With the continuous development of the domestic economy and the rapid rise of the domestic electronics industry, the demand for PTC chip fuse products has increased from small to large, which has greatly promoted the development of PTC chip fuses. What are the trends in the development of PTC chip fuses in terms of quality, environment, labor costs, industry, etc? For the application of PTC patch fuse protection in circuits, using PTC has taken the lead and is in line with the trend. The statement that it will develop and grow is currently correct. In order to adapt to modern automatic production, the demand for SMD devices is increasing, and plug-in PTCs will be limited to the application of high voltage and high current products, so SMD devices are the development trend. The current specifications are developing towards both ends of the size range and towards smaller sizes. Continuously innovate by improving voltage levels. Without PTC, it violates the trend and will decline. D
PTC self recovery patch fuse is used for overcurrent protection between motherboard power supplies and backend equipment overcurrent protection. Regarding the issue of PTC self recovery patch fuse for short circuit and overcurrent protection outside the microcontroller. The output port of the microcontroller has direct external wiring. If there is a wiring error, it is easy to burn out the IC. In addition, if there is a load overload, it can also burn out the IC. Therefore, the output port of the I/O port is usually connected in series with a self recovery patch fuse for overcurrent protection. In microcontroller circuit protection, disposable fuses or fuse resistors are also used for protection. Glass tube fuses and fuse resistors are traditional protection applications, with the advantage of low cost. However, this application has gradually been phased out, and PTC self recovery patch fuses have been used instead. Due to the fact that disposable fuses only fuse for overcurrent
How does PTC self recovery fuse achieve protection function? The actual process of PTC overcurrent circuit protection is not yet clear, and its superiority needs further exploration. So far, it is believed that PTC is a polymer based self recovery fuse that can limit current. The principle of PTC self recovery fuse is to limit potentially harmful overload currents within a safe range. Specifically, excessive current flowing through the device can lead to an increase in internal heat (I2R), resulting in a temperature rise in PTC and an increase in its resistance. Before overheating occurs, PTC resistance usually only accounts for a small portion of the total impedance of the circuit. The increase in resistance of polymer PTC self-healing fuses has a non-linear characteristic, and such relatively large resistance will reduce or limit the current in the circuit to a safe range. The transition point from low resistance to high resistance is called the "jump point". The heat generated
Usually, the occurrence of circuit board fire accidents is related to the failure of the varistor to disconnect from the circuit in a timely manner, resulting in varying degrees of short circuits in the system power supply. Below, I will share with you the drawbacks of using a single patch fuse current protection method to deal with the failure of the varistor, and propose that the best protection method for the failure of the varistor is over temperature protection. Zinc oxide varistor MOV is a polycrystalline semiconductor ceramic component made by a typical electronic ceramic process with zinc oxide as the main body and various metal oxides added. MOVs have a unique grain boundary structure. Under a certain electric field, the conduction of grain boundaries changes from hot electron emission conduction to electron tunneling conduction, and their resistance value sharply decreases with the increase of voltage. They have excellent nonlinear volt-ampere characteristics. Therefore,
Patch fuses can be divided into disposable patch fuses and patch self recovery fuses. After being protected by a disposable fuse, it needs to be replaced. After being protected by a self recovery fuse, it can be restored and reused after power failure. But what should we pay attention to when choosing patch fuses? The editor suggests selecting fuses based on the following aspects: normal current, fusing current, open circuit voltage, short circuit current, impulse current, and ambient temperature. Short circuit current: We refer to the maximum current that flows when a circuit is short circuited as the short circuit current. For various fuses, the rated breaking capacity is specified, and we must be careful not to exceed the rated breaking capacity when selecting fuses. If a fuse with a small breaking capacity is selected, it may cause the fuse to rupture or cause a fire. Impulse current: Observe the waveform of the impulse current (pulse current waveform) and calculate its ener
(1) With the demand for the development of electronic products, the functionality (integration) of ICs is also becoming stronger, and their "value" is naturally becoming more noble, so it is necessary to strengthen protection. (2) In order to reduce power consumption, reduce heat generation, and extend service life, the working voltage of semiconductor components and ICs is getting lower and lower. According to SIA (American Semiconductor Industry Association) statistics, the current working voltage is around 1.5V, and it will drop to below 1.2V by 2004. Therefore, its ability to withstand overcurrent/overvoltage needs to adapt to new protection requirements. (3) There are more and more mobile electronic products, such as handheld devices, PDAs, laptops, camcorders, digital cameras, jukeboxes, etc. These electronic products require battery components as power sources, and protective components must be equipped in both battery components and battery chargers. (4) In modern luxury