Samsung STH-N375 Service Manual Download

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SERVICE

TDMA MOBILE
TELEPHONE

STH-N375

Manual

TDMA MOBILE TELEPHONE

CONTENTS

1. Trouble Shooting

2. Electrical Parts List

3. Exploded Views and Parts List

4. Block Diagrams

5. PCB Diagrams

6. Circuit Description &

Circuit Diagrams

Summary of Contents for STH-N375

Page 1: ...MA MOBILE TELEPHONE STH N375 Manual TDMA MOBILE TELEPHONE CONTENTS 1 Trouble Shooting 2 Electrical Parts List 3 Exploded Views and Parts List 4 Block Diagrams 5 PCB Diagrams 6 Circuit Description Circuit Diagrams ...

Page 2: ... Samsung Electronics Co Ltd May 2002 Printed in Korea Code No GH68 02790A BASIC ELECTRONICS ...

Page 3: ...check U110 U111 U206 N Need to replace Memory U202 N Need to check TCXO OSC302 neighbor part Press END Key Y Y Y Y Y Y ON_SW H VBAT 3 2V VCTCXO_IN 14 4 MHz Memory U202 control signal OK VCC 3 0V V_VCTCXO 3 0V RESET 3 0V IVCC 2 2V GBOOT_DI H Program Running VCC ADD 0 21 DATA 0 15 FLASH_CS SRAM_CS UBE MEMOEB MEMWEB N ON_SW H Need to check Key Mat Need to check Battery ...

Page 4: ... 7 DISPLAY_CS RESET LCD Display Running Send Command Back Light enable Y N Need to check R216 U205 Y LCD Display Running Back lingt Running Send Command Vibrator enable Need to check Q109 R130 R162 R163 R164 START Y Y N Need to check U101_77 79 Y LCD Display Running Back lingt Running Vibrator Running Send Command Main Audio Receiver Path ON Send Command Audio tone generator ON 1 VIBRATOR H Vibrat...

Page 5: ...ice 1 3 STH N375 Trouble Shooting 1 3 Abnormal Buzzer operation N Need to check Q207 D201 U101 START Y Y Send Command Ringer Path ON Send Command tone generator ON N Replace AU201 Y Y Buzzer Sound Output OK RINGER U101_1 Signal OK Buzzer Operation Good ...

Page 6: ... external Ear_Mic Jack operation START Y Y Hock Up Ear_Mic Phone in the Jack CN101 Send Command MIC_BIAS_EN enable Send Command AMP_EN enable N Need to check U106 neighbor parts Y HS_SENSE H N Need to check U106 neighbor parts Y Y SEND_END H Press Button on the Ear Jack Ear_Mic phone Operation Good ...

Page 7: ...out notice 1 5 STH N375 Trouble Shooting 2 RF Section 2 1 Call processing and Online Test N DONE START Y Y Normal SVC Check RX path N Y Set up Call OK Check TX path N Y Measure SINAD BER Good Check RX path N Y Check TX path Measure Tx Power Good ...

Page 8: ...heck F302 neighbor parts Y RF_BAND L RX_BAT H PLL_ON H PON_LC H VCTCXO_PC H IF_ON H PON_VRF3 H set up 8920B basestation for RX test Set Base station RX Lev 50 dBm Send Command Cell band selection Send Command RX path ON Send Command channel selecton START N Y V_LNA_CELL H U105_1 H Q102_3 H Need to check U300 neighbor parts 2 U301_45 39 5dBm N Need to check C324 F303 F303_3 U300_8 55dBm F302_2 36 0...

Page 9: ...rts U301_1 2 3 Need to check U105 neighbor parts N Y Y Y Y Y RF local check U301_48 Lev 6dBm Freq adjusted freq 1 U301_41 Lev 24 5dBm Freq 130 05MHz U301_34 Lev 28 0dBm Freq 130 05MHz Need to check U301 L301 C304 C306 R301 Y Replace F300 or Need to check R302 R303 C303 U301_25 Lev 18 0dBm Freq 450kHz MODE U301_40 42 3 0V 4 3 N U301_37 Lev 13 0dBm Freq 450kHz N ...

