Need a negative voltage from a 0-60V power supply

AI Thread Summary
To create a negative voltage from a 0-60V power supply for an op-amp circuit, it's suggested to set the supply to 18V and establish a ground reference for a split supply. The unconventional wiring of the op-amp power supply pins should be corrected, with the top pin receiving +9V and the bottom pin -9V. Using a resistor divider to create a -5V supply is possible but not ideal; a more effective solution is to implement an inverting voltage regulator. This approach simplifies the design and addresses bias issues effectively. Proper decoupling with capacitors is also recommended for stability.
atlbraves49
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I will have to power the following circuit:

http://www.tekscan.com/images/flexi-circuit-new.jpg

I assume I can just hook the (-) terminal to the -9V input, the (+) terminal to the +9V input, set the power supply to 9V, and then toss a resistor between the -9V and the -5V?

Would that work? And what value resistor would i need between the -9V and -5V?
 
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First, on your figure, you should show the top opamp power supply pin as +9V and the bottom supply pin as -9V. The way you have them now is unconventional.

Second, I think you mean to say that you will set your 0-60V single power supply to 18V, and you want to know the best way to make a middle rail be ground, as well as make a -5V supply. This is discussed a bit in your other thread, I believe. Turning a single supply into split supplies is not a great option, but can be done if the impedances and powers involved lend themselves to a resistor divider with adequate capacitor decoupling.
 
Since your only powering an op amp, just use an inverting voltage regulator. I actually just finished hooking one up to an instrumentation amp a couple hours ago.
 
altbraves, a two opamp, single supply design would get around this bias issue.
 
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