c*******l 发帖数: 4801 | 1 一直不是很理解,为什么G>1, phase =-180,还不震荡。。。 | C*******g 发帖数: 82 | 2 Maybe the simulator can not faithfully represent the real condition.
【在 c*******l 的大作中提到】 : 一直不是很理解,为什么G>1, phase =-180,还不震荡。。。
| c********r 发帖数: 172 | 3 what kind of simulation did you do? ac-simulation or transient simulation?
Normally in analog design, we don't trust the result of ac-simulation
because the model may not be accurate. We are more reliable on transient
simulation result.
Meanwhile, open-loop-gain>1 is not necessary for oscillating. You have to
check the close-loop-gain (with the influence of parasitic cap in your input
stage). You can do it like this: add a 10G inductance to break the ac-loop
of feedback, and add a 10G cap to bre | T******n 发帖数: 3180 | 4 你是原来贴NCSU找工作那位?
input
loop
【在 c********r 的大作中提到】 : what kind of simulation did you do? ac-simulation or transient simulation? : Normally in analog design, we don't trust the result of ac-simulation : because the model may not be accurate. We are more reliable on transient : simulation result. : Meanwhile, open-loop-gain>1 is not necessary for oscillating. You have to : check the close-loop-gain (with the influence of parasitic cap in your input : stage). You can do it like this: add a 10G inductance to break the ac-loop : of feedback, and add a 10G cap to bre
| c********r 发帖数: 172 | 5 No, not me, but I know that person, I taught him a lot.
你是原来贴NCSU找工作那位? |
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