That is to say, when charging wirelessly, the induced current can directly pass through the front display screen, and there is no need to reverse the phone on the back. Apple's new unlimited charging method will undoubtedly bring a new storm to the future of wireless charging.
And wireless charging itself is a storm.
The development of science and technology makes us farther and farther away from "bondage". For all kinds of electronic products, wired charger is the most important accessory, but the crazy winding of charging cable makes us feel that we have lost our freedom in the convenient era.
In this case, wireless charging came into being.
Now, when we charge the portable equipment, the common method is to use the charger to supply power through the power cord. Wireless charging technology does not need to use connectors, metal contacts and other media, but only needs to be placed on the charging base to charge. Wireless charging does not need a conventional charger and power cord, which can improve the waterproof and reliability of the equipment, and there is no bad connector. At the same time, the wireless charging equipment has standard specifications, and one power supply equipment can be used for various terminals.
From the technical classification, wireless charging can be divided into three categories: electromagnetic induction wireless charging, electromagnetic resonance wireless charging and radio frequency (RF) wireless charging.
At present, the popular wireless charging is electromagnetic induction charging, which is basically adopted by most mobile phones and headphones supporting wireless charging in the market. The principle of electromagnetic induction charging is not complicated: the current passes through the coil, and the coil generates a magnetic field, and the magnetic field generates induced electromotive force on the nearby coil to generate current. The charging conversion rate of this charging method is usually above 70%, and the cost is low, so it is popularized quickly. However, when charging, both the charger and the charged device must have coils, and the coils of both must be aligned to work normally under touch.
In order to solve the above problems, electromagnetic vibration wireless charging technology appeared. Its principle is that the transmitter and receiver meet at the same * * * vibration frequency and transmit power through the * * * vibration effect. Like electromagnetic induction charging, it can be charged without aligning the position of the coil, and it can be charged in a wider range (about 10cm), but its disadvantage is that the charging efficiency is low, and the farther the distance, the greater the transmission power and the greater the loss.
In fact, the above two wireless charging technologies are not really "wireless" in nature, and the equipment needs to keep a certain distance from the charging base to realize power transmission.
In order to realize real wireless charging, wireless radio frequency technology came into being. This new long-distance charging technology radiates radio waves through the antenna of the transmitter, and the receiving device receives the energy carried by the radio waves to complete "long-distance charging". This charging method covers a much wider range than the first two technologies.
At present, the electromagnetic induction technology used in wireless charging of mobile phones is limited, but it is widely used by manufacturers because of its low technical difficulty and low cost. However, due to some obvious limitations of this technology, wireless charging of mobile phones is not particularly popular, and wired charging still occupies the vast majority of charging methods.
There are many short boards for electromagnetic induction wireless charging: the coils need to be aligned when charging, the charging distance is required to be close, and the number of rechargeable devices is small. These three shortcomings limit the development of electromagnetic induction wireless charging.
Regarding the alignment of the charging coil, the experiment shows that if the device has no magnetic attraction, it is impossible to automatically align the charged wireless charger with the mobile phone. Even if the mobile phone and wireless charger are carefully aligned with the coil position, wireless charging consumes 39% more power than wired charging in the process of electric-magnetic-magnetic-electric conversion. Because this part of the electric energy is not actually charged into the battery of the mobile phone, it is equivalent to being simply wasted.
When the truly mature and low-cost electromagnetic vibration and radio frequency wireless charger appear, wireless charging can really realize the convenience that everyone imagines is much higher than plug-in charging. Perhaps in the field of consumer electronics, wireless charging technology will directly transition from the existing electromagnetic induction wireless charging to air charging. From limited wireless to true wireless.
In order to solve the problems of energy loss and slow speed that may exist in wireless charging, the power of wireless charging also increases. From the initial 5W to the later 30W, 202 1 year, many chip and terminal manufacturers have introduced 40W and 50W wireless charging products.
Wireless charging solution is mainly composed of receiving end and transmitting end. The transmitting end is connected with the power supply and is responsible for sending electric energy, and the wireless transmitting coil is responsible for sending the energy out; The receiving end is generally installed on electronic products and is responsible for receiving electric energy. Generally speaking, in the wireless charging solution, the chip and system integration design at the receiving end is more profitable and the technical barrier is relatively high.
Renesas latest 60W wireless charging and receiving chip
20211/in October, Renesas Electronics launched the world's first wireless power receiver P94 18 with 60W power, which can create faster wireless charging for smart phones, portable computers and notebook devices. P94 18 wireless power receiver adopts Renesas's unique WattShare technology, which can provide up to 60W power in a single chip with high integration. It belongs to a single-chip wireless power receiver/transmitter IC, which can be configured to send or receive AC power signals through magnetic induction.
