What If The U Disk Is Plugged Into The Machine Without Any Reaction?
What if the U disk is plugged into the machine without any reaction?
Maintenance idea: According to the fault phenomenon judgment, u consolidation machine does not work, and U disk tools to have the conditions that we maintain the focus. Regardless of any scheme of the U disk want to work must have the following conditions:
(1) power supply, divided into the main control required by the power supply and flash required by the power supply, these two are the key, and U disk circuit is very simple, such as no power is generally the insurance inductance damage or 3.3V Voltage regulator block damage, when it comes to the voltage regulator here again, it has three pins respectively is the Power input (5V), the ground, the power output (3.3), the work principle is when the input foot input a 5V voltage, the output pin will output a stable 3.3V. As long as you find out where there is no power source, the problem will be solved.
(2) The clock, because the master control to work at a certain frequency, with flash communication also want to * clock signal transmission, so if the clock signal is not, the main control will not work. And in the examination of this aspect of the circuit, in fact,U disk the clock generation circuit is very simple, only need to check the crystal oscillator and its peripheral circuit, because the crystal is afraid of the brush and the small disk is easy to fall on the ground caused by crystal damage, as long as the same crystal vibration can be replaced. Note: Crystal oscillator is not measurable, the best way to judge its good or bad is to replace a fine crystal to judge.
(3) Master control,U disk if the above two conditions are normal that is the main control chip damage. Just replace the master control.