Why is the battery life of the mobile phone always insufficient?

Why is the battery life of the mobile phone always insufficient? How much do you know about those strategies for power optimization?

In the design of mobile consumer products, power consumption and battery life are always a big challenge. Taking mobile phones as an example, the larger the battery capacity is, the lower the chip power consumption is, but the battery life of mobile phones does not bring consumers any benefits. for a significantly improved experience. This is mainly due to the addition of new functions of mobile phones, which increases the power consumption of the whole machine, so that the extended battery life of large-capacity batteries and low-power ICs is eaten up by new functions.

Where is the power consumption?

For example, the popular high-refresh screen today, the early mobile phone screen refresh rate was only 60Hz, and now 90Hz and 120Hz are gradually popularized, and users who are not sensitive to the screen refresh rate are now gradually realizing a better visual experience brought by the high refresh rate. A high refresh rate often means a high data rate, which requires more power consumption.

At the same time, the brightness of the screen is getting higher and higher, and the display of early mobile phones is basically invisible in the sun. Thanks to the progress of technology, the brightness of current mobile phones can easily reach 400nit, even approaching 1000nit, and the screen is a big power consumption. In the mode, the high power consumption makes the heat generation serious, and the heat further affects the power consumption. Therefore, when we are outdoors during the day in summer, our mobile phones will feel hotter to the touch.

I am afraid that aside from the CPU and GPU, speakers are also a big power consumer. In order to provide a better audio-visual experience, stereo speakers have been favored by many consumers in the field of mobile phones in recent years. And the sound effect algorithm behind it will increase the power consumption.

In addition, there are various sensors such as cameras, fingerprints, infrared, etc., and everyone grabs power consumption resources from the battery without exception.

The optimization of mobile phone power consumption has always been a topic worthy of in-depth study, and it is also a very difficult topic. It is necessary to understand the software architecture strategy, hardware principle scheme, manufacturing process technology, etc. A relatively high research direction.

How does the software do it?

List the power consumption optimization solutions from top to bottom. The first is software strategy optimization. The easiest direction is to reduce the main frequency. When we use mobile phones every day, we don’t need the mobile phone’s CPU to run at full load, and DDR does not need to be fully powered. According to users Reasonable scheduling of various work tasks in the use environment and reasonable allocation of resources are the most direct strategies to optimize power consumption.

For the screen, although the screen supports high refresh rate, for static display scenes, such as reading, chatting, browsing the web and other scenes, the screen switching is slow, and the frame rate can be reduced at this time. The reasonable configuration of the frame rate can not affect the user experience. Therefore, how to define high and low frame rate scenarios and then reasonably call different display frame rates requires various mobile phone manufacturers to conduct research on user habits and form their own set of control optimization strategies.

I believe most people know that when we are not using the camera, the camera is turned off, and it will not take pictures or record videos (the behavior of QQ browser to start the camera privately will not be discussed here), which is to reduce power consumption. The direct solution, the module that the user does not need to power off or enter the bypass mode to reduce power consumption, further, there are hundreds of IO pins in the mobile phone CPU, and these pins need to be rationalized according to their respective working states. Configuration, when the setting is low, it should be set low, otherwise there may be abnormal power consumption of hundreds of uA or even mA level, which will undoubtedly increase the power consumption of the mobile phone for no reason and reduce the battery life experience.

How does the hardware do it?

For hardware, it seems that there is nothing that can be done on the surface. In fact, it is not. In addition to choosing high-efficiency and low-power hardware implementation solutions, mobile phone manufacturers can also design a reasonable hardware architecture to reduce the performance of mobile phones without affecting performance. Useless power consumption.

For example, reasonable distribution of power, whether it is BUCK, BOOST switching power supply or LDO linear power supply, their efficiency is not static, we need to design a reasonable power supply architecture to allow them to work in efficient conditions to reduce power consumption. Generally speaking, the efficiency of switching power supply is better than that of LDO, so switching power supply can be used preferentially in places that are not sensitive to power supply noise. Reduce power consumption.

At the beginning of 2020, a mobile phone manufacturer launched a mobile phone with a 4 POWER screen. Its promotion point is to improve the battery life experience. There is a power supply in the screen, which is from 1.8V to 1.2V. If it is powered by a linear power supply, the efficiency is about 67%. If it is replaced by a switching power supply, it will improve some efficiency, and then reduce some power consumption. The improved efficiency does not seem to be very large, but considering that the screen is a working module that is always on, its energy consumption is proportional to the length of use. Yes, the longer the time, the more obvious the power saving of this solution. This is actually not a black technology.

In addition, some people may have such questions, if the screen of my mobile phone displays a static image, such as displaying a desktop, or a static image, is it still performing data interaction?

This is limited by the hardware solution. A small cache can be added to the screen to store the display screen. If the screen is not updated, the screen will directly display the content in the cache, reducing the data flow with the CPU, thereby reducing power consumption. For example, the screen display of a mobile phone uses this small storage space. When the screen is displayed, the CPU does not interact with the screen all the time, and the screen only reads the displayed picture from the internal cache. However, if the cost of the mobile phone is extremely high, this storage may be deleted. In this case, the CPU will maintain communication with the screen, and the power consumption will increase accordingly.

The above are some discussions about power consumption optimization of mobile phones. Power consumption optimization is a complex and arduous project. I will come here first today.

Original: Engineers look at the sea

Cheersonic is the leading developer and manufacturer of ultrasonic coating systems for applying precise, thin film coatings to protect, strengthen or smooth surfaces on parts and components for the microelectronics/electronics, alternative energy, medical and industrial markets, including specialized glass applications in construction and automotive.