I’ve had good results with the DS1820 using a lookup table for C to F conversion. Checking results with a Thermo King dry well calibrator the DS1820 was on the on the money to the nearest full deg fahrenhite from 7*F to about 60*F, it was 1 deg high from about 60*F to about 80*F and on the money from about 80*F to 127*F. I checked two DS1820’s and both fail to function properly below 6*F. The lookup table was from 0*F to 127*F. If bit7 (.5C) is a one it forces a roundup to your higher Fahrenheit temp in your table read if you have two Fahrenheit degrees represented by the same Centigrade temperature. Both DS1820’s gave almost identical performance.