50W Wireless Charging Solution
ST is also an important player in the field of wireless charging. In June 2020165438+1October, ST launched the latest generation of Qi wireless super fast charging chip STWLC88. The output power of the new product is as high as 50W, which can meet the needs of consumers to quickly supply power to personal electronic products such as mobile phones, tablets and notebook computers without plugging in, and it is comparable to wired charging in terms of safety and charging speed. In the application of mobile phone wireless charging, the charging speed of the new generation 50W wireless charging IC is twice that of the previous generation.
Volta semiconductor high-power wireless charging chip
In fact, in terms of high-power wireless charging, domestic chip manufacturers are also making efforts. In the field of wireless charging chips, Vodafone Semiconductor has introduced receiver chips NU 16 19(40W) and Nu19A (50W), as well as NU 15 13(45W) and Nu.
The wireless charging receiver scheme of Xiaomi 1 1 uses the chip NU 16 19.
202 1, 1 1 year1October, Vodafone Semiconductor launched its third-generation wireless charging SOC chip NU 1708, which is a fully integrated emission chip supporting 5~30W wireless charging, combining the traditional first-generation and second-generation MCU chips and the full-bridge power supply.
Nanxin Semiconductor introduced high-power TRX bidirectional wireless charging chip.
Nanxin Semiconductor also continues to increase its R&D investment in wireless charging transmitters and receivers. In 20021and 10, Nanxin introduced two heavy products: the third-generation transmitter 15W SOC chip SC9608 and the first high-power 50W RX receiver chip SC962 1.
With its high integration, TX SOC chip SC9608 has been sought after by many customers and has been put into trial production in many customers. The launch of RX SOC chip SC962 1 also marks that the wireless charging layout of Nanxin has been further broadened, and it has officially entered the mobile phone market from the transmitter accessories market, providing mobile phone manufacturers with more competitive product choices.
The infinity of application scenarios has led to the penetration of wireless charging into the automotive field, and the vehicle-mounted wireless charging has also broken ground. In-vehicle wireless charging also gets rid of the bondage of charging cable, which improves convenience and driving safety. At present, many domestic and foreign manufacturers have introduced wireless charging solutions for automotive applications.
NXP Vehicle Wireless Charging Chip
NXP's vehicle-mounted multi-device wireless charging scheme provides three main control chips, namely MWCT 22c3a/MWCT 20c3a/MWCT 2013A, which are the second generation wireless charging and transmitting chips of NXP. Compared with the previous generation chips, they mainly optimize the peripheral circuit and conduction loss of the chip, support two isolated channels, and only need one chip to charge two wireless receiving devices on a terminal, which not only reduces the BOM cost, but also reduces the cost.
Intelligent control chip of Vda semiconductor vehicle instrument transmitter
202165438+February, two intelligent full-bridge chips NU80 15Q and NU8040Q of Vodafone Semiconductor used for wireless charging and transmitting passed the vehicle code certification. Both chips are intelligent control chips of wireless charging transmitter, and full-bridge MOS transistors and drivers are integrated in the chips. Among them, NU80 15Q supports the highest wireless charging output of 15W and the power supply voltage range of 4V-21V.. NU8040Q supports 40W wireless charging output, 4V-2 1V power supply voltage range and -40 to 105 ambient temperature range.
Yichong Semiconductor provides solutions for the fast charging technology jointly launched by BYD and Huawei.
In the automotive field, Easy Charge Semiconductor also provides a complete set of solutions for the 50W super wireless fast charging technology jointly launched by BYD and Huawei. In 20 12, Yichong Semiconductor developed the world's first wireless charging scheme for vehicles, which was successfully mass-produced on four Toyota models and has been continuously shipped to this day. The 50W wireless charging vehicle-mounted front-end solution launched this time is a car logo chip CPSQ8 100 based on the experience of the first generation of products and the mass production and shipment of more than 10 million IC's. CPSQ8 100 is specially designed for wireless charging system, which integrates all low-power parts, including wireless charging protocol, MOS driving circuit, Q value detection and demodulation circuit.
The storm in the era of wireless charging struck early, and chip manufacturers at home and abroad also actively laid out the layout, saw the wireless and infinite development trend of wireless charging, and resolutely walked on their own road. I believe that in this storm, they can also draw a blueprint for the era of wireless charging.