Why does 4ma flow between the + and - supply in this spice simulation? I could not find anything in the data sheets that talks about this. Is this normal in circuits?

Thanks

 

Yeah, check out Icc: 4mA typical.

As to why it is negative, where are you placing the virtual ammeter? If you measure across the supply, it will read -4mA; however, if you measure at the positive 'pin' of the schematic it will read +4mA.

 

Unrelated to supply current, but you need a ground return for your signal source. It does not necessarily need to be tied directly to ground, but there needs to be a current path.
I'm also curious why you have 1k resistance in your power supply.
The absolute maximum supply voltage on the LT1720 is 7 volts (you are using 15). Is that because you were experimenting with the supply current?