电路如下
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实际电路中C3 为4.1uF的胆电容,R1为3W\52 OHM的电阻( 实际是用了若干电阻并联) .理论上计算I1大概为311/{PI*(R1+1/2*pi*f*C3)}=113mA.但实际上测得只有8mA左右.十分奇怪,难道是C3提供不了这么大的电流?
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