说明:
Portable electronics are growing rapidly, from mobile phones and MP3 players to PDAs, personal DVD players, and more traditional laptops, and people are revisiting many aspects of consumer and professional product design. This change is most evident in battery technology. Users want batteries to meet increasingly complex application needs, so they need more current and longer working hours. At the same time, the demand for small, lightweight products is also very strong, and the battery accounts for a considerable proportion of the volume and weight of any device. Therefore, manufacturers pay great attention to reducing their volume and weight. Another point is the requirement for fast charging, that is, reducing the time that the user waits for charging, and maximizing the advantage...
Release:
2018
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03
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27
Click:
55
说明:
Application principle and related circuit of PTC thermistor for overcurrent protectionproduct descriptionPTC thermistor for overcurrent protection is a kind of protection element for automatic protection and automatic recovery of abnormal temperature and abnormal current. It is commonly known as 'self-resetting fuse' and '10,000 times fuse'. It replaces the traditional fuse and can be widely used for overcurrent protection of motors, transformers, switching power supplies, electronic circuits, etc. PTC thermistors for overcurrent protection limit the residual current value by limiting the consumption in the entire line by sudden changes in resistance. . The traditional fuse cannot recover itself after the line is blown, and the PTC thermistor for overcurrent protection can ...
Release:
2018
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03
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27
Click:
365
说明:
Overcurrent protection circuit works When the circuit is in a normal state, the current through the overcurrent protection PTC thermistor is less than the rated current, and the overcurrent protection PTC thermistor is in a normal state, the resistance value is small, and does not affect the normal operation of the protected circuit. When the circuit fails and the current greatly exceeds the rated current, the PTC thermistor for overcurrent protection suddenly heats up and is in a high-impedance state, so that the circuit is in a relatively 'off' state, thereby protecting the circuit from damage. When the fault is removed, the PTC thermistor for overcurrent protection also automatically returns to the low resistance state, and the circuit resumes normal operation. ...
Release:
2018
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03
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27
Click:
73
说明:
Detailed description of the composition and principle of the switching power supply circuitFirs, the circuit composition of the switching power supplyThe main circuit of the switching power supply is composed of an input electromagnetic interference filter (EMI), a rectification and filtering circuit, a power conversion circuit, a PWM controller circuit, and an output rectification and filtering circuit. The auxiliary circuit has an input over-voltage protection circuit, an output over-voltage protection circuit, an output over-current protection circuit, and an output short-circuit protection circuit.The circuit block diagram of the switching power supply is as follows:Second, the principle of the input circuit and common circuits1, AC input rectification and filtering circuit principle:1...
Release:
2018
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03
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27
Click:
93