Given the AC is running, radio is on, and the headlights are on.... 15 minutes of actual driving is recommended to replenish the used current. 10 minutes if you keep some accessories off for the wait. Assuming you're not driving at higher speeds just drive for 6-8 miles and you should be good to go.
Edit: Headlights and AC are the first thing we ask someone to turn on if a suspected alternator needs to be tested. The actual load of both AC and Headlights are about equal, but on average turning both on dips roughly 1.5v off the alternator. And if it's a weaker (dying) or bad (dead) alternator it will no longer charge the battery with these on. Radio is only a major factor in the case of aftermarket setups which could take several tens to hundreds of watts to operate. A stock radio won't do anything as compared to the AC and Headlights.