kukulo:
I implemented project 03 (love-o-meter) but the value measured by the sensor varies between 144 and 146, that means 0 volts and a temperature of -50.00 degrees.
The formula for the voltage should be;
Voltage = (sensor / 1024) X 5.0
So if you had a sensor value of 145 then it should be (145/1024) X 5 = 0.71 volts, not 0 volts.
Temperature = (voltage - 0.5) X 100
So if you had a sensor value of 145 and 0.71 volts, then temperature will calculate to (0.71 - 0.5) X 100 = 21 degrees C.
Looks like your TMP 36 is working correctly.