关于LDO的一些浅显问题

ota不是也是op的一种么，所以都有可能啊，看要求的。
OTA的current drive能力受限
分压电阻可以在里面面也可以在外面，也是看应用。在里面的话用什么电阻要看你用的是什么process阿，一般的poly电阻组织比较小，要做分压电阻的话会很占面积阿，well电阻divation比较大，不好control,用mos匹配度不好，比例容易失调。

看工艺了！如果是用unsalicide poly电阻效果还是很不错的，而且size也是可以接受的。

When you design LDO, Basically you have to know
(1) PMOS or NMOS type Power Transistor
(2) Trimming or not(1% accurate must need trimming)
(3) Programmable Vout or Not, if fixed Vout, so much simple. If need programmability, some case you need external R, Fuse, Register controlled or trimming.
(4)ILoad(Max), Vdrop, PSRR, Noise, Line/Load Regulation, Protection etc.
(5) Process
Based on above, you may come out some the basic architecture, Tune your design via hand calculation and simulation.

Hopefully it helps you.

thanks a lot

Great！
If you still have quesiton, don't hesitate to let me know. Thanks either.

用OTA＋buffer,用ＯＰ都可以吧

perfect answers

我靠，都在放鹰，神呀，救救这些主儿吧！