Wireless charging is no stranger to everyone. Especially with the entry of leading mobile phone brands such as Apple, Samsung, Xiaomi, Huawei, OPPO, vivo into the wireless market, many new mobile phones have included the wireless charging function. However, in addition to the consumer power supply field, wireless charging power also has great development potential in other areas: medical health, household appliances, robots, AVG, drones, electric vehicles, etc., for instance.
SPONSORED | Choosing The Right DC-DC Converter For Your Critical Medical Application
Unlike the consumer power market, these emerging markets tend to attach great importance to the stability and safety of high‑watt wireless charging technology. Along with the advance of artificial intelligence of robots, AVGs, etc., the wireless charging function has gradually gained market recognition because of its advantages of non-exposed electrodes; contactless, unnecessary precise alignment; safe and leak-free charging; and the saving of labor costs for maintenance and repair. The development prospect of wireless charging is just promising.
MICROCHIP launches a 300W wireless charging module
Chongdiantou, one of the most influential charging technology media in China, has recently learned that MICROCHIP has launched on its official website a 300W medium-power wireless charging solution. As the world’s leading supplier of single-chip microcomputers and analog semiconductors, the launch of this solution signifies the fact that MICROCHIP has already begun deploying industrial-grade wireless charging technology.
Chongdiantou’s editorial team have also purchased a set of 300W wireless charging solution from the official website of MICROCHIP via online order placement. Today, we are going to share with you the hands-on experience and simple evaluation of performance of this 300W high-power wireless charging solution. The set of this MICROCHIP 300W wireless charging module is divided into two parts: the transmitter and the receiver, both of which are designed with green PCB boards.
Firstly, let us briefly introduce the transmitter. This module consists of three PCB boards: the left side of the main PCB board on the front is equipped with a wireless charging transmitter control circuit, and the right side is the transmitter coil. The NFC detection coil around the wireless charging transmitter coil is printed on the PCB board; there is an OLED display screen installed on the PCB board connected by the pin headers below, together with its operational keys.
Materials of MICROCHIP 300W wireless charging module
Following is the detailed introduction to the structure and materials of the MICROCHIP 300W wireless charging module. Let us start with the wireless charging transmitter module.
The wireless charging transmitter model is EVB-WP300, which has passed the FCC certification. In the lower left corner is the master control chip of wireless charging transmitter of MICROCHIP, accompanied by a driver chip in the middle, two coil-driven metal oxide semiconductor field effect transistors of the same type on the right, and six NPO resonant capacitors.
Next, let us take a look at the wireless charging receiving module:
MICROCHIP 300W wireless charging module power-on test
After introducing the appearance and basic materials of the MICROCHIP 300W wireless charging module, let us power it on to do some simple tests. Since the existing DC power supply and load in the laboratory can only support up to the maximum power of 150W, the efficiency test for this module is limited to within 150W. Furthermore, the test data may vary due to different test environments, and the results are for reference only.
1. FOD foreign body detection and NFC detection
After connecting the Tx sending end of the wireless charging module to the 24V power supply, we can see that the display screen has been successfully lit and the entire transmitter has entered the normal standby state. From the content displayed on the screen, we can tell that the frequency of the transmitter is 85.8KHz, the input voltage is 23.99V, and it is currently in the standby state, with the current of 0.02A and the standby power consumption about 0.4W.
Firstly, for the FOD foreign object detection, a coil is put directly on the wireless charging coil to trigger the function of foreign object detection. “Metal-FOD” will be displayed on the screen, and the system will issue a warning sound; the power is still maintained at 0.4W, which indicates that there is no output.
In addition to detecting larger metal pieces such as coins, this system can also detect the presence of tiny foreign metal objects, like a paper clip, very sensitively by triggering the foreign object detection function.
Subsequently, we replace the metal piece with a bank card; this system can still detect the NFC. It is very sensitive.
After testing the FOD foreign object detection and NFC detection functions, let us test the efficiency of the entire wireless charging system. At the power supply side, we use two DC power supplies in parallel to provide 24V10A output capacity, and at the load side, we use ITECH IT8511A, with a maximum load power of 150W. By adjusting the current of the electronic load, we obtain efficiency data at different power levels.
In no-load mode, it can be seen through the Tx transmitter display that the input voltage is 23.96V; the current is 0.23A, and the power is about 5.5W.
