The last board was not designed very well in terms of touch buttons. During the last test, I felt very confused and had no idea what to do. This time, I saw that the capacitive touch buttons on the board were improved and spring-leaded touch buttons were used, so I applied for a test evaluation. After getting the board, I compared it with the last board. There were many improvements and the routines were also easy to use. On the last board, K3 and K4 were self-capacitive touch buttons, and K1 and K2 were mutual-capacitive touch buttons. I studied it for a long time last time but didn't understand it, so I gave up.
On this board, K1, K2, K3, and K4 are all self-capacitive touch buttons, and the commonly used spring-lead method is used. The advantage is that the spring elasticity is used in the product to make the metal sheet close to the touch panel.
First, test the capacitive touch buttons through the official routines. Use the official routine to build the project, compile, burn, and reset. The response of the capacitive touch button can be seen through the debugging serial port. The result shows that the touch button action is correctly recognized, which is very sensitive and fast. Since there is a touch button with spring lead-out, it is natural to test the adaptability to touch panels of different materials. Paper business cards, PVC boards, and thin glass were tested respectively, and it was found that K1 and K2 recognized well, and K3 and K4 were also normal when the thickness was relatively thin, but when it was slightly thicker, K4 would be worse, and K3 would be worse. Analyzing the reasons, I think it is caused by the different touch button routing. Since the evaluation board has to lead all pins to JP2 and is compatible with 3 types of packaged MCUs at the same time, and I didn’t pay much attention to the wiring, the leads corresponding to the K3 and K4 touch buttons were first led to the socket, and then to the MCU, and the routing was slightly tortuous. I guess this may be the reason why the K3 and K4 touch buttons are not as good as the K1 and K2 touch buttons for the slightly thicker touch panel. If there is a PCB diagram, it will be clearer to light up the relevant lines for comparison.
Suggested improvements (or attention in your application) 1. The touch button routing is not reused with other pins, but directly connected to the MCU pins. 2. It is recommended that Qinheng gather people to write some application guides for its own MCU to facilitate users to better use Qinheng's MCU. If you want to learn from a role model, it is recommended to look at the manual of MICROCHIP (excluding ATMEL, which was acquired some time ago). In addition, TI's is also good. Here is a link to TI's touch button design guide [url=http://software-dl.ti.com/msp430/msp430_public_sw/mcu/msp430/CapTIvate_Design_Center/latest/exports/docs/users_guide/html/CapTIvate_Technology_Guide_html/markdown/ch_basics.html], you can also learn from it. Domestic products should be self-reliant. Everyone (merchants and developers) should work together and do their part to make our products better.
This content was originally created by EEWORLD forum user yang_alex. If you need to reprint or use it for commercial purposes, you must obtain the author's consent and indicate the source
提升卡
变色卡
千斤顶
京公网安备 11010802033920号
