关于LDO调整管的选择

jieling111 · 发表于 2011-9-7 07:41:25

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在CMOS工艺中，可以选择NMOS和PMOS作为LDO的调整管
那么这两种类型的device在应用时各有什么优缺点呢

jieling111 · 发表于 2011-9-7 07:42:41

除了NMOS的压差比PMOS的大之外
谢谢各位了

helianalog · 发表于 2011-9-7 08:37:07

http://bbs.eetop.cn/viewthread.p ... Borderby%3Ddateline

看看这本书的第42页，应该有你需要的答案。

jieling111 · 发表于 2011-9-7 13:27:51

谢谢啦,书里的确讲的很清楚

jieling111 · 发表于 2011-9-7 13:54:35

看看这本书的第42页，应该有你需要的答案。
helianalog 发表于 2011-9-7 08:37

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针对这本书里讲的内容,我好有一些疑问,能否给我讲一下?
书中43页提到:
Load transient. NMOS HDO enjoys better AC line regulation due to better
                     PSR. DC line regulation of a regulator depends on the DC open-loop gain,
                     which is often sufficient in design (≥ 60dB) regardless of the pass element type.
                     NMOS HDO is also superior in load regulation because of the source follower
                     configuration, which has a smaller RS (1/(gm,N +gmb,N)) before and after closeloop
                     feedback. Therefore, NMOS HDO regulator would experience less voltage
                     undershot and overshot during abrupt load current changes.
为什么NMOS HDO有一个小的RS,它的负载调整率就比PMOS LDO好?
期待helianalog 答疑