【单选题】
理想集成运放输出电阻为___
A. 10Ω
B. 100Ω
C. OΩ
D. 1KΩ
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答案
C
解析
暂无解析
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固定偏置共射极放大电路,已知RB=300KΩ,RC=4KΩ,Vcc=12V,β=50,则UCEQ为___V 。
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【单选题】
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多级放大电路之间,常用共集电极放大电路,是利用其___特性。
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单相半波可控整流电路电感性负载接续流二极管,α=90°时,输出电压Ud为___
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单相桥式可控整流电路电感性负载带续流二极管时,晶闸管的导通角为___
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下列不属于位置控制线路的是___
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三相异步电动机能耗制动的控制线路至少需要___个按钮。
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三相异步电动机倒拉反接制动时需要___。
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三相异步电动机再生制动时,定子绕组中流过___。
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同步电动机采用变频启动法启动时,转子励磁绕组应该___
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