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1.用试验电源给机器供电的时候,按“开机”按钮后有开机电流(100mA左右),但是放开按钮后,电流就下降为零,实际是接近于零为几十微安故障分析与检修:该故障一般是开/关机电路的三极管电流放大倍数太小或者三极管损坏,当按“开机”键时,“PLAYON”(放像键接通)应该为接近电池电压、“PWRON”(电源接通)应该为高电平(3.3V),如果该两点电压异常,通常是三极管损坏,或者就是BAV70
1. With the test power supply to the machine, press the “Power On” button after the boot current (100mA or so), but after the button is released, the current drops to zero, the actual is close to zero for tens of microamperes failure Analysis and Maintenance: The fault is usually on / off transistor circuit current amplification is too small or transistor damage, when press the “power on” button, “PLAYON” (play button connected) should be close to the battery voltage , “PWRON” (power on) should be high level (3.3V). If the voltage at the two points is abnormal, usually the transistor is damaged, or the BAV70