Can road rage provide +12, -12v?

[luckylulujoe13]

Hello there. I am trying to build a pitch to voltage convertor from a board designed by Harry Bissel. It calls for +12v and -12v for power. Can I modify the road rage to provide these voltages? Thanks.

[midwayfair]

Not by itself.

There are two ways to get there using the RR as a base:
1. Get a 12V regulator and a negative 12V regulator. Double the voltage as normal. Use 4001s for the diodes instead of 5817s, which will make the final double voltage closer to 16V and punish the regulator less. Hook up the voltage regulator as normal on the Road Rage.

Use a daughter board to convert the negative output (pin 5) to a doubled negative voltage. The datasheet has the schematic for this. You should be able to build it easily on a little piece of perfboard. Now hook up the negative voltage regulator and take your negative voltage output from the regulator.

You now have +12V/-12V from a 9V supply.

2. If you're using a regulated power supply -- or even just a One-Spot or anything else that puts out a consistent voltage -- use a few diodes to knock the input voltage down to about 7V. A single green LED might even do it. You can't really use a 6V regulator with a heat sink because your final voltage would be closer to 11V than 12V.

Use a daughter board to convert the negative output (pin 5) to a doubled negative voltage. The datasheet has the schematic for this. You should be able to build it easily on a little piece of perfboard.

You might need to change a diode or two somewhere in the chain to get to exactly 12V, but this method is slightly cheaper (fewer parts) and doesn't require a (harder to find) negative voltage regulator. Also, if you don't need exactly +12V/-12V regulated, it'll be just fine. This is what I'd do if I were building something for myself and knew exactly what I'd be plugging it into for power all the time.

[RobA]

If it's the circuit I found by doing a search just now, you should check the current draw for the board. The charge pumps can't source a lot of current and you'd have quite a bit going on there and on two rails.