电容的漏电流问题

思海

AB类功率放大器前面的耦合电容有漏电流导致功放输出有直流成分，请问什么电容的漏电流控制得比较好，电解电容、陶瓷电容、钽电容各种电容的漏电流如何。除了精选电容，还有什么方法减少漏电或者减少输出的直流成分。
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超級狗

. V8 f$ ^" @* ^& r% `0 K+ x節錄自踢哀（TI）官網
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http://www.ti.com/product/TPA0211/datasheet/application-and-implementation
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! j7 o& q  x9 \9 t0 d0 c* j' k4 REquation 12.
6 f/ ]  t) T2 O, u& x4 hIn this example, Ci is 0.4 μF so one would likely choose a value in the range of 0.47 μF to 1 μF. A further consideration for this capacitor is the leakage path from the input source through the input network (Ci) and the feedback network to the load. This leakage current creates a dc offset voltage at the input to the amplifier that reduces useful headroom, especially in high gain applications. For this reason a low-leakage tantalum or ceramic capacitor is the best choice. When polarized capacitors are used, the positive side of the capacitor should face the amplifier input in most applications as the dc level there is held at VDD/2, which is likely higher than the source dc level. Note that it is important to confirm the capacitor polarity in the application.
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