Rebuild 2005

"By the way, there is one more thing."

After the meeting ended, Wei Qingfan was about to leave when Xiao Jiasheng suddenly said, "About the fast charging plan for mobile phones."

Wei Qingfan sat down again, motioned for others to leave, and asked, "What's wrong?"

On the basis of Wei Qingfan's low voltage and high current direction, the company's first-generation fast charging solution adopts a 5V*2A solution, and is currently conducting safety verification and improvement in conjunction with the Jiangjiu 2 engineering machine. Alternatives are under development.

"The research and development team proposed a new plan."

Xiao Jiasheng explained, "They speculate that the fast charging of mobile phones, the voltage is about 10V, is the bottleneck, and the current is about 5A, it should also be the bottleneck. In this case, they assume that we will reach the fast charging power of 50W in a few years. .

"Because Mr. Wei asked the follow-up fast charging solution to be compatible with the previous generation, they reversed several solutions. From the perspective of compatibility, the second generation will increase the voltage better, so after the original 5V*3A 15W solution In addition, a 9V2A 18W solution was proposed..."

Because of worrying about the situation after the rebirth cheat disappears, Wei Qingfan has been trying his best to avoid the situation of overthrowing the seedlings. For this reason, he even consciously exchanged his "majesty" for everyone's enthusiasm and encouraged different voices.

Therefore, in the fast charging plan, although he gave the direction of low voltage and high current, he has been emphasizing that other ideas can be put forward.

Different mobile phone manufacturers have a long history of developing different charging protocols. For safety considerations and to have a minimum charging standard when the protocols do not match, the USB Alliance has long stipulated standards. The USB2.0 protocol specifies a standard voltage of 5V, The maximum current is 0.5A, and the total power is 2.5W.

In the era of smart phones, the charging power is too slow, and the standard USB interface is used in smart phones, so the USB Association supplemented the BC2010 charging protocol in October 10, increasing the maximum current to 1.2A , the power has been increased to 1.5W.

Subsequent charging protocols of different versions are basically developed on this basis.

At this time, all smartphones use the Micro USB interface. There are 5 pins in this interface, and only one pin is used for charging. The highest safe current of this pin is 2A.

Wei Qingfan already knows these things, and he also knows that Qualcomm will soon propose a 9V*2A 18W fast charging solution, but he also knows that the Type-C interface will come in mid-2013, and a breakthrough will be possible at that time The Micro USB interface is limited, but there is no way to say it.

He originally proposed a low-voltage solution. On the one hand, he wanted to implement the 5V*2A solution as soon as possible;

At the beginning, OPPO R7's phrase "charging for 5 minutes, talking for two hours" was realized through the magically modified Micro USB interface, which achieved 5W fast charging of 4V*20A.

另一个方向，则是当时的华为，在迅速改换了Type-C接口之后，于2016年的MATE9上通过4.5V*5A方案同样达到了22.5W的充电方案，随后在2018年又拿出了10V*4A的40W超级快充方案。

Everyone has switched to the Type-C interface, especially after the emergence of charge pump technology, high-voltage and high-current solutions have become mainstream, and the fast charging power has developed to 100W, 120W or even higher, but the mainstream is still 50W, Near 60w, the slight difference is just a promotional caliber, and the real charging power is even lower, and most of them are "five-second real men", which means that the power will be lowered at once.

After hearing Xiao Jiasheng's speech, Wei Qingfan asked, "If you use 9V voltage, what about the safety?"

The general lithium battery used today has a standard voltage of 3.7V and a fully charged voltage of 4.5V. Many people claim that the 5V voltage is actually not available at all, and the 9V solution is two standard voltages.

Xiao Jiasheng will propose this plan, and the R&D team naturally already has an idea, and immediately replied: "Use inductors to adjust..."

Wei Qingfan immediately realized that this is basically the idea of ​​Qualcomm's 18W fast charging solution, which is also adjusted by "inductors". Simplified and simplified, it is adjusted by using the characteristics of inductors that do not allow sudden changes in current to ensure safety.

