An Replacement Apple laptop AC adapter has 3 important components. You should understand these things first before buying the charger. This will help you to choose correct Apple power adapter.
- Output Voltage and milli-Amps
Try and Find your specifications for an Apple ac adapter. On the old adapter, Device wishing to supply or specification page in an owners manual. The specs are usually given as volts and milliAmps (mA). Always try and find a exact match of specs. This is the safest way to go. Where an exact match is not available a couple general rules of thumb to find a workable adapter.
Choose the closest voltage available. Safer to go lower the higher. Some devices can handle higher without damage but many will not take it. If you choose lower generally the worse that would happen is it would not supply adequate voltage and equipment would not normally be damaged.
Choose milliAmps equal or higher than required
- Wattage is another factor on the apple laptop. Watts also called as W. Watts are calculated as Volts multiplied by Amps. So W = V x A. So if your apple laptop requires 19.5V 3.34A then it will be 19.5 x 3.34 = 66.5w. So you will need to buy a 65w charger.
Note that most of the chargers will not exactly provide Watts; you can safely buy the charger as long as Volts and Amps are matching.
A power supply adapter with higher wattage will be advisable for your notebook. For example if your computer has 19.5 and 3.4a then you may consider to buy 65watts adapters. If your laptop needs 4.62a then you must buy a 90watt power cord.
- Last point to consider is connector tip that connects to the computer.Basically, apple battery charger comprise of 2 ends. One end is male power outlet. You use this end to plug into wall power outlet. The other end is called "TIP" which you will plug this tip into the "DC IN" in your laptop. Your laptop won't work on the wrong tip. You can only use the " matching Tips"
