AD8031 PSRR Simulation in LTspice

Question

Hi, 
 for my next course about PSRR, I try to simulate the AD8031 PSRR with LTspice. 
 The used schematic is : 
 
 Result is : 
 
 This is very different from the datasheet graph (i.e. figure 35). 
 How explain that ? 
 Best regards. Eric PERONNIN

gdsalas · Accepted Answer

Hi Eric, 
 Since you are using single supply, add a DC offset in the non-inverting input to use the whole range of input common-mode voltage range. Below is the PSRR graph obtained when I add 2.5V in non-inverting input. It resembles Figure 35 in the data sheet. Simulations are dependent on the part modeling and may present some limitations thus the low accuracy in the low frequencies.

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AD8031 PSRR Simulation in LTspice

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