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UCC3895最低可以工作的频率是多少

CT描述
where CT is in Farads, and RT is in Ohms and tOSC is in
seconds. CT can range from 100pF to 880pF. Please
note that a large CT and a small RT combination will result
in extended fall times on the CT waveform.
RT描述
where RT is in Ohms and IRT is in Amperes. RT can
range from 40k to 120k Soft start charging and discharging
current are also programmed by IRT .
这样最低的频率是
t=(5*120*880/48)+120=11uS
f=90.9K
我想工作在15KHZ是不是不能使用呢?为什么UCC3895不能工作在低频方式?
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lineliu
LV.4
2
2009-02-24 17:23
应该是可以的,我们用到18K,也没按它参数来
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xyx11
LV.6
3
2011-12-07 21:25
@lineliu
应该是可以的,我们用到18K,也没按它参数来

限制 CT 过大的初衷是

1 放电时间长,影响到最低占空比,

2 内部放电管的功耗

如果在低频下,以上两点可能都不是问题。

 

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