hi,all
i have some questions about psrr in ldo design
1. if there are 3 sub-modules in my ldo , then psrr of ldo depends on the minmum psrr of the sub-module ,is that right ?
2. first i checked my bandgap's psrr. i wanna a psrr of 60db@10k,however ,in my design, only 57db@10k. then i checked the psrr of the opamp used in bandgap.which is 60db@100k and meets my needs. so how can i improve my psrr of bandgap without increase the Ac gain of opamp
anyone could give me some advice ?
suggestions and advice will always be welcome, thx a lot
suppose your psrr is a total combined effect of your circuit. So you don't need to add all the psrr together (they are not noise power). All you have to do is make sure the signal path from supply to you output. Then run AC for psrr.