cpu供电电路原理及检修流程（Principle and maintenance process of CPU power supply circuit）.doc

cpu供电电路原理及检修流程(Principle and maintenance process of CPU power supply circuit)
The display is not bright, maintenance key in the main CPU power supply circuit, CPU main power supply circuit is an area most easily damaged during the repair process, it damaged the test card can display FF00, motherboard power, but the CPU does not work, because the CPU needs a stable supply current, in order to work.
CPU main power supply damage characteristics, such as cafes, individual users, user units can be seen around the bulging capacitor leakage, explosion proof capacitor tank exploded, received such a motherboard, first will replace capacitor bulge leakage, replacement of the pressure value can be larger, the capacity can be error more than 20%.
Field effect tube breakdown and the use of a multimeter on the buzzer file can determine which field effect transistor is breakdown. By measuring the interface of ATX power supply, the value of the earth can be judged as 5V, not 12V breakdown, according to the characteristics of the capacitor.
General CPU main power supply circuit, all related circuits are set near the CPU socket. The main power supply circuit will not be installed anywhere on the motherboard.
Voltage identification pin VID0 - VID4, that is to say, how much voltage is needed for CPU and how much current is needed. If the CPU needs P3 voltage P4CPU voltage is slightly high, need relatively low, according to the needs of different voltage
frequency of CPU is the same, so the motherboard CPU need to how much voltage needed to tell their own information power management chip, power management chip after internal programming, the need to correct voltage output CPU. Know how much CPU supply voltage, download the bottom view of the CPU itself, which has taught you how to measure CPU power supply.
The whole process: the main power generation circuit posed of power supply control chip (CPU chip U1 power supply), sound effects (including tube field effect transistor Q1