 0 0 1 1 GSM 1800 RX 1 x 1 0
GSM 1900 TX 0 0 1 1 GSM 1900 RX 1 x 1 0
Description: on the table "L" voltage range is 0 ~ 0.2V, "H" voltage range 1.8 ~ 3.0V. "X" indicates not
involved. These control signals given by the MSM8625.
9.3.1 CDMA RF transceiver circuit
TX CELL DUPLEXER & PA
CDMA RF Transceiver
9.3.2 GSM RF transceiver circuit
GSM PA inheritance RF selector switch inside.
After RTR6285A using GSM RF transceiver chip.
9.4 peripheral circuits
9.4.1 Display
circuit diagram:
Circuit theory analysis:
C8813 is optional LCD TFT 4.5 inches, dot number 854 × 480, using the MIPI interface.
C8813 LCD interface products using MIPI, just using two pairs of differential signal lines, a pair of
power lines, support 60Hz refresh rate. With frame synchronization, use GPIO_097 of MDP_VSYNC
synchronization signals as data transmission, to avoid split-screen phenomenon.
Failure analysis process:
Symptom: You can boot but no display LCD
Solution: Check the LCD
No LCD display
Reload software
No normal? Y End
N
Whether the backlight? N Check the L1303, U1303
Y
U1601 whether N Re-welded
Welding good?
Y
Check the connectors N Rest J1302
J1302 whether welding
Good contact?
Y
Depot Repair
(No LCD display repair process)
This section schematics signal summary:
Signal Name Function Details test reference value or waveform chart
VREG_L12_2P85 LCD analog voltage, 2.85
VREG_S3 I / O port digital voltage 1.8
MIPI_DSI_LANE2_P differential signal + 1.8
MIPI_DSI_LANE2_N differential signal - 1.8
MIPI_DSI_LANE1_P differential signal + 1.8
MIPI_DSI_LANE1_P differential signal - 1.8
LCD_RST LCD power-on reset signal is 1.8
1.8 MDP_VSYNC_P longitudinal frame synchronization signal
LCD_ID0 vendor ID information 1.8
LCD_ID1 vendor ID information 1.8
MIPI_DSI_CLK_P clock differential signal + 1.8
MIPI_DSI_CLK_N differential clock signals - 1.8
9.4.2 Vibration
circuit diagram:
Circuit theory analysis:
PM8029 pin VIB_DRV_N as a drive pin vibrator motor is placed on the motherboard. When the
motor of appetite, VPH_PWR and VIB_DRV_N are high.
failure analysis process:
Symptom: Motor appetite
Treatment:
No vibration motor
Reload software Y End After normal?
N
Check whether the motor Weld? Y After verification welding
ends N
Measure whether motor-powered Normal? N Vibration test negative
Whether extremely low?
Y
Check the power Replace the motor if Y End
Normal?
N
Depot Repair (No vibration repair process)
This section schematics signal summary:
Signal Name Function Details test reference value or waveform chart
VPH_PWR main power supply
to the motor where no
VIB_DRV_N foot motor drive signal,
then no motor negative
9.4.3 Receiver and SPK
SPK¬ circuit diagram:
C8813 offers three audio outputs:
1. Receiver output. The output signal from the CPU.
2. Speaker output. After the PM8029 amplifier output to Speaker.
3 headphone output, C8813 dual channel headphone design.
Signal Name Function Details test reference value or waveform chart
EAR1_AMP_1_OP output to the receiver without
EAR1_AMP_1_ON output to the receiver without
SPK_OUT_L_P after PM8029 amplifier output to the SPEAKER None SPK_OUT_L_M after PM8029 amplifier output to the SPEAKER None
Failure analysis process:
Symptom: After creating a call by saying no.
Treatment:
After the call is established, then no subject
Reload software
After normal? Y End
N
Check the earpiece volume settings
Set normal? N Adjust the
volume
to see if normal
Y
View receiver even N Re-welded connections
Line is normal?
Y
Are misjudgment
headphones Insert? Y Overhaul
headphone connector
N
Replace the receiver is
No normal? Y END
N
Check the U201 peripheral level
Are Weld Road deviation? Y END
N
Depot Repair
9.4.4 microphone
circuit diagram:
Master Mike:
Circuit theory analysis:
C8813 board has only one microphone, using HSED_MICBIAS (Headphone MIC PM8029
HSED_BIAS1),, MSM_MICBIAS (MIC 7227A MIC_BIAS) power supply. Failure analysis process:
Symptom: No transmitter failure
Treatment:
After the call is established, no microphone
Reload software
After normal? Y END
N
Re-welding MIC
To see whether it is normal? Y END
N
Check the electrical MICBIAS N Check the
Whether the pressure is normal? C507
Y
Replace the MIC whether
Normal? Y END
N
Depot Repair
This section schematics signal summary:
Signal Name Function Details test reference value or waveform chart
MIC1_P main mic input without
MIC1_N main mic input without
MSM_MICBIAS Master Mike bias voltage without
9.4.5 headphones
circuit diagram:
Circuit theory analysis:
Headphones into the detection by HS_DETECT_N (GPIO_086) pin judgment:
When headphones are plugged in before, HS_DETECT_N is pulled into a high level VREG_S3;
When the headphones are plugged in, HS_DETECT_N is pulled low, a low level.
Headphone MIC power supply uses MIC_BIAS1 (PM8029 / HSED_BIAS1) power, and used the
headset to answer detection.
