if you want to speed up code try to remove float divisions too
Vout = (Vin/1024)*(value ); ==> Vout = value * Vin * 0.0009765625; // == 1/1024
TempK = Beta/(log(Rntc/R25)+(Beta/T0)); ==> Beta/( log (Rntc * C1) + C2); // C1 = 1/R25; Beta /T0 is probably const