DS18B20

It is a very good choice to measure temperature due to its ease of use and accuracy ( 9-12 bit)

The DS18B20 has also an alarm function where you can program upper and lower values

• Input Voltage : 3-5v
• Accuracy : ±0.5°C
• Temperatures Measurement Range :–55°C ~ +125°C
• Power Supply Current : 1mA/3-5.5V
• Resolution : 12 bits
• Encapsulated Type : TO-92
• Pins: 3 (1 digital, GND, Vcc)
• Output Current : 4mA
• Surface Mounting Type : Through-hole