主要问题在于驱动电路(555)拉低后,开关管基极电压下不来,导致过热.
已经试验过的方案有(未奏效,或效果不明显)
1.在基极电阻上并二极管,并电容
2.在C极和电源间加二极管串电阻
3.在ce间加电容串电阻
4.在b极加一个pnp三极管到地,基极直接555输入
实在不知道问题出在哪里,请各位高手指教,多谢!
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