Hello,

I am getting poor results trying to model noise when using the AD8332 in Orcad PSpice. When looking at input referred noise with a shorted AC coupled input, I am seeing around a 200nV/rtHz noise floor (specs claim as low as .74nV/rtHz). Can Analog confirm or deny that the AD8332 model posted on the web can be used to look at noise for this amplifier? It would seem like given the applications for this amp that noise would be modeled. If it can I will post my schematics and plots to see if anyone can point out what I am doing wrong. Thanks for any info you may have.

Kevin

Hi Kevin,

It is true that the noise spectral density of the AD8332 LNA is not modeled properly in SPICE. The AD8332 is done in a bipolar process, so the 1/f corner is low enough that it is not in the region of usable bandwidth after AC coupling above 100kHz. The noise spectral density of the part can therefore be thought of as a flat value of 0.8 nV/rtHz up to the bandwidth of the part.

Regards,

Paul