Mic ETS2228 Page 42 Maintenance Manual Download

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ETS2228 Maintenance Manual

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12070006

TCXO,19.2MHz,2.8V,2.5ppm,-30degC,85degC

X501

12020102

TCXO -32.768KHZ

X601

39080088

Operation Amplifier,Headphone Audio Power Amplifier with Digital

Volume Control,2.0V~5.5V,1MHz,Stereo,LLP,Terminal Dedicated

U602

7.2 Schematic Circuit Diagram

7.3 Mainboard Structure Diagram

Please refer enclosed pages for BOM Schematics & Silk Screen.

7.4 Test Point Location Diagram

Summary of Contents for ETS2228

Page 2: ... 6 Chapter 3 Detailed Introduction of Functional Module 15 3 1 Power Part including power supply and power management 15 3 2 Base Band Part 20 3 3 Power Management Part 20 3 4 RF Part 23 Chapter4 Engineering Mode and Test Mode 29 4 1 Entrance to engineering mode and test mode 29 Chapter 5 Troubleshooting 30 Chapter 6 Nam Programming 40 Chapter 7 Appendix 41 7 1 Damageable Spare Part List 41 7 2 Sc...

Page 3: ... ETS2228 Fixed Wireless Terminal has the following features Working on frequency 800M Voice services Call ID display Call forwarding Three way calling DTMF Emergency calling SMS Supporting CDMA2000 1X PS data service MSM6025 Being compatible with internal antenna or external antenna external antenna connected with the standard RF connector which can be disassembled Power supply with charge battery...

Page 4: ... detecting storage equipments In additional to control modulation and demodulation to control user interface 5 Background Software Management Modules to write the user configuration information into flash and to replace configuration parameters to different software versions which to meet different operater s requirements 1 2 2 Specification of hardware Working Frequency Band Uplink 824MHz 849MHz ...

Page 5: ...agement subsystem RF subsystem and TCPU interface subsystem the PIPU includes user interface subsystem Serial port protection module AF channel 1 AF channel 2 Environment monitoring module and PCB version number check module power supply and power manager subsystem Primary power supply module Primary power supply check module Battery charge discharge module DC DC power module Power switch control ...

Page 6: ...Power adapter When powering on WL71PIPU the whole process as follows There are two ways of power supply one is battery the other is external power When using the later one VEXT_DC up to 5V then PM6610 begins to work and software startups At this moment some functions of software have been running and the system begins to detect and charge the battery the display of LCD in charging status If holdin...

Page 7: ...e the battery or not The battery is charged or not which by controlling the output current form the secondary power When the battery in fast charging status the grid of Q303 is low and not through The internal differential amplifier TL494 will control the pulse duty ratio of PWM which the current output of switch power supply will be restricted to 830mA when the battery in slow charging status the...

Page 8: ...e secondary power supply 4 4V directly When there is no external power supply battery powers the system supply through the signal VREG_PHONE and there is no special discharging control circuit Audio Interface Circuit ETS2228 audio interface includes handle receiver the microphone and earphone is included speaker interface and hands free MIC interface The power of speaker is quit bigger than the ot...

Page 9: ...er Interface 3 Hands free Interface Circuit The audio amplifier amplifies EAR2 signal to speaker the switch of speaker is controlled by the bias voltage of MIC2_P And when the bias voltage of MIC2_P is zero the voice channel and the audio amplification is shut down which the system is in idle status Possible faults of the hands free channel no ringing then check whether U603 is wrong or not ...

Page 10: ...ge 10 Total 43 Figure 6 Hands free Interface Circuit LCD unit In the ETS2228 FWT LCD is a peripheral component If wrong with LCD it can be replaced directly The PIPU is compatible with the lattice LCD and the segment LCD ETS2228 adopt the lattice LCD ...

Page 11: ...ETS2228 Maintenance Manual All right reserved Page 11 Total 43 Figure 7 LCD Hardware Interface Circuit PIN NO FUNCTION DESCRIPTIONS SYMBOL 1 This is the chip select signal CS1 2 RES 3 A0 4 R W 5 E ...

Page 12: ...al drive The voltage Supply applied is determined by the liquid crystal cell and is changed through the use of a resistive voltage divided or through changing the impedance using an op amp Voltage levels are determined based on Vss and must maintain the relative magnitudes shown below V0 V1 V2 V3 V4 Vss V0 List 2 Lattice LCD Signals Keypad unit In the ETS2288 series FWTs the keypad is a peripheral...

