The Pi has internal weak pull up (and down) ‘virtual resistors’ and it seems that a short script / mod could be made to make the DS18B20 digital temperature probes Direct Connect’ to the Pi GPIO header with No interfacing circuit (4k7 pull up resistor) People might like to try this for a simple no fuss approach, esp using the 1m / 3m leaded industrial DS18B20 probes you can now get:
I soldered the three (+ve 3.3 -ve and 1w wires direct to a handy 5 way SIL socket
A few lines of code will activate the WPU resgister, in this case set it and exit leaving the WPU active until restart / reboot.
Save this as a program.py which can also auto execute using cron at boot up.
import RPi.GPIO as GPIO
GPIO.setmode(GPIO.BCM) # set up BCM GPIO numbering
GPIO.setup(4, GPIO.IN, pull_up_down=GPIO.PUD_UP)
I have tested this with multiple DS18B20 and works fine.