6.2.7 Camera Test & VGA Camera............18 6.2.8 Check SIM ..................20 6.2.9 Battery Test..................21 6.2.10 SDRAM Test ..................22 6.2.12 Turn On/Off Radio................25 6.2.13 Version Check.................. 27 6.2.14 Keypad Test ..................27 6.2.15 WiFi Board-Level Test ..............29 ASUS Proprietary...
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10.3 TX M .................. 43 EASUREMENT 10.4 T :..................45 EST PROCEDURE 10.5 WCDMA RX ..................51 10.6 WCDMA RX P ............53 EASUREMENT 10.7 RX T ................54 EST PROCEDURE 10.8 WCDMA PA P .............. 60 OWER ONTROL ASUS Proprietary...
Expansion Slot Micro-SD (SDHC supports) GPS (SiRF III with internal antenna), AGPS (need to co-work with local operators) , TMC (optional cable) JAVA J2ME (CLDC 1.1 + MIDP2.0) Camera 3 Mega-Pixel (Auto focus) Audio MP3, WMA, AAC, AAC+, 3GP ASUS Proprietary...
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128-ch Polyphonic ringer & MP3 PIM/Utilities Notes, Calendar, Alarm, and Windows Live Messenger, Word (editor), Excel (editor), and Power Point (viewer) Advanced Ur Time, Backup, ASUS Launcher, Voice Commander, Bluetooth Remote Presenter, Travelog, Location courier, Business Card Recognition, Newstation, Meeting planner,...
華 碩 電 腦 華 碩 電 腦 GTC ■ Service Manual 5. Equipment List 5.1 Ha rdware Power source: pow er supply (Monitor current) igital Phosphor Oscillo scope igital Meter ASUS Proprietary...
“Power-On Sequence” issues. First, we can check the Current of the device during the OS booting process then try to measure the “Power ON Sequence”. In P750 design concept; The System will auto Power On in two conditions One is first connect to device, another the voltage drop below 2.8V...
6.1.3 NAND Flash In Item 2, if the d ata can’t response from TP28 ( SD15 ), in my opinion is try to re-flash the data to NAND flash via JTAG. Figure 1. PMU ASUS Propriet...
CON1, the main of the reason should be CPU NG. F. V_LED If the backlight can not active on the LCD panel, w e should measure the 12V on the “V_LED”. If not then check the relate components o the U48. ASUS Proprietary...
We can measure the 32.768 for X2 clock signal. We can try to replace the CPU and X2 on this item failure. 6.2.4 Storage Test It should be U6 (Flash m emory) on soldering issue or com ponent defective. ASUS Proprietary...
CPLD which will cause the RGB LED always illuminated red light. Please replace the CPLD o n PCB. If one of the colors can’t works on RGB LED, please check the soldering issue on R621, R622, R623 or replace the LED6 ASUS Proprietary...
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電 腦 華 碩 電 腦 GTC ■ Service Manual Figure 5. Indication LED Circuit B. Keypad LED failure Please measure the U88.4 (KEY_LED_EN) ->2.9V,if the result is true please check the U88. Figure 6. Keypad LED power ASUS Proprietary...
The CPLD control signal a. 3M: SENSOR_2M_PD = 0V, SENSOR_2M_RST# = 2.9V, SENSOR_2M_CLKEN = 2.9V b. VGA: SENSOR_VGA_PD = 0V, SENSOR_VGA_RST# = 2.9V, SENSOR_VGA_CLKEN = 2.9V If the signal is abnormal please try to change U600 ( CPLD). ASUS Proprietary...
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華 碩 電 腦 華 碩 電 腦 GTC ■ Service Manual Figure 8. Camera control signal ASUS Proprietary...
Figure 11. Charger IC circuit Can’t read the battery ID Check the HDQ_TXD#_PLD and HDQ_RXD_PLD signal. The signal will be detect for a period on the correct status. If the can’t detect then should re-place the U600 (CPLD) NG. ASUS Proprietary...
6.2.10 SDRAM Test If we can execute the MMI tool,SDRAM should be normal. If the result is fail, please also check the U7/U8 relative the signal. C. nSDCS0 D. nSDCAS, nSDRAS E. SDCKE1 F. SA12, SD15 Figure 13. SDRAM circuit ASUS Proprietary...
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First check the voice signal on MIC_HEADSET_R. If didn’t work please check the component (R55, R57, C120, C112, C123). F. Can’t Exit the headset mode Please check HP_DET ->0V,If the answer is not please refer to item A. ASUS Proprietary...
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Figure 15. Class D Amp for speaker B. On-Board Microphone can’t Record If the quality is poor please change the U11. If the function total un-work please check the (L1, C121, C124, C125, 126). Figure 16. Microphone circuit ASUS Proprietary...