Page 13: ...port and prevents the damage towards the system from abnormal power level input such as ESD Serial port signals are divided into 5 groups 1 Data receiving signal RS_RD Input Data sending signal RS_TD Output 2 Traffic signal clearing sending RS_CTS Input Request sending RS_RTS Output 3 Modem status signal modem refers to FWT Carrier wave detection UART1_DCD Output Data terminal ready UART1_DRT Outp...

Page 14: ... level conversion circuit Figure 3 Output power level conversion circuit Data receiving signal power level conversion circuit The power level conversion of signal UART1_RX is accomplished by clamp circuit The reason lies in that the signal power level needs to be lowered to detect whether or not the serial port line is connected when there are no data lines ...

Page 15: ...ement 1 DC DC power protect module This part is chosen joint circuit the external power over voltage protection module protects the input power When the input voltage exceeds 30V the protection circuit will function Then the silicon controlled thyristor is in the continuity status and the self healing fuse F301 F302 we only need to joint one of them and now we joint F301 will be blown Thus the pow...

Page 16: ...current charging function The maximum output current is 830mA We mainly use the PWM control chip U302 and the switch transistor Q301 to complete the second time switch power circuit It is the switch power supply that converts the external power into 4 4V Figure 5 DC DC Power transfer circuit The PWM control chip adopts TL494 including 2 differential amplifiers 1 external adjustable oscillator 1 pu...

Page 17: ... of the changed external input The external oscillating circuit can be set through Rt Ct The working frequency to be set is 100KHZ 3 Power supply anti reverse insertion circuit and external interface D305 and D301 fulfill the anti reverse insertion function of the external power supply EXT_DC signal Whether or not the external power supply exists V_BATT signal Battery voltage VREG_PHONE signal Vol...

Page 18: ...age limiting module The second time power voltage limiting module limits the second time power voltage to 4 4V When the constant current charging operation is ended the second time power output is stabilized to 4 4V to provide power for the back level circuit The feedback loop is accomplished by operational amplifier 1 of TL494 ...

Page 19: ... The temperature s measure is finished on TTPU veneer and the battery s ID measure is finished on PIPU veneer This module converts the thermistor into voltage and sends the voltage to ADC on the TCPU board to be measured Thus the battery temperature will be measured See the following figure for the circuit Figure21 Battery temperature switchover module ...

Page 20: ...inly includes functions like baseband modulation demodulation and channel coding decoding It also includes the CPU system through which protocol software runs as well as FLASH for storing software and SRAM for running software 3 3 Power Management Part Power management sub system mainly fulfils DC DC converting of external input power and managing power voltage which is used by inside circuit The ...

Page 21: ...prescription of external power supply VCHARGER 1 I V BATT interface PM6610 Stakeout battery voltage directly connect to pole of battery ICHARGE_M 4 I TCXO TCXO PM6610 Main frequency input signal TCXO IN 24 O BUFF TC XO PM6610 MSM6000 Main frequency output signal TCXO OUT 23 I TCXO EN MSM6000 PM6610 TCXO enable signal TCXO EN 25 I PS HOLD JTAG ON MSM6000 PM6610 MSM6000 register unit Control whether...

Page 22: ... VERG TC XO PM6610 TCXO Supply TCXO voltage which produces circuit VERG TCXO 32 O VREF RF RX PM6610 RFR6122 Supply voltage to RFR6122 VREG RFRX 3 1 O VREG MS MC PM6610 MSM6000 Supply digital signal voltage to MSM6000 VREG MSMC 14 O VREG MS MP PM6610 others Supply voltage to kinds of external equipment VREG MSMP 16 O VREG MS MA PM6610 MSM6000 Supply analog signal voltage to MSM6000 VREG MSMA 11 O V...

Page 23: ... difference is RF part 1 Receiving unit Unit function After the duplex module sufficiently suppresses the out of band spurious filter the received radio frequency signals will be sent to the down convert frequency mixer via the radio frequency low noise amplifier and radio frequency SAW filter to experience the frequency mixing operation Since RFR6120 assumes the Zero Intermediate Frequency struct...

Page 24: ...ls are generated after RF Mixer and RF filter function on the signals Then the RF signals are amplified by the RF amplifier so that RF emission signals set with certain output power value are generated Finally after the duplex module sufficiently filters out of band spurious emission signals the signals will be sent to the antenna The other function of the duplex module is to prevent the emission ...

Page 25: ... RF duplex interval is 45MHz Therefore we design the RF oscillator to be shared by both receiving and transmitting operations For both of them receiving and transmission operations the RF local oscillator is high The reference clock signal frequency is 19 2MHz and the phase detection frequency is 25 KHz The Rx PLL circuit is integrated into RFT6122 but RX VCO and RX LO are still in RFR6122 ...

