No, you cannot borrow funds from your IRA or IRA LLC. An extension of credit between a disqualified person and an IRA is a prohibited transaction.
There is often some degree of confusion about this because of the process of doing a rollover distribution. An IRA account holder can take a distribution of retirement funds with the intent to rollover the funds to another retirement account within 60 days. Some account holders will take advantage of this fact and treat this 60 day window as a short term loan. This can be quite risky since any funds not deposited back into an appropriate retirement vehicle within 60 days are considered a taxable distribution. There may also be early distribution penalties in addition to the taxes .
Note: Unlike an IRA, a Solo 401k does allow for participant loans.