给仿制乐林并联3886的朋友泼盆冷水

yh15151515 · 发表于 2019-5-30 17:02

那些卖家确实没有真的去仿乐林的电路图，网上3886并联有2种版本，一种是官方的运放调零并联方案，一种是国外http://www.shine7.com的BPA300方案，其实这个电路只是参考乐林调零思路做的直流偏移量(这个是无法调零的，但是可以调到一个固定的直流偏移电压)调整电路，然后组成BTL后，输出为0电平，真的乐林电路是在3886负端通过电位器调整正负电压直流偏移进行调零.
理解下面这段话就知道了。
I used the LM3886 in the inverted configuration, the reason is that I can use a trim pot to adjust the DC offset of each 3886. National's application note AN1192 suggested to use servo to set the DC offset to zero, but I prefer this simpler solution. After some adjustment, I can get the DC offset of each 3886 to about 9mV, because this is a push pull configuration, the DC offset at speaker terminal would be very close to 0mV.