Let's Control It

Hi, newbie here!
I want to use max6675 to make a resistance furnace temperature detection system.
Do I still need to use the ds18b20 sensor?
So...
In which link should I use if I need it
This is the datasheet (https://www.utmel.com/components/max667 ... son?id=555）I reference when I use max6675.
Did anyone use max6675?
Asking some good idea.
Thanks in advance!

It actually depends on the temperatures you are expecting to measure. The DS18b20 sensor has a hard limit of +125 degrees centigrade, and I would be surprised if the temperature in a furnace doesn't exceed that. It can be used to measuring the external temperature of the furnace, but even there I'm not sure I would use it for.

The max6675 IC is expecting a thermocouple to be connected for doing the actual measurement, so that has to be added as well. Just using that chip is not going the give any usable result
The advantage of a thermocouple is that is usually can handle much higher temperatures.