Page 10: ... PON_LD H Case AMPS mode setup basestation for RX test Audio Freq gen 1004Hz FM deviation 2 9kHz 4 Y Y Y U301_16 DEMOD sinusoidal wave Vp p 240mV Freq 1004Hz N Need to check U301 R326 R320 C352 C127 U101_52 DEMOD sinusoidal wave MAX Vp p 1 4V Freq 1004Hz N Replace U203 Y U101_40 BBCLK 6 2208MHz or 4 096NHz or 5 12MHz N Replace U203 Y U101_32RX_CLK BBCLK 2 or BBCLK 8 N Replace U203 Y U101_31 RX_SYN...

Page 11: ...Y U101_40 BBCLK 6 2208MHz or 4 096MHz or 5 12MHz Y U101_34 TX_CLK BBCLK 32 or BBCLK 8 Y U101_33 TX_SYNC BBCLK 512 or BBCLK 128 Y U101_33 TX_DATA serial data RF_BAND L TX_BAT H PLL_ON H VCYCXO_PC H IF_ON H PON_TX H PON_VRF3 H setup 8920B as basestaion for TX test audio signal Send command cell band selection Send command TX path ON Send Command channel selection START AMPS TDMA 2 1 MODE ...

Page 12: ..._61 60 58 57 TX I Q Quarature signal AC Lev Vp_p 0 4V DC bias Lev 1 5V U101_63 MOD sinusoidal wave MAX Vp p 1 4V Freq 1004Hz OSC303_1 FM modulation out Freq 175 05MHz Audio Freq 1004Hz Need to check OSC303 V_IF_VCO 3 0V N N N N Y Need to check U301_66 or Replace U304 U301_59 RF OUT measure Level Send command PA_CNT Level is adjustable N Y Replace F306 U301_59 RF OUT Fc Local_freq 175 05 N Y ...

Page 13: ...5 U305 Gain around 27dB N Y Replace F305 F305 Insertion loss around 3dB N Y Need to check V_PA_BAIS_CELL U302_5 6 7 3 0V VBATT U302_14 15 16 3 2 4V or Replace U302 U302 Gain around 30dB N Y Need to check F304 neighbor parts F304_1 around same power with U302 output N Y Need to check F304 neighbor parts F303 insertion loss under 3dB N DONE ...

Page 14: ...SAMSUNG Proprietary Contents may change without notice 3 1 3 STH N375 Exploded View and its Parts List 1 Cellular phone Exploded View 1 3 4 5 7 6 8 9 11 13 13 15 12 10 2 4 1 ...

Page 15: ...NECT ANTENNA REAR COVER SCREW DUMMY SCREW M1 7 x L3 5 RF JACK COVER BATTERY 2 Cellular phone Parts List 1 2 3 4 4 1 5 6 7 8 9 10 11 12 13 14 15 Description Remark SEC CODE Silver Location No 900mAh GH75 01724A 3001 001210 GH75 01826A GH82 00107A GH07 00143A GH73 01024A GH59 00376A GH75 01895A GH31 00019A GH73 01026A GH42 00141G GH72 03845A GH73 01130A 6001 001319 GH73 01027A GH43 00490A ...

Page 16: ...d its Part List SAMSUNG Proprietary Contents may change without notice 3 3 3 Test Jig GH80 00614A 4 TC GH44 00145G 110V Mexico Colombia Brazil Serial Cable Power Supply Cable 5 RF Test Cable GH39 00090A 6 Test Cable GH39 00092A ...

