Combine sugar and cinnamon. Arrange tortilla wedges on a baking sheet. Brush both sides of tortilla wedges with butter; sprinkle both sides with the cinnamon-sugar mixture. Broil for 1 minute on each side or until lightly browned. Place the caramel topping in a small microwave-safe bowl, and microwave on high for 45 seconds or until melted. Place 1/2 cup ice cream into each of 6 bowls. Drizzle about 1 tablespoon caramel topping over the ice cream. Serve each sundae with 3 tortilla wedges.