This principle is just "coupled" with the principle of the later "charge pump". The core of the charge pump is a capacitor, and the characteristic of the capacitor is that it does not allow sudden changes in voltage.

Wei Qingfan felt like being backstabbed by high school physics knowledge, patted his head, thought for a while and said: "Then develop first, develop both sides..."

"it is good."

Xiao Jiasheng nodded in agreement. Although he knew that Wei Qingfan would probably give such an answer, he was relieved to hear it.

Even if things like "disobedience" to the boss have happened several times before, it doesn't mean that the next time will be safe and smooth.

According to this idea, after switching to the C port, there is a high probability that the charging power can reach more than 20W. Then you have to get a low-profile version of the C port, both 18W and 10W, and distribute it to other models.

But this one is simpler.

With this episode resolved, Mr. Wei was finally able to return to his office. When he passed by Jiang Qinghuai's office, he saw no one at her desk, so he went back to his office. Sure enough, he saw Secretary Jiang tidying up in his office. Two stacks of papers.

"so much?"

Wei Qingfan was a little depressed, "How many things are there?"

"Half a month, what do you think?"

Jiang Qinghuai was cleaning the cupboard for him, wiping the collected mobile phones and the books placed one by one, and then carefully put them back to their original places, "The stack outside is for reading, and the stack inside is for signing... you sign slowly Bar."

"Okay, follow orders..."

Wei Qingfan sighed, sat down at the desk, but didn't remember to work, first took out his mobile phone, and checked his unread messages.

The content of the work was directly filtered by him, let's look at the two women first.

Li Miaoyu: "I'm done!"

Li Miaoyu: "Where shall we eat at night?"

Wei Qingfan took a picture of the document on the table, sent it to her, and typed:
"Boss Wei is still working hard."

"You just decide, I believe in Miaomiao's taste."

Look at Li Wanyi's post again: "Miaomiao is going to have dinner tonight, you can ask Jiang Qinghuai to come with you."

Wei Qingfan: "Why is my name?"

Wei Qingfan: "I want to call you."

Li Wanyi: "Then stop barking."

Wei Qingfan: "???"

Wei Qingfan: "It's so boring not to call, let's call."

Wei Qingfan: "Your name."

Li Wanyi: "Then let Miaomiao call."

Wei Qingfan: "That's fine, either of you can be called."

After sending it, Li Miaoyu also replied:

"I'm already home, you just reply to the message."

"Then you should work hard and earn money."

Wei Qingfan: "Got it, make money to support your family, and you can't let down my Miaomiao's beauty."

Lai Miaoyu: "It kinda rhymes, very self-conscious."

Li Miaoyu: "I'll pick you up in a car later, okay?"

Wei Qingfan: "No, I dare not."

Wei Qingfan: "Do you dare to go out on your own?"

Li Miaoyu: "Don't dare, but it's not too far to go to your company, and I'll go now, there are few cars."

Wei Qingfan: "Now there are a lot of cars."

Wei Qingfan: "But it's okay, you can also drive over, just slow down, it's okay to crash, don't hurt anyone."

Wei Qingfan: "It's a pity that you had to change to a BMW at that time, otherwise you should have bought a more expensive one, so that others would not dare to bump into it easily."

Li Miaoyu: "The BMW 750 is also very expensive. Do you really think that in Beijing, the streets are full of million-dollar luxury cars?"

Li Miaoyu: "And I drive well, why did you hit me?"

Wei Qingfan: "Just in case, just in case."

Li Miaoyu: "Also, why did you ask me to call Qingqing again? Turning around, my sister scolded me again."

Wei Qingfan: "Why did I scold you?"

Li Miaoyu: "She's a bad woman, you don't need a reason to scold me."

Li Miaoyu: "The last time I told Qingqing about the Dousse Wildlife Park, she scolded me."

Wei Qingfan was a little amused, and typed and asked, "What are you scolding?"

Li Miaoyu: "It's too much to say that I have rebellious bones in the back of my head, and my head can't control the rebellious bones!"