Page 26: ...ides power voltage for PM6610 VREG TCXO provides voltage needed by the clock for RFR6122 VREG MSMP provides voltage for internal RFR6122 components RF local oscillation signals are for receiving transmission channels to conduct down up conversion operations Both channels share the same RF local oscillation signal Rx LO IN VCO TUNE RX FAQ LO OUT Fv TCXO R Counter N RX LO RFT6122 RFR6122 Fr Digital ...

Page 27: ... capability indices 106dBm 1 23MHz 6 Amplitude frequency characteristics 7 Amplitude range 1dB within 1 23MHz After being calibrated 8 double work distance 10MHz 9 channel distance 25 KHz Primary indices of the emission unit 1 Frequency range 824MHZ 849MHZ MHz 2 Maximum emission power 23dBm 3 Maximum linearity output power 28 dBm 4 ACLR requirement 42dBc 30KHZ 885KHZ 1 98MHZ 56dBc 30KHZ 1 98MHZ 4M...

Page 28: ...ncy 19 2MHz 2 Frequency error 2ppm 30 85 3 Output signal amplitude 0 5Vpp min Indices of emitting and receiving intermediate frequency local oscillation signals Zero intermediate frequency method RF local oscillation signals Indices 1 Output frequency 1664 1788MHz 2 Output power 12dBm 2 Electric Indices ...

Page 29: ...est mode Inputting keypad command 10999 to enter factory test mode Press 4 to hands freeing voice loopback Press 6 to handle loopback Press Delete long time to LCD test in which all LCD will light and ring utter afterwards 2 Entering RF calibration FTM mode Open tool software QXDM and input mode offline d in command window to modify 453NV as 1 0 for normal mode ...

Page 30: ...nce procedure Figure 11 Power fault maintenance procedure YES YES YES YES YES NO NO power on and startup Check if Q301 is good Chiefly check if CE junction of Q301 is good Check if TL494 U302 is good Check if the voltage of foot 4 of U302 is 5V Check if the voltage of foot 4 of U302 is 1 25V Check if R312 0 1ohm is good Check if D304 is good End NO NO NO ...

Page 31: ... YES NO power on and startup Is the voltage of pin 10 of J404 is 2 84V Check if the clock output of pin 3 of X501 is 19 2MHz Check if the clock signal on the channel of X501 is normal End NO NO Any 19 2MHz clock signal on E17 of U701 Any clock signal on TP801 Is LCD normal Download software again or replace TCPU NO Check the LCD interface signal of PIPU and restore the LCD NO ...

Page 32: ...wer on and startup Does LCD respond after the key is pressed Check if keys are reliably connected with the keypad and remove faults End NO Doed LCD show value of the key pressed Does the keypad respond to data corrrectly Replace the keypad or the mechenical part upper lid on the fixed station NO NO Check inter board connection power and replace the fault cable YES YES ...

Page 37: ...TS2228 Maintenance Manual All right reserved Page 37 Total 43 2 RF Processing Module Fault Maintenance Procedure 1 RF Channel Fault Maintenance Procedure Figure 18 RF Channel Fault Maintenance Procedure ...

Page 41: ...2T 6PIN S101 39040062 Audio Frequency Circuit MC34119D Amplifier Of Telephone Application 2V to 16V SOIC8 Tape U603 39110327 Control Chip PWM Controller SO16 Mobile Dedicated U302 51620041 DKBA8 035 1320 Shielding Box 6025 Module 450M 51620042 DKBA8 035 1321 Shielding Box Cover 6025 Module 450M 13080003 Duplexer 824 849MHz 869 894MHz 2 1dB 2 8dB 21dB U101 39110306 Voltage Regulator 3 0V 3 0 15A SO...

Page 42: ...2020102 TCXO 32 768KHZ X601 39080088 Operation Amplifier Headphone Audio Power Amplifier with Digital Volume Control 2 0V 5 5V 1MHz Stereo LLP Terminal Dedicated U602 7 2 Schematic Circuit Diagram 7 3 Mainboard Structure Diagram Please refer enclosed pages for BOM Schematics Silk Screen 7 4 Test Point Location Diagram ...

Page 43: ...ock loop ACLR Adjacent channel leakage power radio RF Radio frequncy LCD Liquid crystal display LNA Low noise amplifier CDMA Code division multiple access PCM Pulse coded modulation USB Universal serial bus UART Universal Asynchronous Receiver TCXO Temperature compensated crystal oscillator Rx Receive Tx Transmit ...

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