Why do some laptop chargers have three prongs? I get in 2 prongs there is one for positive and one for negative, but why 3? Thanks in advance, sir/ma'am. - Quora
power supply - How do I wire up an aftermarket USB Type-C connector so that it works? - Electrical Engineering Stack Exchange
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HP Laptop Charger 3 Pin-Out Explained and diy 12v charger - YouTube
DTK 120W 19.5V 6.15A Laptop Charger Replacement for HP Notebook Computer PC Power Cord Supply Lead AC Adapter Pavilion ENVY OMEN WASD Connector:4.5 x 3.0mm : Amazon.co.uk: Computers & Accessories
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Where do I connect the positive wire when repairing a laptop power jack? - Quora