After a laptop is discarded, often its power adapter is still intact. However, because they have become useless, most people don't keep them any more. We made some modifications to the adapter, so that it will have multiple USB outlets for mobile phones, mobile power bank, tablet PCs and other devices to charge. USB outlets on laptops usually have enough power to supply up to 8 mobile devices simultaneously. Thus, laptop power adaptors could be re-used in our daily life to continue to serve. In this way, we can reach the goal of re-using wasted electronic products.
Step 1: Material preparation
(1) laptop power adapter, advertised power of 90W, output voltage 19V
(2) 8 sets of voltage converter modules
(3) plexiglass plate
(4) copper pillars/studs, screws, pieces of wire, etc.
Step 2: Boards Assembly
First connect all the power converter boards to a 19V power supply.This is to check whether all the boards' functions are intact. Then bolt the boards together with copper pillars in between. Then organize all the wiring.
Cut up the wire of the DC end of the laptop power adapter. Connect the positive and negative ends of the wires to the corresponding poles of the converter boards. Cover the contact points with insulation duck tape.
Step 3: Casing Assembly
First drill four holes on each side panel of the casing to attach the copper pillar. Place the power adapter underneath the converter boards and tie the power adapter to the bottom panel. Bolt four rubber stands to the bottom panel.
Organize the wiring and then hold the side panels in place, glue them with glass adhesive. Then place the cover on top.
Step 4: Test
Plug in the power cord, check if the converter boards' status light is on. Then use multimeter to check the voltage of each USB outlet, if the output voltage is 5V, then try to connect phones and tablets to the USB. At this point, these devices should be properly powered.