DS18B20 Sensor with external power input

Hello,
I am making some tests with DS18B20 sensor. I am using 4,7kOhm resistor between the 5V and the output from the sensor, the 5V are connected directly to the Arduino 5V Power and everything seems to be working as expected.

The issue I am having is that I want to use external power for the seonsors, I connected 12V power adapter to LM340LAZ-5.0 Voltage Regulator, and the output from the voltage regulator to the DS18B20. Before connecting the seonsor i tested the line with multimeter and the voltage is exactly 5V. The problem is that i do not get any data back on the Arduino this way. Am I missing something?

Apparently I had to connect the ground from the external power supply to the Arduino and everything is working as expected

Good thinking! :slight_smile:
Common Ground

Ground in most cases is a term that indicates the reference point!

try using common ground. For you to have a better result in sensor

sorry for bad english hahahaha