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2EYservice manual download site
(2), data cache (LRS1306) is a relatively special chip, chip inside the Flash data storage area and SRAM cache data area, when to rewrite LRS1306, main is to rewrite the Flash chip area, but when removing LRS1306, due to improper temperature too high or programming voltage, easy to damage within LRS1306 SRAM area, cause not boot failure, there are many LRS13306 chips on the programmer to write data to Flash area normal, but reply unit still cannot boot, mainly is for this reason. 2EYservice manual download site
2EYservice manual download site
(3), the code block (EEPROM, 24 lc64, XI4645), 24 lc64 and XI4645 inside the phone chips have two kinds of models, because the two have inherent within the chip ID number, although the two kinds of foot, and capacity of the chip, however, these two types of chip cannot be used for each other, the software parameters of the chip also can not substitute each other, mainly within the system version of Flash data set corresponds to the chip ID number use piece of code. 2EYservice manual download site
2EYservice manual download site
Second, no boot failure caused by hardware 2EYservice manual download site
2EYservice manual download site
Mainly the power adjustment output part, 13 MHZ clock oscillation circuit caused by open welding of parts and components. Respectively as follows: 2EYservice manual download site
2EYservice manual download site
(1), power adjustment output part mainly REF3.2 V, 3.2 V, 3.2 V logic, jack IC power supply adjustment tube caused by abnormal not boot failure, adjust the output voltage is not normal tube replaced, the fault can be ruled out. 2EYservice manual download site
2EYservice manual download site
(2) and 13 MHZ oscillation circuit is mainly made up of 13 MHZ oscillator module and outer adapter circuit. Fell a mobile phone is easily damaged 13 MHZ 13 MHZ resonance crystal oscillation within a module, in the process of testing must be use the oscilloscope and spectrum instrument testing instruments, such as only use frequency meter measuring, cannot be measured 13 MHZ clock frequency of the output intensity; From 13 MHZ oscillation output module 13 MHZ clock signal intensity is about 100 MVPP, amplified by adaptation after approximately 1 VPP, if 13 MHZ clock signal output intensity is not enough also can cause boot failure, when detected 13 MHZ clock signal output intensity is low, should check the bypass circuit in the output coupling circuit, coupling capacitance resistance to see if there is leakage, perfect phenomenon.
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