Wei Qingfan: "Hahahahaha"

Wei Qingfan: "Then don't talk about it next time."

Wei Qingfan: "But it's okay to shout for dinner, everyone is used to it."

Li Miao said: "Then I won't shout, I will call you."

Wei Qingfan: "It's okay, just call me."

Li Miao said: "No."

Wei Qingfan: "If I call, I'm afraid Jiang Qinghuai will misunderstand."

Li Miaoyu: "It also makes sense."

Li Miaoyu: "Okay then, let me call."

"why are you laughing?"

After Jiang Qinghuai cleaned up, he saw Wei Qingfan holding the phone and laughing, he couldn't help but wondered, and curled his lips, "And he smiled so obscenely."

"Who is obscene?"

Wei Qingfan retorted dissatisfiedly, and laughed again: "Miaomiao said to have dinner together at night, let me call you, and I'll let her call you."

"That's it?"

Jiang Qinghuai was quite used to parties, so he didn't think it was funny, and Wei Qingfan didn't look happy either.

"Is this not good?"

Wei Qingfan put down her phone and got up, stretched her waist, saw that the office door was closed, she took off her coat, and wore a light brown knitted sweater, which outlined a slender waist and faintly undulating curves. Walked over and said, "Let me hug~"

"no!"

Jiang Qinghuai was startled, and quickly hid to the side, fearing that he might misunderstand, explained in a shy voice, "If you start this way, you will definitely do this often in the future... You can't do it in the office, okay?"

"Nonsense, am I that kind of person?"

Wei Qingfan didn't force it, but retorted unconvinced, "I've always been very restrained, okay?"

"I don't believe it."

Jiang Qinghuai blushed and annoyed him, and didn't have the nerve to say anything later, because since the kiss that day, Wei Qingfan took the opportunity to kiss frequently, and the kiss made her shy and happy, flustered and enjoyable.

Once I let him kiss in the office, it is entirely conceivable that this kind of thing will become the norm when I am alone in the office in the future.

"Well, everything is difficult at the beginning."

Wei Qingfan didn't force her either. Anyway, she has kissed many times these days, so let her get used to it first. In the future, intimacy in the office will become the norm, so it's better not to overdo it.

Moreover, now that he has returned to China, there are senior sisters and Miaomiao tonight, so he can suppress his restlessness first.

Seeing that he was honest, Jiang Qinghuai was a little worried that he was unhappy and would think too much. When he was struggling, the mobile phone next to him rang, so he picked it up to look at it, and then typed a reply.

Wei Qingfan asked: "Miaomiao?"

"Ah."

Jiang Qinghuai nodded, and said, "Then I'll call Zhou Li and Feng Yongan...You can call Feng Yongan."

"it is good."

Wei Qingfan sent Feng Yongan a message, and he replied quickly: "I'm afraid not, I have to work overtime at night."

Wei Qingfan: "It doesn't matter, go to eat first, you finish eating quickly, just come back and work overtime after eating."

Feng Yongan: "???"

Feng Yongan: "I thought you would say that you won't work overtime tonight."

Wei Qingfan: "How can that work?"

Wei Qingfan: "You can't go to the company's business just because I treat you to dinner. Isn't that abolishing public affairs for personal reasons?"

Feng Yongan: "[Like]"

Feng Yongan: "Boss Wei is really selfless!"

Wei Qingfan: "You are polite, you are polite, you should."

Feng Yongan: "You're welcome, you're welcome, I deserve it."

Wei Qingfan ignored his complaints, put down his phone, and said to Jiang Qinghuai, "I've made an agreement with Feng Yongan."

"what?"

Jiang Qinghuai was a little surprised, "Isn't he working overtime today?"

Wei Qingfan smiled and said, "Plus, but he said that he can eat first, and then come to work overtime after eating, and there will be no delay on both sides."

“Great staff~”

Jiang Qinghuai clicked his tongue twice, then shook his head, praised sincerely, and then added: "What a good boss!"