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Need help on LDO simulation.

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kumarghz

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ldo simulation

Dear All,
Attached my screen shot of my simple LDO design. Can some one guide me to simulate following parameters, 1. Phase Margin 2. PSR



Thanks.

regards,
Kumar
 

hbk2222

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inurl:viewtopic simulation

u put an iprobe between the opamp and the pass element and use the stability analysis to check the phase margin and for the psr u put 1V Ac on the supply and use ac analysis to get the transfer function from the supply to the output.
 
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kumarghz

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simulate stability of ldo

Dear essawy,
Thanks for reply.

iprobe did you meant a Current probe? how to do stability analysis in SPICE then?

For PSR, that AC signal, is this should be added together with Vsupply? or AC supply alone?

pls advice. thaks

regadrs,
kumar
 

LvW

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pspice ldo phase margin

kumarghz said:
iprobe did you meant a Current probe? how to do stability analysis in SPICE then?
kumar
Which simulator engine do you use ?
If the program does not contain a specific stability analysis package you have to apply the stability definition: Simulate the ac response of the loop gain Lo(w) and determine the phase margin at the frequency where the magnitude Lo=1.
 

hbk2222

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ldo simulations

from this schematic i knew that it is spectre so i told u about spectre,but if the stability analysis isn't found so u can use as LvW said
 

kumarghz

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inurl:2009/4

For your information, I'm using Tanner tools i.e: S-edit & T-spice.

Thanks.
regards,
Kumar
 

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