Revealing: Does the ipad charger really blow up the iphone

Can't the ipad charger and iphone be mixed? Can really cause the iphone to fire? Charging the iphone with an ipad charger is safe, and the cause of the iphone fire should be related to issues such as short-circuiting, which should not be blamed for using the ipad's charger. The IPhone, ipod uses a 5V (Volt), 1A (AMP) charger, the ipad is the original 5V, 2.1A charger, according to the Power = voltage x Current formula calculation, Two charger power on the 5W (Watt) and 10.2W respectively, see this, many friends will take for granted the conclusion: the power difference so much, in exchange for the use of certain danger! But this is not the case, because the iphone and ipad chargers are not a simple combination of voltage and current, but there are many mechanisms. First of all, the charger is not always in accordance with its nominal current size, the actual output current depends on the load (that is, the charging device): If the load current is less than the maximum current charger, the actual current reduced to load current size; If the load current is greater than the maximum current of the charger, The actual current is limited to the charger nominal current. That is to say, the device and the charger whose current is low, the actual current listens to whose. To put it bluntly, the iphone's maximum charging current is 1 A, and even if the ipad charger is any bigger, it will have to accommodate the iphone, lowering the current from nominal 2.1A to 1 A, without a single piece of the iphone being blown up. From this perspective, we can come up with a variety of combinations: iphone+ipad charger = normal charge (current stays on the upper limit of 1 a); Ipad+iphone charger = slow charge (maximum current only 1 a); (no device) + charger = no power consumption (load current is 0). This principle explains why the ipad charger does not cause the iphone to go bad: Because the current is the size of the lower-endurance side, not the charger. Just like eating a bowl of rice, the fat man will not eat too little because of the meal, and the skinny man doesn't have to push himself to eat all the rice. By the way, the Macbook air and pro charger are the same principle, so mixing is no problem at all. After the rumor, let's see why the Charger for Apple products can automatically adjust the output current according to the load. Careful observation of the Charger's friends know that the USB interface has four pins, the four pins correspond to 5V power supply, d+ (data positive signal), d (data negative signal) and GND (grounding). General charger because it does not require data transfer, so the d+ and D-Two pins are vacant, and Apple in order to allow the ipad charger and other devices to GM, d+ and D-defined respectively 2.7V and 2V voltage (the iphone charger d+ and D-are 2V), If the connection device is an iphone or ipod, the device will identify the charger via d+ and D-Existing voltage difference, which willThe current adjusts to the iphone's ability to withstand 1 a. Conversely, if the ipad is recharged with an iphone charger, the ipad will recognise d+ and D-all 2V, indicating that it is now connected to the iphone charger, that the current will be limited to 1 A, that the charger will not overload, and that the charging time will theoretically be 2.1 times times the same. With this technology, Apple can do multiple devices sharing chargers, reducing the cost of user identification and purchase. If you are still not sure, go to the Apple Online store to check the charger for the device list. Not that the ipad can be recharged for the iphone, and vice versa? A: The reverse is no problem, the actual output current of the charger will be lower than the actual demand of the ipad, so the charging time will be prolonged, but will not create security problems. On the premise of unified charger interface, is the input and output of the charger unified? A: It's theoretically unified, but it's important to note that the ipad's battery capacity is much higher than the iphone, and if you charge with the same current, charging will become a very slow process, which is unacceptable to friends who often use the ipad.