SSL certificates do not require a dedicated IP address. However, that is half the equation. The other end is you need to figure out your intended SSL enabled site’s visitor traffic profile to see whether or not your visitor’s web browser and OS support SNI - which allows SSL certificates to share a single IP.
WinXP doesn’t support SNI. You can check global browser SNI support via http://caniuse.com/#search=SNI
So use your Google Analytics and break down your visitor profile stats for example one of my sites GA stats where ~1.669% of my visitors use WinXP and do not support SNI. If your visitor browser profile breakdown has a high percentage of WinXP users as some Asian countries do, then you may want a dedicated IP for SSL certificate 
