3.3V Dallas one-wire bus on a 5V system

BillO:
... Even if you use a MOSFET without the internal diode...

I thought the diode is a "feature" of MOSFETs - it is integral (often unwanted) part of the MOSFET and you cannot make one without it. AFAIK when you need a MOSFET that is able to block current in both directions you need to use two MOSFETs.

wvmarle:
The MOSFET a small signal one like the BSS138.

It is difficult to get a THT MOSFET with low enough threshold voltage for this to work. However any NPN transistor can be used instead (with additional Base resistor ofc).