LM2596-ADJ Inverting Regulator

ee tech

Prodigy 220 points

I haven't been able to find info on a schematic for an LM2596-ADJ inverting adjustable regulator.

There is one on the datasheet for the fixed version but not the adjustable version.

I tried using WEBENCH but it wont allow a negative output value if the input value is positive.

1. Does anyone have a schematic to share?

2. Is the equation for calculating the programming resistors for negative output the same as the fixed regulators?

thanks

over 9 years ago

0 Frank De Stasi over 9 years ago

TI__Guru 64365 points

I have attached a crude schematic. Vout=Vref*((RA/RB)

+ 1)

Same equation as an ordinary regulator; use absolute values.

0 Jeff Lampe over 9 years ago in reply to Frank De Stasi

Intellectual 530 points

try checking these out for references

https://www.google.com/search?q=lm2596-adj+circuit&safe=off&espv=2&tbm=isch&tbo=u&source=univ&sa=X&ei=fAu3VJD_HMXegwS-7oOYDw&ved=0CD4QsAQ&biw=1024&bih=643

0 Jeff Lampe over 9 years ago in reply to Frank De Stasi

Intellectual 530 points

start with Figure 37 Schematic and modify the feedback to the Adjustable Output Voltage Versions,, I would use a potentiometer for R2

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LM2596-ADJ Inverting Regulator