2pcs B value 3950 NTC thermistor temperature sensor 5K 10K 15K 20K 50K 100K 200K

NTC thermistor overview1. Definition of thermistorNTC is the abbreviation of Negative Temperature Coefficient in English. Its meaning is negative temperature coefficient.Its resistance value decreases with increasing temperature. Using this feature can be made into temperature measurement, temperature compensation and temperature control components, but also can be made into power-type components to suppress the surge current of the circuit. This is because the NTC thermistor has a rated zero-power resistance value. When it is connected in series in the power circuit, it can effectively suppress the startup surge current. And after the effect of suppressing the surge current is completed, the resistance value of the NTC thermistor is reduced to a very small extent by using the continuous action of the current).2. NTC thermistor parameter introduction【Nominal resistance】The nominal resistance value is the resistance value designed by the NTC thermistor, which is often marked on the surface of the thermistor. The nominal resistance value refers to the zero power resistance value when the reference temperature is 25°C, so it is also called the resistance value R25.【rated power】Rated power refers to the allowable power dissipation of the thermistor under long-term continuous load under atmospheric conditions with an ambient temperature of 25°C, a relative humidity of 45% to 80%, and an atmospheric pressure of 0.87 to 1.07Pa.【B value range】The B value range (K) is the thermal sensitivity index of the negative temperature coefficient thermistor, which reflects the resistance change between two temperatures. It is defined as the ratio of the difference between the natural logarithm of the zero-power resistance value at two temperatures and the reciprocal difference of this temperature.【Zero power resistance value】Measure the resistance value of the thermistor at the specified temperature. When the resistance value change caused by the internal heating of the resistor is relative to the total measurement error, the measured resistance value can be ignored.【Dissipation coefficient δ(mW/℃)】The dissipation factor refers to the ratio of the power consumed by the thermistor to the change in ambient temperature.【Time constant τ(s)】The time constant τ(s) refers to the time required for the thermistor resistance to change 63.2% when the ambient temperature changes from a specific temperature to another specific temperature under the zero power state.【Temperature Coefficient of Resistance】The temperature coefficient of resistance refers to the relative change in the resistance value of the thermistor when the ambient temperature changes by 1°C. After knowing the resistance temperature coefficient of a certain model of thermistor, the actual resistance value of the thermistor at the corresponding temperature can be estimated.3. Identification and detectionNTC thermistor is cheap, widely used in electronic products, and has a variety of packaging forms, which can be easily applied to various circuitsNTC thermistors have different resistance and temperature characteristics according to different materials and processes.There are many models and specifications of NTC hot wire resistors. Well-known foreign manufacturers include Japan's Mitsubishi, Japan's TDK, Japan's Tateyama, South Korea's EXPAND, etc., and there are also many domestic brands with very good quality.There are many types of NTC hot wire resistors with different shapes. The naming standard of negative temperature coefficient thermistor consists of four parts. Among them, M stands for sensitive components and F stands for negative temperature coefficient thermistor.Some thermistor models produced in China usually also include the thermistor's resistance value, error and other information. The following is the identification of NTC thermistor:①CWF ②□ — ③103 ④J ⑤3380 includes the following information.①NTC temperature sensor;②The package form and size of the sensor head;a. On behalf of epoxy resin packaging;b. Represents packages such as aluminum shell, copper shell, stainless steel, etc.c. Represents plastic case package;d. On behalf of adding a fixed metal sheet;e. Represents a special form of closure.③Nominal resistance value R25, such as 103=10×10 =10000Ω=10kΩ.④Nominal resistance value accuracy code:F represents ±1%, G represents ±2%, H represents ±3%, and J represents ±5%.⑤B value (25℃/50℃, 3380 means B value is 3380K).