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¢Ú, data buffer (LRS1306) is a more special chip that has Flash and SRAM data storage area inside the chip data cache , in the rewriting of LRS1306 mainly within the Flash chip area rewritten , but in Removing LRS1306 , because the temperature is too high or the programming voltage properly, can easily damage the SRAM area LRS1306 inside , causing no power failure, there are many LRS13306 chip on the programmer can write data to the Flash area to normal , but replace the handset on the still can not boot, mainly for this reason.
¢Û, chip (EEPROM, 24LC64, XI4645), there is a chip inside the phone 24LC64 and XI4645 two models , because the two chips have inherent chip ID number, although the two chips , like the feet and capacity , However, the two types of chips for each can , the software parameters of the chip can not substitute each other , mainly in the Flash system version data set corresponding to the chip using the ID chip .
Second, caused by a hardware failure does not boot
The main part is to adjust the output power , open welding 13MHz clock oscillation circuit part and components caused . Were treated as follows :
¢Ù, the power to adjust the output part is REF3.2V, reference 3.2V, logic 3.2V, IC socket power adjustment controls are not normally cause no power failure , the output voltage is not normal adjustment pipe replacement, failure can be ruled out.
¢Ú, 13MHz 13MHz oscillator oscillation circuit is mainly composed of modules and external rotation adaptation circuit. Shuaiguo phone easily damaged resonant 13MHz 13MHz crystal oscillator module within the testing process must be using an oscilloscope and spectrum analyzer like the testing equipment, using only frequency measurements, the output intensity can not be measured 13MHz clock frequency ; from 13MHz 13MHz clock oscillator module output signal strength of about 100mVpp about adaptation after amplification is about 1Vpp, if the strength is not enough 13MHz output clock signal will not cause power failure is detected when the output intensity of the 13MHz clock signal is low when coupling the output of the circuit should be checked bypass circuit , coupling capacitance resistance if there is leakage, absolve phenomenon .
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