Temperature versus ADC value

The example temperature table below shows temperature versus thermistor ADC value (hex and dec) with gain=1, and ADC mv for a sample thermistor. For full thermistor characteristics of the sample device search for Murata part NCP18XH103J03RB. The table assumes the nominal Vref of 3300mV.

The conversion to mV uses the formula

adc_mV = (Vref * adc_value)/adc_max_value

This table is accurate within a few degrees celsius.

Note: Adjust as necessary if Vref is not equal to 3300mV. Different thermistors may have a different correspondence between voltage and temperature. To create an accurate table for your particular thermistor you can calibrate with an accurate thermometer.

ADC value
hex
ADC value
dec
ADC mvTemp (deg. C)Temp (deg. F)
0xBB229942413032.0
0xB8F29602385133.8
0xB6C29252357235.6
0xB4828892328337.4
0xB2428532299439.2
0xAFF28162269541.0
0xADB27802240642.8
0xAB627422210744.6
0xA8F27042179846.4
0xA6A26672149948.2
0xA44262821181050.0
0xA1D259020871151.8
0x9F7255120561253.6
0x9D0251320251355.4
0x9AA247419941457.2
0x983243619631559.0
0x95C239619311660.8
0x935235819001762.6
0x90E231818681864.4
0x8E7228018371966.2
0x8BF224018052068.0
0x899220117742169.8
0x872216317432271.6
0x84C212417122373.4
0x825208616812475.2
0x7FF204816502577.0
0x7D9200916192678.8
0x7B3197215892780.6
0x78D193315582882.4
0x768189615282984.2
0x742185914983086.0
0x71E182314693187.8
0x6F9178614393289.6
0x6D5175014103391.4
0x6B1171413813493.2
0x68E167913533595.0
0x66C164413253696.8
0x649160912973798.6
0x6271576127038100.4
0x6061542124339102.2
0x5E41509121640104.0
0x5C31475118941105.8
0x5A31443116342107.6
0x5841412113843109.4
0x5651381111344111.2
0x5461350108845113.0

A LUT file is a CSV file with the following format:

<Raw ADC Value (0-4095)>,<Floating point number>\r\n

Values are in decimal format.

A LUT file corresponding to the above table of characteristics has the following content:

0,125
1350,45
1381,44
1412,43
1443,42
1475,41
1509,40
1542,39
1576,38
1609,37
1644,36
1679,35
1714,34
1750,33
1786,32
1823,31
1859,30
1896,29
1933,28
1972,27
2009,26
2048,25
2086,24
2124,23
2163,22
2201,21
2240,20
2280,19
2318,18
2358,17
2396,16
2436,15
2474,14
2513,13
2551,12
2590,11
2628,10
2667,9
2704,8
2742,7
2780,6
2816,5
2853,4
2889,3
2925,2
2960,1
2994,0
4095,-125