PowerSupply. - Here is Circuit Schematic 0.5 Volt Negative Supply 4 Power Supply. A while back someone needed a simple way to generate a negative 0.5v supply from a conventional transformer type AC to DC power supply. The circuit below uses a couple schottky diodes and a filter capacitor to perform the feat. The circuit is handy when using “rail to rail” op amp circuits which get close to zero volts at their output from a single DC supply but can’t quite deliver without a negative supply. With the aid of the 0.5v supply circuit shown, those devices can produce a true zero output voltage.
The Original Article : "0.5v Negative Supply 4"