Modem Power G. CCPU_VCC-> 3.6V. if not please check the U75 (Step-Down Converter). Figure 18. Step-down converter for modem power H. Check below item VDD_1V5 1.5V VDD_1V8 1.8V VDD_2V75 2.75V VDD_2V85 2.85V ASUS Proprietary...
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Modem to System Interface The main of the purpose is level shift on CPLD between Modem and System. We can check the component (R711 ~ R715, R763 ~ R766), If the result is normal then try to change the U600 (CPLD). ASUS Proprietary...
A. Board level test The specify key include(joy dial up, joy dial down, joy dial action, 4, 8, clear, #) The P750’s keypad matrix contain for (row * 6, column*5). At least we need 6 buttons to fully cover each trace, it is weak for joy dial on 3 XYZ direction test.
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Keypad IC for itself. If the “interrupt#” and “watchdog reset#” are0~2.6V, it always cause abnormal on U90. We can try to re-heat the chip U90 or replace it. Figure 21. Keypad driver circuit Figure 22. Keypad matrix ASUS Proprietary...
The power of the chip is well. We still can’t get the signal from GPS_TX, GPS_RX. Please check the R1011 -> 47K ohm? If the answer is true then try to change the U600. 6.2.17 PS Board-Level Test Follow the test item 16. Figure 23. GPS power ASUS Proprietary...
(U20). If the result is NG please check the below item. BT_VCC_3.3V R104, R111 USB signal R102, R104, R110, R111, R112 USB protocol check If all of item is pass , please re-work the chip U20. Figure 24. BT connection ASUS Proprietary...
CPU. After remove the resistor R217 we can use the power meter to measure the current on the circuit. The reference value is below 10mA. If over the value we can try to change the CPU to extend the idle time. Figu re 25. VCC core source ASUS Proprietary...
U951 NG. The U951 is response DC/DC converter to Modem power amplify. Try to remove the R951 and detect the system’s power current from the power supply. If the answer is true please replace the U951. Figure 26. DC/DC converter for wideband PA ASUS Proprietary...
華 碩 電 腦 華 碩 電 腦 GTC ■ Service Manual 9. RF Block Diagram RF FEM Signal True table The value “1” means level High , “0” means Level Low. ASUS Proprietary...
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華 碩 電 腦 華 碩 電 腦 GTC ■ Service Manual E-GSM 900 Power (PL5) ASUS Proprietary...
The output power passes through coupler (U955), isolator (U954), duplexer (U956), to the T/R switch (U901) on the FEM (SKY77513). Finally the power will radiated via matting circuit and connector (Con900). WCDMA TX Schematic path ASUS Proprietary...
Spectrum Setting: Freq=1950MHz. Caution: Must add the attenuator/DC Blocking or series connection 100PF Cap on the end of the Cable. It will avoid the direct current damage the spectrum authentically. The Power values all are relativity not absolute. R968.1 ASUS Proprietary...
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華 碩 電 腦 華 碩 電 腦 GTC ■ Service Manual C975.1 ASUS Proprietary...
WCDMA TRANSMITTER IC RF3100(U950) PIN X1_A ,MX1_B again. After down converting the signal’s frequen cy and transforming into IQ signals, the IQ signals (WRX_I_P, WRX_ I_N, WRX_Q_P, WRX_Q_NMAX2391) travel to Base Band IC DB3150 (U701). WCDMA RX Path Schematic_1 ASUS Proprietary...
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華 碩 電 腦 華 碩 電 腦 GTC ■ Service Manual MA RX Path Schemat ic_2 ASUS Proprietary...
B. Launch the P_E_Tool. Click the CDMA TX mode. C. Choose Com Port D. Choose Band I (Pegasus Pro Only Band I ) E. Choose WCDMA RX F. Setting the WCDMA RX channel, please set the Agilent 8960 to CW mode .The power: -30 ~ -40dBm ASUS Proprietary...
Setting: Fre q=2140MHz. Caution: Must add the attenuator/DC Blocking or series connection 100PF Cap on the end of the Cable. It will avoid dire t current damage the spectrum authentically. The Power values all are relativity not absolute. R983.2 ASUS Proprietary...
RF_DAC1 and RF_DAC2 used to the Power level control by (PA and DC/DC converter). WPOW DET EN Power WPOW_DET DC/DC WDCDC_EN Couple WCDMA From RF3100 TX Output WB+EGG Digital BB CTRL_DATA WCDMA CTRL_StrB Controller Transceiver CTRL_Clock DB 3150 WBCLK ASUS Proprietary...
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華 碩 電 腦 華 碩 電 腦 GTC ■ Service Manual ASUS Proprietary...