Penal Code section 667.5(b) isn't a criminal charge - it's a sentencing enhancement.
If you are convicted of a new felony and have been to state prison within 5 years of the new offense (the time frame is from the day you were discharged from prison until the date of commission of the new felony), they can add an additional year to your sentence under PC 667.5(b). This five year period includes any reason you were in prison - even if it was on a parole violation. It also can go backwards to not only the last time you were in prison, but if you've been in prison more than once, that five year window goes back to the time before, and the time before that, etc., making the DA able to allege multiple 667.5(b) enhancements for a person who's been in prison multiple times and hasn't stayed out for over five years at any given stretch.
The punishment can be stricken by the judge for sentencing purposes, so it is not mandatory that it be imposed.
What you will get depends more on the current charge you face, the facts of the case and your entire record.