A microcontroller GPIO is connected to RP_SW and 5v_Raspberry is the power supply of the Raspberry. The Q9 FET and DT_1 transistors with R65 and R66 are making an ideal diode, I took the idea from here (The aim of this diode is to avoid back powering).
The problem is, that the 5V_Raspberry will be only ~2.3V, the rest of the voltage is falling on the drain-source of the Q8 FET. I tried to pull up the gate of the Q8 FET to 5V, but there is no change. I tried an other FET instead of Q8, but the same effect is shown. Why is this circiut not working, as excepted?