Page 17: ...AD OSC301 TCXO 14 4MHz EXT SYSTEM RF IF AGC_OUX RX_I RX_IX RX_Q RX_QX DEMOD A_IF_I RSSI MOD TX_I TX_IX TX_Q TX_QX TX_PWR PA_CNT AFC_OUX AUDIO IF REC2O REC2O MIC MIC RAUXO XAUX PA_GATE ALC_EN RX_BAT TX_BAT PLL_CLX PLL_DATA PLL_STRB PREAMP_G Digital SignalX BBCLK RX_CLK RX_DATA RX_SYNC TX_CLK TX_DATA TX_SYNC RST WBDRX WBDTX SI2 SO2 SCK2 BEC IF PART EXT AUDIO AMP U102 DISPLAY GPIO s TCXO_I N UART AUX...

Page 18: ...m 2 1pF CFUXC450B100H F300 IL 4 5Typ 6 0Max GD us 5Typ 15Max Zin out 2k VC TCXO 14 4MHz Toyocom TCO 9133 OSC302 Current drain 1 5mA Max Output level 0 8Vpp min Load 10kOhm 10pF PN dBc 130 100Hz 152 45kHz 129 6MHz 999 09 1024 02MHz 2060 1 2120 04MHz 450kH z BPF 824 849 RF2376 U305 G dB 24 27 30 836MHz Current mA 30Typ ACP Leakage dBc 33 8dBm Pout 30kHz offset 61 8dBm Pout 60kHz offset NF dB 7Max Qu...

Page 19: ...6 D207 D208 D209 D210 D211 D212 D213 G1 G2 G3 G4 G5 G6 G7 G8 L101 L102 L104 L105 MIC101 P201 P202 P203 P204 P205 P206 Q105 Q106 Q107 Q108 Q203 Q204 Q206 R102 R107 R111 R116 R121 R124 R128 R130 R132 R135 R143 R144 R145 R146 R147 R148 R149 R150 R151 R152 R153 R162 R163 R164 R208 R210 R215 R216 R219 R236 R240 R241 R244 R246 R247 R249 R250 R251 R252 R253 R254 RV204 S202 S203 S204 S205 S206 S207 S208 S...

Page 20: ...9 C410 C411 C412 C413 C414 C415 C416 C417 C418 C419 C420 C421 C422 C423 C424 C425 C426 C427 C428 C429 C430 C431 CN101 CN201 CN202 D301 F300 F301 F302 F303 F304 F305 F306 L300 L301 L302 L303 L304 L305 L306 L307 L308 L309 L310 L311 L312 L313 L314 L315 L316 L317 L318 L319 L320 L321 L322 L323 L324 L325 L326 L327 OSC301 OSC302 OSC303 Q101 Q102 Q104 Q109 Q202 Q207 Q208 R101 R103 R104 R106 R108 R109 R110...

Page 21: ...C IFC Interface Chip U101 For the POWER OFF in this case main application program is running already The main application program check all GPIO inputs periodically The END key is pressed during program run the BATT and ON_SW signals will be connected This turns on Q108 Therefore ON_SW_SENSE that is connected to GPIO_0_5 U203_ C13 turned logic high to low The BEC checks this signal main applicatio...

Page 22: ...SAMSUNG Proprietary Contents may change without notice 6 2 STH N375 Circuit Description Circuit Diagrams Figure1 BEC interface and block diagram ...

Page 23: ... SRAM_CS FLASH CS DISPLAY_CS UBE etc GPIOs and the communication ports The communication ports includes UARTI UART2 JTAG and SCI The UARTI supports HP equipment interface down loading and data service The UART2 and the JTAG are used for the software debugging The SCI ports support the diagnostic monitor DM function FLASH ROM inside of U202 The 16Mbits FLASH ROM is used to store code of the applica...

Page 24: ...uits in the IFC to minimize noise pickup The speaker output is amplified internally to enable direct connection to the speaker The second audio path connects to the headset jack The headset microphone and speaker are passed to the IFC s auxiliary input and output respectively The headset jack terminals indicate via the HEADSET SENSE line when the headset is present as well as when the headset butt...

