LTSPICE: When using a single power supply, the AD8041 input bias current is too high.

If you look at the AD8041 model in ADI.lib, you'll find connections of components at the AD8041 inputs (See FrontEnd.asc).  All four capacitors tied to the inputs are spec'ed with parallel resistances.  When +V and -V are at 5 volts, the bias currents come from I1 and I2 and meet typical spec, but when -V=0 the inputs get additional currents flowing out through the parallel resistances connected to +V making the bias currents approx. -16.8uA.

FrontEnd.asc

Thank you very much for your response! I have simulated it and it indeed works as expected. However, I have another question: does the simulation model of the AD8041 differ from the actual device when using a single power supply? Do I have to simulate this op-amp with dual power supplies? Thank you again!

I believe you can still use single supplies but keep your reference at Vs/2. That will help keep the bias currents in spec.  In the AD8041 part spec, notice those TCP scope traces shown center around Vs/2.  The input R/C stage models the Input Characteristic specs.  Checkout figures 9 and 13 of the part spec.  They're good examples of single supply application.

I believe you can still use single supplies but keep your reference at Vs/2. That will help keep the bias currents in spec.  In the AD8041 part spec, notice those TCP scope traces shown center around Vs/2.  The input R/C stage models the Input Characteristic specs.  Checkout figures 9 and 13 of the part spec.  They're good examples of single supply application.

I have understood now, and I've gained a lot from it. Thank you very much for your patient explanation!