Hi experts :-)
This circuit above seems to short out the +3V3 rail when I push SW4. I suspect it is applying +3V3 to the base of Q10, which gives Vbe of 3V3, probably not desirable! My best guess is that this causes breakdown of the base emitter junction of Q10 effectively shorting out the 3V3 rail. If I put a 10k directly onto the base of Q10 would this sort out the issue or introduce more? Also would that still allow the microcontroller signal OPEN_2 to still switch on Q10 and therefore provide +V_BATT through Q7 and out to OPEN_2_12 ?
Also, its the Electronics Evening on Thursday if anyone wants to come along and tell me where I have gone wrong :-)