Diode to GND as polarity protection.

[alparent]

Thinking of using a diode to GND instead of a diode in series as polarity protection.
Any pros and cons (other then not loosing any voltage)?

[Gurner]

cons   ......You need to use a fuse in line with the supply line (before the diode)  ...else reverse polarity = mucho current through diode & diode goes pop (stinkage & heartache occurs)

[alparent]

Replaying to your own post! Nice  

Reading RG's "Advanced Power Switching and Polarity Protection for Effects" talks about it.

Thanks RG.  

[EATyourGuitar]

this is done in some synthesizer modules and it works great. the only problem is reduced power supply voltage and therefor reduced headroom. you might want to put that diode on your V+ instead of your GND since all your unbalanced audio references ground directly without the diode. it probably wont make a difference what side it is on however as long as your circuit is continuously passing enough current through the diode to keep it on all the time. I have been searching for diodes with smaller current requirements and smaller forward voltage lately. besides the obvious but expensive germanium, I found BAT41 BAT42 BAT43 BAT81 BAT81S BAT82 BAT83. in SMT there are tons of switching diodes with very low Vf at 1mA.

[alparent]

Remembered another thread about this and with a little research I found it again.