1, the role of the NTC line is to adjust the working state of the circuit by measuring the temperature change in the circuit to ensure the stability and safety of the circuit. The characteristic of NTC wire is that the resistance value decreases when the temperature increases, and the resistance value increases when the temperature decreases, so it can be used to measure the ambient temperature or monitor the temperature change in the circuit.
2, temperature control, ntc is a temperature control element, glued to the battery to detect the battery temperature.
3, NTC is also short for thermistor, and its series in AC circuit mainly plays a current insurance role. Parallel on AC sideThe circuit mainly plays the role of limiting the ultra-high voltage.
4, of course, ntc and gnd can not be short-circuited, unclear case it is recommended not to short-circuited at will, easy to light the line and component damage oh.
5, NTC50-9 meaning: resistance 50 ohms, diameter 9mm, CP lead, foot length 25mm. 2: Used to protect the charger, emergency can be removed. Function: at room temperature, the resistance is 50 ohms, which is relatively large, when starting, it plays a better current limiting role, after the power supply starts, the working current passes through the thermistor, making it heat up, and the thermistor resistance value decreases significantly (about 1Charging requires a charging line to charge ntc wireless charging , until now ntc wireless charging wireless charging, which shows that the development of science and technology continues to improve. The typical characteristic of thermistors is that they are sensitive to temperature and show different resistance values at different temperatures.
2, wireless charging thermistor has over current protection, over voltage protection, under voltage protection, temperature protection, short circuit protection, foreign body protection, overshoot protection, magnetic field protection and other functions. In particular, temperature protection is designed after heat is generated due to the magnetic fieldThere is temperature, when charging the magnetic field is constantly generated, the temperature will be higher and higher, so in the temperature protection installed NTC thermistor to monitor the protection of this wireless charging, it is to monitor the temperature around the coil.
3, buried in the charging circuit and the battery next to the temperature detection of the temperature NTC thermistor, and MCU together, you can track the instantaneous temperature change of wireless charging work.
What you want to ask is the resistance value of the Apple wireless charging moduleIs it a little? 100 ohms. According to the query cool rice network display. Apple wireless charging module can withstand 100 ohms of resistance ntc wireless charging , Apple wireless charging is Qi wireless charging standard, which is a wireless charging standard developed by WPC.
Wireless charging temperature measurement type NTC thermistor, the corresponding specification is MF52B, mainly used for power output (wireless charging socket).
Self-made wireless charging can not take the load reason ntc wireless charging : inside the chargerThe resistance is already high. There is a switching power supply inside the charger, and its oscillation circuit part has poor contact phenomenon, and it cannot be oscillated with a slight load. Measure whether the pin voltage to ground of the switching power supply stabilized oscillation thick mode chip is normal, and whether the components around the chip are normal. Check whether the switching transformer is normal, and whether the 24V rectifier filter circuit components are normal, and so on.
Magnetic fields and inductors are involved in the charging process. A pure resistance circuit refers to a circuit that contains only one resistor, while the circuit of a wireless charger contains an inductor coil, which is a necessary element to generate a magnetic field. Wireless by means of magnetic field inductionCharging, wireless charger is not a pure resistance circuit.
Open the shell of the wireless charging surface, inside is the wireless charging coil and thermistor, and there is a shielding cover on the circuit board above. Remove the wireless charging coil to expose the battery. The battery adopts Lishen 7V battery, 10Ah, 10000mAh capacity, the highest charging voltage 2V. There is a thermistor on the side of the battery to detect the battery temperature in real time. Remove the battery and circuit board from the mobile power supply housing.
A temperature detecting NTC thermistor ntc wireless charging is buried next to the charging circuit and battery, and the MCU works together to track the instantaneous temperature change of wireless charging.
Wireless fast charging is monitored by the IC to measure the voltage of the charging system, while the NTC (negative temperature coefficient thermistor) is responsible for detecting the internal temperature of the system, preventing the high temperature from causing excessive heat inside the wireless charger system to burn components and other safety problems, and can control the components to reduce the power in the case of high temperature, so as to reduce the temperatureDegree of effect.
As much as possible to improve ntc wireless charging your wireless charging conversion efficiency optimization control algorithm to enhance ntc wireless charging your heat dissipation effect plus heat sink or air cooling. The general wireless charging scheme will have a temperature control circuit and NTC thermistor, this function is mainly to prevent the heat generated by the circuit in the process of working is too high, burn components and so on.
The role of the thermistor is the function of overheating protection ntc wireless charging ; When the charging process overheats, there may be a potential risk of battery explosion or fire, with this protection, it will automatically cut off the charge to avoid danger.
There should be several places in the mobile phone to use the thermistor, the battery and the charger have, mainly to play the role of temperature compensation. Because the battery and charger will heat up in use, it will affect the size of the charging current, which is unfavorable to the battery, and after using a thermistor to compensate, the size of the charging current will not be affected by the temperature.
The magnetic charging phone case heats upThe reason is ntc wireless charging : the temperature control circuit is faulty. Wireless charging program will have a temperature control circuit and NTC thermistor, this function is mainly to prevent the circuit in the process of working to generate too much heat, burn components, etc., can also control the power components after generating too much heat, reduce the power, thereby reducing the temperature.