The SMD touch switch is an inductive switch that allows the circuit to be turned on or off by manually pressing the button of the switch. Its main principle is to rely on the metal spring inside the switch to bounce and achieve the circuit on/off function. However, if the use of the touch switch is not handled properly, even some minor issues can affect the occurrence of the fault caused by the rear position. Below, I will mention to you the common fault symptoms of touch switches.

What are the common fault symptoms of patch touch switches

1. Due to the small volume components of the SMD touch switch, there are many shortcomings in the use of the switch. For example, do not frequently press the button switch. As the internal spring of the switch is subject to certain wear and fatigue every time it is touched, it can cause damage to the switch after a certain number of times.

2. When storing the SMD touch switch, in order to prevent discoloration of the terminal and oxidation of the internal spring of the switch, please do not use it in high temperature, high humidity environment or direct sunlight to prevent it from affecting the quality and performance of the switch.

3. In many cases, when the switch malfunctions, it is generally important not to disassemble it without authorization and handle it casually. For example, in cases where the switch response is not sensitive enough, operating and repairing without authorization is actually a very dangerous practice. On the one hand, there is no professional maintenance environment and technical understanding, but many high-end electronic products need to be operated in an environment that is insulated from dust, because dust can have a conductive effect. So much so that not only is there no problem with repairing the switch malfunction, but also the difficulty of increasing secondary maintenance caused by rearranging it.

4. Currently, most SMT touch switches experience an increase in resistance after undergoing furnace temperature and life tests. What is the general reason for this? In fact, the contact area between the switch's shrapnel and PIN pin is relatively small, which can cause the switch to not contact. Once the switch is not in contact, poor contact will occur when placed behind it. So in order to avoid affecting the effectiveness of the switch, it is important to pay attention to the resistance of the switch. The plating requirements for the spring and PIN pins are relatively high. If the plating is good, the resistance value will be low, and the wear life of the spring will be lower for the post installation.

Secondly, most personnel have reported that after welding the switch, there may be some buttons that cannot be pressed. In fact, this may cause some hidden dangers and faults during welding, which may have an impact. During the installation process of the switch, when the switch and PCB are tightly attached and the PIn pin is coated with solder paste, if the hole in the steel mesh is slightly larger, the solder paste will easily flow into the inside of the switch. Therefore, if there are foreign objects inside the switch, it is important to remember to handle them in a timely manner, otherwise the post position will definitely affect its travel, resulting in common situations where the switch cannot be pressed.

6. How to measure the quality of the patch touch switch? First, press the switches that need to be tested one by one with your hand, and there should be a clear feeling of being on or off. The sense of connection or disconnection is not obvious, or it cannot be pressed down at all, or it cannot bounce when pressed down. Check if the buttons on the switch are stuck or damaged. If there is indeed a problem with the switch, it should be replaced. The most handy tool for picking up and testing light touch switches is a multimeter. If it is a pointer (analog meter) using Ohmx1 gear, overlap the two probes (without distinguishing the positive and negative poles) on the two poles of the switch, press the switch, and the needle should swing with large spokes (not necessarily 0 ohms), indicating that the switch is functioning normally. If using a digital multimeter, use the 200 ohm gear as described above. When pressing the switch, the number on the display screen flashes. After pressing and holding, the number stabilizes and is generally less than ten or more ohms, indicating normal operation. The old touch switch used online may not display when measured at a 200 ohm gear, and requires a 2K or 20 or even 200K ohm gear to measure the resistance value. Most of these switches are no longer sensitive and should be replaced decisively. If there is no replaceable switch at the moment, 95% pure alcohol can be used in an emergency, dropped into the switch, and continuously pressed, which can generally be repaired.

Guangjiayuan Electronics has been focusing on the research and development and production of SMD touch switches for 12 years. While ensuring comparable product quality, it has a competitive advantage in price compared to its peers. We have now become a switch supplier for large enterprise groups such as Panasonic, Lenovo, Huawei, LG, and maintain good cooperative relationships. If you are interested in Guangjiayuan touch switch, you can come for consultation.