PlayStation Network cards are virtual funds that act as a substitute for regular credit cards. Sold in $10, $20 and $50 denominations as of March 2011, users can purchase these cards at local stores in order to purchase digital content, such as movies or video games, on the PlayStation Network. When you redeem a card you will notice the full face value of the card is placed inside your PlayStation Wallet menu. These codes are used to redeem the card amount and place a balance onto your PSN account.
Sign into your PSN account. Enter both your user name and password using the PlayStation 3 controller. If your PS3 automatically signs you in, you do not have to re-enter the information.
Highlight the PSN account by scrolling over it. Press "Triangle" and a drop-down menu will appear. Select the "Account management" option. From the account management option, select "Add funds." A keyboard menu will appear.
Locate the 12-digit code on the back of the PSN card. Using the PS3 controller, enter the 12-digit code to redeem and activate the PSN card.