Failure analysis process:
Symptom: No sound headphones
Treatment: Replace the headset, replace the headphone jack.
After the establishment of the call, the headset
Hear the sound of the call
Check the earpiece volume settings
Set normal? N Re-set the volume
Y
Replacing normal headphones
Normal? Y End
N
Plug in your headphones
HS_DETECT whether
Voltage change? N Replace the headset seat
Y
Depot Repair
This section schematics signal summary:
Signal Name Function Details test reference value or waveform chart
FM_ANT FM antenna without
HPH_OUT_L stereo headphone output without
HPH_OUT_R stereo headphone output without
HSED_MICBIAS headset MIC bias voltage signal
MIC2_P headphones without MIC input
MIC2_N headphones without MIC input
HSED_ADC_DET headset MIC detect voltage changes
HS_DETECT headphones into the detection voltage change
GND_MIC3 headset MIC to no
9.4.6 SIM card
circuit diagram:
Circuit theory analysis:
C8813 SIM card on the soft board, connected through the motherboard connector interface
provides signal input and output is controlled by the PM8029.
failure analysis process:
Symptom: UIM card is not recognized
Solution: First check the UIM deck is normal,
Do not read the UIM card
Replace the UIM card Y end
After normal?
N
Check the UIM card N Welding or replacement
UIM card Block is normal?
Y
Check VDD_SIM? N Check VDD_SIM
Normal?
Y
Deboot repare
This section schematics signal summary:
After level conversion by PM8029 for the MPP pins to communicate with the SIM card.
VREG_L16_UIM1 voltage can be set to 1.5 ~ 3.05V. USIM interface general operating level of 1.8V or
3.0V. The following table
USIM level for the PM8029's conversion interface:
MSM and the interface signals Level USIM card and interface signals level
UIM1_RESET VREG_L16_UIM1 UIM1_MSM_CLK VREG_S3 UIM1_CLK configured by s.ware UIM1_MSM_DATA UIM1_DATA
Note: Due to the number of user actions SIM card number, so the increase TVS tube, providing static
and surge protection.
9.4.7 IO Interface
circuit diagram:
Circuit theory analysis:
IO interface to connect the charger when the charger provided VCHG charging voltage for battery
charging; When connecting cable,
USB_HS_DN and USB_HS_DP phone for communications and computer (for software upgrades, read
the phone information, etc.).
Failure analysis process:
Symptom: not charging, I / O interfaces nowhere
Treatment: Clean, plus welding or replacement interfaces
This section schematics signal summary:
Signal Name Function Details test reference value or waveform chart
VCHG charging high power input, 5V
USB_DM digital signal without
USB_DP digital signal without
9.4.8 SD Card Interface
Circuit diagram:
Circuit theory analysis:
Plus U1402 for ESD and EMI filtering.
Failure analysis process:
Symptom: does not know the card, no card reader
Treatment:
Do not read Micro-SD card
After replacing the card is Y Do not read Micro-
Normal? SD card
N
U1402 both sides of the signal N Re-welding U1402
Are conduction?
Y
Update software verification is Y END
No normal?
N
Deboot repare
9.4.9 FM + BT
circuit diagram:
BT FM Principle Analysis:
C8813's design, using BT, FM combo modules to achieve its function, using Qualcomm's WCN2243
achieved.
In this design as a separate BT antenna, FM antenna to the headphone left and right channels.
MSM8625 provides PCM and UART interfaces directly connected with the PCM, UART signal BT
module interface signals given
Defined as follows:
MSM8625A signal line definitions
GPIO_44 UART1_CTS_N sent to the slave master's ready to receive
GPIO_43 UART1_RFR_N from the machine to the host issued clear to
send
GPIO_46 UART1_TX send signals
GPIO_45 UART1_RX received signal
GPIO_69 AUX_PCM_DIN PCM input
GPIO_68 AUX_PCM_DOUT PCM output
GPIO_70 AUX_PCM_SYNC PCM synchronization
GPIO_71 AUX_PCM_CLK PCM clock
GPIO_107 MSM_WAKES_BT wake up the host
GPIO_83 BT_WAKES_MSM ake BT
PM8029 provides audio input interface, directly connected with the left and right channel signals FM
module interface signals are defined as follows:
WCN2243 network MSM8625 Description
FM_RXP FM_ANT FM antenna (headset)
FM_RXN ------
FM_VDD2P5 SR_AVDD2P5
FM_AOUT1 FM_OUT_L PM8029 LINE_IN_LP FM OUTPUT
FM_AOUT2 FM_OUT_R LINE_IN_RM FM OUTPUT
PM8029
Failure analysis process:
Symptom: FM does not work
Treatment: If you can find a signal, but no sound, check the headset
pathway.
No Signal FM
FM silent
FM station search result is not satisfactory
After replacing the normal headphones
Normal? Y end
N
Check the seat re-welding headphones
After normal? Y end
N
After updating the software is
Normal? Y end
N
Deboot repare
Chapter 10 of the PCB and BGA chip solder indication map
Red (R: 255, G: 0, B: 0): Empty Point
Green (R: 0, G: 255, B: 0): ground
Blue (R: 0, G: 0, B: 255): solder
TOP:
BOTTOM:
U201:
U401:
U1800
U3901:
U901:
U1402:
U6301:
U6100:
U6000:
U1205:
U1002:
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