Electronic – Modifying an op amp filter to use single supply

active-filterband passltspiceoperational-amplifier

I'm having much difficulty modifying a "state variable" bandpass filter from being dual supply to single supply. (https://www.electronics-tutorials.ws/filter/state-variable-filter.html)

Here is what the circuit and frequency response should look like, screenshot from the website. I am only concerned about the bandpass filter response.
enter image description here

The following LTSpice simulation is done with dual supply rails and matches the expected graph:
enter image description here

But when I try changing the supply rails to what I think would work, I don't get much of anything at the output. I've tried variations on this but all them end up being down in the -50dB to -60dB range.
What I've done is simply change all the negative rails over to ground, then changed the (+) terminals of the op amps to a bias voltage at half-rail (2.5V).
enter image description here

I'm not quite sure what's going wrong, and have been stuck for some time.
Any help appreciated.

Edit:
In response to the comment below, here is what you get when you change the AC source ground to vbias. Adding or removing the cap between V2 and R1 doesn't change much, adding or removing the 1M resistor also doesn't change much.
enter image description here

Update with answer:
I picked an op amp at "random" in LTSpice's menu. Changing the type and adding the cap between the source and R1 fixed the simulation. I breadboarded the circuit below, but am still getting the response above – more debug necessary. But that is a separate issue and this question here is resolved. Here is what I ended up with.
enter image description here
Thanks everyone!

Best Answer

The OP227 op-amp is not designed to work down to a single power rail as low as 5 volts. I'm not saying that some PSPICE models of the device wouldn't come up with the goods at 5 volts though but, you have to be mindful about your expectations. If you look at TPC 27 in the data sheet you'll see that the minimum overall rail voltage is about 7 volts: -

enter image description here

And if you read the data sheet for input voltage range it is typically +/-12.3 volts on +/-15 volt rails. If you did the maths and worked out what the input voltage range is on a single 5 volt rail it would be nonsensical.

A half-decent SPICE model would fall-flat on a single supply of 5 volts (as you would expect). Try running it on a 30 volt rail just to see that it works then, opt for a different op-amp that is 5 volt rail compatible.

And yes, you do need to put a series capacitor on the input unless you bias it appropriately to mid rail.

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