Create resistor divider topology with NTC thermistor as the top component of the voltage divider. The most common method of inrush current protection is by using an NTC Thermistor, so in this article, we will discuss more on NTC Thermistor and how to use one to prevent Inrush current in your designs. The resis-tance-versus-temperature response of a 10kΩ, NTC thermistor is shown in Figure 3. 3. NTC thermistors are used as ICLs (inrush current limiters) to protect circuits of electrical and electronic devices against inrush currents easily and effectively. Suppose you've been asked to design a linearized thermistor circuit, with a temperature range centered around +25 deg C. One technique is easy - place a resistor in parallel with the NTC thermistor. Widely used to control temperature in electronics devices such as alarms, thermometers, … This type of NTC Inrush Current Limiter circuit can be commonly found in power supply units like AC-DC Converters, or SMPS Circuits. The circuit usually relies on the NTC thermistor heating up due to the current passing through it. PARALLEL RESISTOR . Vref can be created using a DAC or voltage divider. The diagram below shows a microcontroller temperature protection circuit that employs a voltage-dividing circuit consisting of a combination of NTC thermistor and fixed resistors R S. When an overcurrent flows, the temperature of the NTC thermistor rises and its resistance decreases, thus suppressing the drive voltage of the microcontroller. The diagram below shows a microcontroller temperature protection circuit that employs a voltage-dividing circuit consisting of a combination of NTC thermistor and fixed resistors RS. 5. 4. R1 is chosen based on the temperature range and the NTC’s value. This condition implies that there is no self-heating of the thermistor as a conse-quence of current or voltage excitation. Applications based on current-time characteristic are: time delay, inrush current limiting, surge suppression and many more. These characteristics are related to the heat capacity and dissipation constant of the NTC thermistor used. If a voltage divider is used the equivalent resistance of the voltage divider will influence the gain of the circuit. thermistor, the resistance-versus-temperature circuits depend on the thermistor being operated in a “zero-power” condition. Monitoring NTC thermistor circuit with single-ended ADC Specifications Specification Calculated Simulated Temperature range 50ºC to 150ºC 50ºC to 150ºC ADC input range Within full scale range (< 3.3V) 785mV to 2.51V Design Notes 1. ( NTC = Negative Temperature Coefficient - the resistance decreases as temperature increases. ) voltage, switch the position of R1 and the NTC thermistor. NTC thermistor working in the cold-running circuit, the NTC resistance will be high when the environment is cold, the T1 transistor connected to the basin will not occur in the pot and T1 remains in t Using NTC Temperature Sensor With Arduino: A thermistor is a type of resistor whose resistance is dependent on temperature end have a electric resistance value for each absolute temperature. When an overcurrent flows, the temperature of the NTC thermistor rises and its resistance decreases, thus suppressing the drive voltage of the microcontroller. Advantages of NTC thermistors NTC thermistors are temperature-dependent resistors that employ special semiconductor ceramics with a negative temperature coefficient (NTC). 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