Then the current of the electronic load is adjusted to 1A. At this time, the voltage of the load terminal is 23.95V (let us ignore the voltage drop), the load power is 23.94W, and the voltage of the Tx transmitter terminal is 23.94V, the current is 1.34A, and the power is about 32W. It can be told that the efficiency is about 74.81%.
Then we proceed to adjust the current of the electronic load to 2A. At this time, the voltage of the load terminal is 23.94V (let us ignore the voltage drop), the voltage of the Tx transmitter terminal is 23.92V, the current is 2.37A, the emissive power is 56.6W, and the overall efficiency is about 84.55%.
When the load current is adjusted to 3A, the voltage at the load end is 23.933V (the voltage drop is negligible), the Tx transmitter voltage is 23.9V, the current is 3.42A, the emissive power is 81.7W, and the overall efficiency is about 87.87%.
When the load current is 4A, the voltage at the load end is 23.923V (the voltage drop is negligible), the Tx transmitter voltage is 23.88V, the current is 4.49A, the emissive power is 107.2W, and the overall efficiency is about 89.26%.
When the load current is adjusted to 5A, the voltage at the load end is 23.913V (the voltage drop is negligible), the Tx transmitter voltage is 23.86V, the current is 5.59A, the emissive power is 133.3W, and the overall efficiency is about 89.67%.
When the load current is adjusted to 6A, the voltage at the load end is 23.902V (the voltage drop is negligible), the Tx transmitter voltage is 23.86V, the current is 6.66A, the emissive power is 158.9W, and the overall efficiency is about 90.25%.
We proceed to adjust the load current to 6.274A. At this time, the load terminal is running at a maximum power of 150W, the voltage is 23.9V (the voltage drop is negligible), the Tx transmitter voltage is 23.84V, the current is 6.99A, the emissive power is 166.6W, and the overall efficiency is about is 90.00%.
Finally, the test data of the wireless charging solution are organized into a curve diagram. It can be seen that the efficiency of the solution is relatively low in low-power current mode, and the efficiency is about 74.8% when 1A current is loaded; as the load current increases, the efficiency of the entire wireless charging system also increases, with the highest efficiency even exceeding 90%. This is higher than that of many traditional power adapters and is very rare for wireless charging systems.
For the heavy-duty wireless charging system, temperature rise is another important parameter for measuring the performance of the solution. Based on the existing test equipment, Chongdiantou.com conducts a 150W load and aging test for the wireless charging solution at a room temperature of about 25°C, together with a FLIR E4 infrared thermograph used to check temperature at half-hourly intervals.
As mentioned at the beginning of this article, there are many application scenarios for heavy-duty wireless charging technology, and blue ocean strategy can certainly be applied to the market. Meanwhile, compared to consumer-grade wireless charging, the technical difficulty of high-power wireless charging solutions is also greater with higher threshold. The set of 300W wireless charging module that Chongdiantou.com has got this time is based on the development of a full set of MICROCHIP master control chip, and the whole set of the module is ingeniously designed and exquisite in workmanship. The transmitter has its own display screen, which is convenient for users to debug.
The specifications of this wireless charging module adopt 24V DC input/24V DC output. To our understanding, this wireless charging module can also be set to 12V DC input/12V DC output and 36V DC input/36V DC output according to the actual application needs of users for meeting the demands for different product applications.
In terms of its performance, apart from the highlight of 300W heavy power, this wireless charging module also has sensitive FOD foreign object detection and NFC functions, which can ensure the safety of the solution in mass production. According to the result of our simple test, since the no-load power consumption of the wireless charging module is about 5-6W, the efficiency becomes slightly lower when the load current is relatively small; the larger the load current is, the higher the efficiency becomes, and the measured 150W load efficiency can reach up to about 90%.
At the same time, the wireless charging module is able to run smoothly under 150W load power. Without active heat dissipation, the highest temperature in half an hour is about 87°C, and the highest temperature at the receiving end is about 90°C in 1 hour. It is undoubtedly a very good performance.
This complete set of solution launched by MICROCHIP for the high-power wireless charging market is expected to enable products including robots, AVGs, drones, and electric vehicles to enter the wireless charging era ahead of schedule in the coming future.
Visit to the version of original article: https://www.chongdiantou.com/archives/107978.html
You must Register or Login to post a comment.
This site uses Akismet to reduce spam. Learn how your comment data is processed.