IvanFlex

map = new google.maps.Map(document.getElementById('map_canvas'),mapOptions);


        var allowedBounds = new google.maps.LatLngBounds(
            new google.maps.LatLng(-63.5),
            new google.maps.LatLng(63.5));
            
        google.maps.event.addListener(map, 'dragend', function() {
            var maxY = allowedBounds.getNorthEast().lat();
            var minY = allowedBounds.getSouthWest().lat();
            var x = map.getCenter().lng();
            var y = map.getCenter().lat(); 
            
            if ((y < maxY && y > 0) || (y > minY && y < 0)) {
                return;
            }

            if (y < minY) y = minY;
            if (y > maxY) y = maxY;

            map.setCenter(new google.maps.LatLng(y, x));
        });