i turn my tv on and stays on for 15 minutes then cuts off. ?

When i turn my tv on, it only stays on for about 15 minutes then cuts off. I turn it back on and it only stays on for a minute or so.

Is it over heating? Can this be fixed inexpensively? The tv is a small 15 inch flat screen. I can purchase a new one for about $200.00, so it may not be worth my time or money to repair.