Page 25: ...1 Transmitter interface The U101 receives TX DATAI U101 36 synchronized by control signals TX SYNC TX_CLK U101_33 34 which come from BEC and translate this data as differential l Q signals TX_IN TX 1 TX_QN TX Q U101_61 60 58 57 or MOD signal U101_63 it transports these data to RF modulation part In addition the U101 uses PA CNT U101_73 TX PWR U101 68 for controlling power of transmitter AUDIO CODE...

Page 26: ...hecking the RSSI through U101_69 U203 decides to whether turn on U300 or not The amplified signal goes into F302 RF SAW filter in order to suppress the unwanted band data The signal coming out from F302 inflows to the pin 45 Ist Rx mixer input of U301 and it is downconverted to the IF of 130 05 MHz This 1st mixer has around 7dB conversion gain 6dB NF and 5dBm IIP3 For the downconversion the local ...

Page 27: ...iter goes into the discriminator or quadrature detector of U301 with incorporation of the quadrature tank circuit LC resonator placed outside of U301 and thus the audio signal comes out from the pin 16 of U301 This demodulated signal is connected to U101 TDMA Rx AGC and 1 Q Demodulator The downconverted signal from the output of F300 enters to the Rx AGC and 1 Q demodulator of U301 The Rx AGC has ...

Page 28: ... Regulator Rx AGC Gain step RX_BAT BEC RFIC Various Receiver power control TX_BAT BEC RFIC Various Transmitter power control ANALOG_DIG BEC Various Band control 0 Analog 1 Digital LOCK_DET RFIC BEC PLL lock detect status PLL_ON BEC Regulator PLL power control V_RF1 RFIC A_IF_IN RFIC IFC IF comparator input RX_Q RX_QN RFIC IFC Differential analog receive Q channel RX_I RX_IN RFIC IFC Differential a...

Page 29: ... C138 100K 6 8NF C139 C141 100NF R133 10 R138 1 8K R107 330K 1 VCC 2 3 1 C121 27PF Q101 U106 2 L104 NC C185 82nH R116 16V 2 2UF C171 VIN 1 5 VOUT 100NF C145 U107 LP2985AIM5 3 3 4 BYPASS GND 2 ON OFF 3 4 7NF C127 100K 6 3V 10UF C165 VBAT R144 R135 10K 1UF 6 3V C151 15PF C175 C160 10UF 1UF C149 C108 100NF Q102 100NF C170 C168 100NF VCC 6 3V 2 2K R103 C159 C158 10UF 6 3V 10UF C131 36K R122 22PF R143 ...

Page 30: ...A9 R6 E3 AGND G13 ALC_EN K13 A16 A17 R9 P9 A18 A19 N9 R3 A2 R10 A20 A21 P10 A3 N4 P4 A0 A1 P3 P6 A10 A11 N6 R7 A12 A13 P7 N7 A14 A15 P8 N8 U203 B2 32K_XIN 32K_XOUT B1 R2 C229 S206 2 3 1 100NF P204 Q204 6 SW201 1 5 4 3 2 7 8 R211 100K 5 1K R240 U206 2 GND SRT 1 VCC1 4 3 VCC2 _RESET 5 R212 330K VCC VCC C209 100NF S215 CN202 1 BIT 03S AU201 ZD210 RB751S 40 100NF R218 20K C216 VC040205X150R RV202 ZD20...

Page 31: ... C304 5 6NF C375 560 100NF 100K R339 C394 RFOUT 6 VCC L311 6 8nH U305 GC 3 2 GND GND 5 4 RFIN 1 GND 2 GND 7 8 RFIN1 6 RFIN2 1 RFOUT1 RFOUT2 3 U300 4 EN1 EN2 5 1 G G 3 4 G G 6 2 IN 5 OUT F302 470 C349 100PF R307 4 7uH L315 27ohm R324 1 8PF C396 C359 56PF R309 270 2 2NF C352 5 3 4 1 2 U304 L304 120nH R365 1K 82nH C388 100PF L326 C348 C301 100NF 2PF L310 8 2nH 10NF C379 6 8nH L324 R364 10 12nH L323 R...

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