推 waniac:我想Cde正比穿越時間 所以應該是增加 10/03 22:56
→ waniac:fT=gm/Cde+Cje+Cu , Cde增加 fT減少 10/03 22:59
→ K7788:Cde增加 gm也會增加 10/03 23:18
推 alen77129:B一定是錯的 Cde=基極穿越時間*gm 基極穿越時間是 10/04 23:59
推 alen77129:wb^2/2*Dn 10/05 00:05
Consider the emitter diffusion capacitance Cde of a BJT.
Which of the following statements is correct?
(a)If the emitter current increase , Cde decrease.
(b)If the base width increase,Cde decrease.
(c)The large the value of Cde,the smaller the unity-gain frequency fT.
(d)If the BJT is operated in the active region,Cde is smaller than the
collector junction capacitance.
答案是給C
不過我是覺得B
有大大可以幫忙解惑嗎?
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