Will a high-power charger damage your mobile phone?

Tiktok recently saw what I saw in a loud voice on the jitter. I couldn't remember the title clearly, but the video content was basically: shaking the phone with 87W charger to charge the mobile phone, and testing what would happen. In fact, the content of the video did not attract me, but the comment area made me feel a little surprised.

Why? Because there is a question raised by netizens in the comment area, which makes me very deep.

"87W, isn't this a laptop charger? With such a large amount of power, can't the mobile phone be charged

Why? It's 9102 years old. Are you worried that the charger will damage the mobile phone? Xiao Bian turned over the comment area and found that there are still quite a lot of people concerned about this issue.

So, will the high-power charger charge the mobile phone?

Before answering this question, we need to understand the charger output interface type and its working mode.

1、 Charger output interface and working mode

At present, the output interface of chargers on the market can be roughly divided into two types, one is usb-a, the other is usb-c. At present, the most common is usb-a interface. This interface has been used for more than 20 years. We can still see it in many electronic and digital products, and usb-a interface products are constantly available in the market. To use an idiom to describe it, "old and strong" is more suitable.

The shape of usb-a interface is rectangular. Most people's first contact should be in the back of the computer case, at least in the post-90s and before. In addition to the shape of the outer body, its most obvious feature is the four metal shrapnel (contacts), two of which are responsible for power transmission (positive VCC and ground GND), and the other two are responsible for data transmission (data positive D + and data negative D -).

In the fast charging charger with usb-a output, the D + and D-signal lines are responsible for transmitting the voltage signal that changes according to a certain rule, and they are mutual "code" with the mobile phone. When the code is matched, the charger will output high voltage or large current (when the output current exceeds 3A, the mobile phone will also detect the line group of the charging line). Otherwise, the default is d + and d-short circuit, the protocol is DCP, and the output voltage is 5V / 1.5A.

The picture above shows the change curve of Xiaobian when charging Xiaomi 9 with QC charger by using chargerlab power-z km001 tester. The green curve is the change curve of D + voltage of usb-a port of charger, and the orange curve is the change curve of D-Voltage.

After charging for about 4 seconds, when Xiaomi 9 is connected to the charger, the charger changes the voltage value of D +, D -, and Xiaomi 9 detects the change of the voltage value of D +, D -, which is in line with the characteristics of QC fast charging voltage. After the code is on, the voltage and current of the charger begin to rise, and enter the QC fast charging, just like the secret agent's "code", only when the "code" is right can you get something.

In addition to using D +, D - "code" to judge the protocol, there are also some fast charging protocols that use current pulse signal to check the code, such as the PE fast charging protocol of MediaTek. Xiaobian uses chargerlab power-z km001 tester to monitor the change curve of PE charger charging Meizu 16th plus. When charging the 16th plus of Meizu, there is no current all of a sudden. This is the current pulse signal sent to the 16th plus of Meizu (the position of the red circle in the picture). It is a bit like "Morse code". Meizu 16th plus receives these pulse signals and signs with the charger, then the voltage and current begin to rise and enter the PE fast charging.

As for usb-c interface, its shape is similar to a flat oval and its volume is smaller than that of usb-a, but its internal contact is as high as 24pin, which is six times of that of ordinary usb-a interface. More contacts means more powerful functions, which is also true. Usb-c is much more powerful than usb-a in both power transmission and data transmission. At present, more and more devices adopt usb-c interface, which is the future development trend.

In the usb-c charger (PD fast charging), the signal is transmitted through the CC line. The charger and the mobile phone will "talk" with each other to exchange information. The charger will first tell the mobile phone its own power supply information, and the mobile phone will apply for a voltage and current that it can accept. If there is no suitable voltage range, 5V charging or no charging will be selected by default. It's like this.

PD charger: I have five power supply gears.

Mobile: Yes, I want 5V / 3A power supply.

PD charger: got it. No problem. I'll give you 5V / 3A power right away.

Mobile: OK.

PD charger: the power supply gear has been adjusted to 5V / 3a.

Mobile: OK, I have received it. Now I want 9V / 3A power supply.

PD charger: got it. No problem. I'll give you 9V / 3A power right away.

Mobile: OK.

PD charger: the power supply gear has been adjusted to 9V / 3a.

