If the proper charging document ( called an "Information" ) has been filed by the State attorney, you could potentially be held in custody until the trial, should you not be able to post the bond set in your case. If the charging document is not filed, there are specific deadlines which must be met or else you may be eligible for release without bond. You need to seek the advice of an experienced defense attorney in your area to examine the circumstances of your case and what your options are...good luck
Mr. Heyman is correct. There is a rule saying your are entitled to a hearing for probable cause within 24 hours and you will usually be held afterwards as PC is likely present, at least in the eyes of the judge. Then you must have a bond hearing where release bond is set. If you can afford it, you can bond out. If not, they will hold you.
If no information is filed, they have up to 40 days to file charges or you should be eligible for release with out bond. Once they do file the information, they can hold you up to your trial or plea.
Speak to an attorney in your area before turning yourself in or call the Public Defender and see if they have any information for you. If possible, try to arrange a bond before going in so you can get back out while you defend your case.