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**One**

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**PTC thermistor resistance-temperature characteristics:**

Refers to the specified voltage, zero power resistance of the PTC thermistor value relationship between body temperature and resistance.

**Rated zero-power resistance value (R25/Rn)**：Referring to the zero power resistor at 25 ℃, unless the customer specifically another temperature.

**Minimum resistance (Rmin)**：Refers to the starting from room temperature 25 degrees, series of temperature curve corresponds to the minimum resistance value, Rmin corresponding to the temperature is Tmin.

**Switching temperature (Tc)**：When the resistance begins rendering step increases the temperature to switch the temperature, that is when the resistance rises to twice the minimum resistance value (Rmin) during which temperature, also known as the Curie temperature.

**The maximum working voltage (Vmax)**：In the maximum allowable ambient temperature, PTC thermistor can continue to bear the maximum voltage.

**Maximum current (Imax)**

**：**Means the maximum working voltage, the maximum current allowed through PTC Thermistors.

**Not current (Int)**

**：**No current rated current or current, means under specified conditions of time and temperature, without PTC thermal resistor with high resistance state maximum current.

**Operating current (It)**

**：**Under specified conditions of time and temperature, the PTC thermistor resistance is step-increases the minimum current.

**Maximum voltage temperature range**

**：**PTC thermistor can still work at maximum voltage ambient temperature range.

**Dissipation factor (δ)**

**：**Power dissipation in the PTC thermistor changes and component ratio of the corresponding amount of temperature change, known as the dissipation factor (MW/degrees: δ-=P/(T-Tr)

**Withstand voltage**

**：**Refers to time and temperature conditions, the PTC thermistor can withstand the maximum voltage exceeding this voltage, PTC thermistor will penetrate.

**Thermal time constant (τ)**

**：**In the still air, PTC thermistor temperature changes with ambient temperature 63.2% of the difference of the time required.

**Residual current (Ir)**

**：**Means the maximum working voltage, PTC thermistor resistance after the jump, the current state of thermal equilibrium.

Temperature coefficient (α-t)：Can be expressed as：

αT=（1/R

_{T}）×（dR_{T}/dT）So αT=（LnR

_{2}- LnR_{1}）/（T_{2}- T_{1}）×100%/℃Generally refers to R

_{1}=R_{Tc+10}_{℃} R

_{2}=R_{Tc+25}_{℃} R1, R2, the temperature is T1, T2, and Curie temperature of 10 degrees Celsius and 25 degrees centigrade higher, respectively.

Minimum value of temperature (TRmin): minimum resistance Rmin appears corresponding to the temperature.

**The upper limit temperature (UCT)**

**：**The maximum ambient temperature of the thermistor can continue to work.

The lower limit temperature (LCT)：The minimum ambient temperature thermistor can continue to work.