The customer has the stricter requirements for quality of phone

The customer has the stricter requirements for quality of phone .
Very simple, MTK unlock the address of a friend should know, 4M, 8M, 16M, and so on. This repair method is to update the chip data, in general, the software under normal use conditions, are caused by the chip failure, so we adopt this solution to a fault caused by the chip data, this address to clear into the FF, then put it back pressing power chip data will re-establish, so that does not resolve? But you write software to back up in case of bad, the fixed version when to have it fixed, can not let it open back up, and then unlock. CPU for low power failure in MT6205.6217.6218.6219 kill. Sales Department organized the meeting to discuss the technical problem of phone in the meeting room 1.
Many domestic machine CPU is MT6205. This CPU is very powerful, fault, one of the most common boot low battery, then shut down. This failure causes the CPU battery detection feet do not get the battery data, that is the power of the CPU pick the measured foot to the battery + problem, and they are mostly connected by an exclusion (1004) , exclusion deterioration or false welding causes up to bad, the CPU board break. 6205 the power to pick up the measuring pin D6, A6 (charge capacity pick test) 6217,6218,6219 the power to pick the measured foot the D6, C6 (charge capacity pick test)]. MP3 phones sound classic kill. The working instruction of this kind of phone has the second version.
The failure of all the head is the ringing amplifier Weld, a long time listening to music, the amplifier heat caused by the Weld. The amplifier is very small glass film welding time to pay attention, remember the direction of the IC and the high temperature should be removed and then remove the plastic and then welding. The MT series emission shutdown solutions. Launch shutdown, the first power source tone 4 5V or so, try to see the launch will not shut shutdown, if the shutdown, bad amplifier. If you do not shut down, the amplifier is not bad, personally think that should still be IF and CPU. The inspection group is carefully inspecting the working instruction of phone .
When the boot trigger signal, power IC voltage regulator output should voltage output. Boot to maintain signal (watchdog signal) is turned on to maintain signal from the CPU, power IC, only to get the boot to maintain signal to output continuous voltage, otherwise, the phone will not be able to continue to boot. Logic circuit is working properly. Normal power supply. After pressing the start button, the power supply voltage of IC output stability, logic circuitry, including the CPU chip, font and register. Normal system clock, the clock is the basis of the data processing of the CPU according to the beat of the phone are two of the clock circuit, a clock VCO module containing the components of the oscillator circuit and crystal, when the power switched on, self-oscillation. the formation of the 13MHZ signal output. phone can work more efficiently for the new technology.