LM317 & LM337 Voltage Reg Testing

Hi,

Just a quick post showing the stability and accuracy of 2 separate voltage regulators working together. The mixer project requires a regulated positive and negative rail for the op-amps so I wanted to test how well they regulated when working together.

For this I used LM317 and LM337 adjustable positive and negative voltage regulators. The basic schematic I drew up is shown below.



Below are some tests showing the voltage drift over the course of an hour or so. As it was a quick test I had to work with the resistors I had on hand so don't pay much attention to the actual voltage but shown is the total of the negative 3 volt rail and positive 3 volt rail. Obviously in the final circuit the total will be 6 volts and not the 5.3 shown.



I'll go into more detail in another post I just thought I'd share the results from this quick test.

Justin

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