Temperature to Voltage Converter

This is a simple circuit which is used to Measure the Temperature by means of voltage levels.There are lot of temperature sensors in the market , this circuit is similar to that.



Conversion factor depends on the type of thermistor (NTC) resistance used. If you want to read the temperature directly on an universal measurement device then the value of R9 must be choosed, so that the desired sensitivity is achieved (R8 must be equal with R9).
The power supply voltage level is not critical; D1 zener voltage can be between 4.7 V and 8.2 V. The current consumption is about 12 mA.