National Instruments Module SCXI-1503 Instrukcja Użytkownika Pobierz pdf (Strona 41)

Chapter 4 Theory of Operation

Figure 4-4. Resistance-Temperature Curve for a 2,252 Ω Thermistor

The thermistor has been used primarily for high-resolution measurements

over limited temperature ranges. However, continuing improvements in

thermistor stability, accuracy, and interchangeability have prompted

increased use of thermistors in a variety of applications.

Thermistor Measurement Circuits

This section details information about thermistor measurement circuits.

The most common technique is to use a current-source, and measure the

voltage developed across the thermistor. Figure shows the measured

voltage V

equals R

× I

Figure 4-5. Thermistor Measurement with Constant Current Excitation

–

= I

x R

Thermisto

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National Instruments Module SCXI-1503 Instrukcja Użytkownika Strona 41