Buy a new Original Lenovo Power Supply 45 Watt Slim-Tip 0A36262 for T540p T440 X240 X1-Carbon
Amazon.com: Pwr UL Listed CAR Charger 90W 65W for Lenovo ThinkPad X1 Carbon X1 Yoga 1st Gen T Series T470 T470S T460 T450 T440 T570 Laptop Power Supply Cord : Electronics