Mobile: OK, I have received it. Please keep it.

The following Xiaobian takes two common high-power chargers Huawei 40W and apple 87W as examples to test for you to see if they are "high-power chargers will not damage mobile phones" as Xiaobian said.

2、 The actual test shows that Huawei 40W charger is a charger with usb-a interface, which supports 40W SCP fast charging, QC fast charging and FCP fast charging.

First of all, we use it to charge the iPhone XS. IPhone XS mobile phone supports PD fast charging and apple 2.4a protocol. When it is charged with the charger, it will first ask whether the charger has apple2.4 charging protocol through D + and D-Voltage changes. If there is no apple2.4a protocol, it will see whether the charger supports dcp1.5a mode (D + D-direct connection). If there is no identification, it can only charge with ancestral Wufu Yian 5V / 1a (0.96a). As can be seen from the figure, when Huawei 40W charger charges iPhone XS, the power is about 5W. In the process of charging, the mobile phone is not damaged due to the "high power" of the charger.

Let's take a look at the more powerful apple 87W charger charging the iPhone XS. Apple 87W charger its charger interface is usb-c, before we learned that usb-c has more contacts than usb-a, the number of contacts is more intelligent.

 

iPhone 12 charger
Apple 87W charger supports USB PD fast charging. When it charges the iPhone XS, they will tell each other their power supply and charging information, just like two people introducing themselves to each other. As can be seen from the figure, the power of the current iPhone XS is 18.99w, which belongs to the safe power range of the mobile phone. The iPhone XS is not damaged because the charger is as high as 87W.

Maybe someone else will say: all you tested are apple phones. What about Android phones?

Android phones are actually the same. Here Xiaobian takes Xiaomi 8 as an example. Xiaomi 8 supports PD fast charging and QC fast charging. Huawei 40W and apple 87W are still used as chargers. Because PD fast charging exchanges information through CC core communication, the usb-a interface does not have CC core, so it does not have CC communication function. When Xiaomi 8 and the charger are powered up, it will skip PD communication and directly ask whether the charger has QC fast charging protocol through D + and D-Voltage changes. If not, it will immediately ask whether there is DCP protocol, and so on.
Apple Charger Cable
Huawei's charger supports QC fast charging. In the figure above, we can see that the current charging power of Xiaomi 8 is 12.77w, which belongs to the safe power range of the mobile phone, and the mobile phone is in normal charging state. Moreover, most mobile phones have a certain high-voltage protection mechanism. When the input voltage, current and power are too large, they will automatically turn off the power and refuse to charge for self-protection. The picture above shows that the PD charger charges the Meizu mobile phone at different voltage levels. Pay attention to the marking ruler in the power-z tester display and the charging status in the upper right corner of the mobile phone screen. It can be seen that 5V, 9V and 12V can be charged normally. 15V and 20V mobile phones will detect that the voltage is too high and refuse to charge to protect the mobile phone from being damaged. Of course, each mobile phone's high voltage range of self-protection is different, we should not easily imitate, it may cause damage to the mobile phone.

3、 Summary of charging head network

Will a high-power charger damage your mobile phone? The answer is: No. Because when the charger is charging the mobile phone, they will have a series of communication and exchange, and can adjust the voltage and current at any time. For the charger with usb-a interface to charge the mobile phone, the two will report "connector code" respectively. If it matches, the mobile phone will be charged. If it does not match, the mobile phone will refuse to charge; When charging with usb-c charger, the communication between mobile phone and charger will be more frequent and accurate, so as to ensure the best charging scheme.

The power parameter of the charger is one of its performance indicators, which indicates how much output power the charger can achieve.

With a simple and easy to understand example, the charger is a car, and the output power of the charger is how fast the car can drive (200 km / h). The mobile phone is like the driver, he controls the gas pedal of the car.

How fast a car drives depends on the driver's needs. You can drive slowly to buy vegetables. You can go on a high speed of 120 kilometers per hour. The output power of charger also depends on the mobile phone. The output power of charger depends on the demand of mobile phone.

So, don't worry that a high-power charger will damage your mobile phone.

However, don't randomly use some exotic chargers, or 48V, 72V power adapters that don't charge mobile phones, or even stab the mobile phone with 220V directly. This will definitely be broken. We must pay more attention to it.