promach
Advanced Member level 3
PSRR is inversely proportional to output impedance of LDO.
But Iout_max of LDO is proportional to width of output mosfet (M20) , Rds of M20 is inversely proportional to width of M20.
Given that output impedance is a parallel impedance configuration between Rds of M20 and (R1+R2), so Iout_max is proportional to output impedance of LDO.
If I need Iout_max = 3A, then my PSRR result looks very very bad.
But Iout_max of LDO is proportional to width of output mosfet (M20) , Rds of M20 is inversely proportional to width of M20.
Given that output impedance is a parallel impedance configuration between Rds of M20 and (R1+R2), so Iout_max is proportional to output impedance of LDO.
If I need Iout_max = 3A, then my PSRR result looks very very bad.
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