There are lot of temperature sensors both with analog & digital outputs. This project gives you an another temperature indicator which has been done with a digital sensor SMT160.
Although it is a digital sensor it does not gives out the temperature directly. The output is duty cycled modulated. The sensor can measure temperature from -45deg to +150deg.
The output duty cycle is D.C. = 0.320+0.00470 x t, here t is the temperature.
Therefore Temperature T = Dc / 0.0047
Read more: SMT160 based Temperature indicator